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      1 /*
      2  * Copyright (C) 2006 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.webkit;
     18 
     19 import android.annotation.IntDef;
     20 import android.annotation.NonNull;
     21 import android.annotation.Nullable;
     22 import android.annotation.SystemApi;
     23 import android.annotation.Widget;
     24 import android.content.Context;
     25 import android.content.Intent;
     26 import android.content.pm.PackageInfo;
     27 import android.content.res.Configuration;
     28 import android.graphics.Bitmap;
     29 import android.graphics.Canvas;
     30 import android.graphics.Paint;
     31 import android.graphics.Picture;
     32 import android.graphics.Rect;
     33 import android.graphics.drawable.Drawable;
     34 import android.net.Uri;
     35 import android.net.http.SslCertificate;
     36 import android.os.Build;
     37 import android.os.Bundle;
     38 import android.os.Handler;
     39 import android.os.Looper;
     40 import android.os.Message;
     41 import android.os.RemoteException;
     42 import android.os.StrictMode;
     43 import android.print.PrintDocumentAdapter;
     44 import android.security.KeyChain;
     45 import android.util.AttributeSet;
     46 import android.util.Log;
     47 import android.util.SparseArray;
     48 import android.view.DragEvent;
     49 import android.view.KeyEvent;
     50 import android.view.MotionEvent;
     51 import android.view.View;
     52 import android.view.ViewDebug;
     53 import android.view.ViewGroup;
     54 import android.view.ViewHierarchyEncoder;
     55 import android.view.ViewStructure;
     56 import android.view.ViewTreeObserver;
     57 import android.view.accessibility.AccessibilityEvent;
     58 import android.view.accessibility.AccessibilityNodeInfo;
     59 import android.view.accessibility.AccessibilityNodeProvider;
     60 import android.view.autofill.AutofillValue;
     61 import android.view.inputmethod.EditorInfo;
     62 import android.view.inputmethod.InputConnection;
     63 import android.view.textclassifier.TextClassifier;
     64 import android.widget.AbsoluteLayout;
     65 
     66 import java.io.BufferedWriter;
     67 import java.io.File;
     68 import java.lang.annotation.Retention;
     69 import java.lang.annotation.RetentionPolicy;
     70 import java.util.List;
     71 import java.util.Map;
     72 
     73 /**
     74  * <p>A View that displays web pages. This class is the basis upon which you
     75  * can roll your own web browser or simply display some online content within your Activity.
     76  * It uses the WebKit rendering engine to display
     77  * web pages and includes methods to navigate forward and backward
     78  * through a history, zoom in and out, perform text searches and more.</p>
     79  * <p>Note that, in order for your Activity to access the Internet and load web pages
     80  * in a WebView, you must add the {@code INTERNET} permissions to your
     81  * Android Manifest file:</p>
     82  * <pre>&lt;uses-permission android:name="android.permission.INTERNET" /></pre>
     83  *
     84  * <p>This must be a child of the <a
     85  * href="{@docRoot}guide/topics/manifest/manifest-element.html">{@code <manifest>}</a>
     86  * element.</p>
     87  *
     88  * <p>For more information, read
     89  * <a href="{@docRoot}guide/webapps/webview.html">Building Web Apps in WebView</a>.</p>
     90  *
     91  * <h3>Basic usage</h3>
     92  *
     93  * <p>By default, a WebView provides no browser-like widgets, does not
     94  * enable JavaScript and web page errors are ignored. If your goal is only
     95  * to display some HTML as a part of your UI, this is probably fine;
     96  * the user won't need to interact with the web page beyond reading
     97  * it, and the web page won't need to interact with the user. If you
     98  * actually want a full-blown web browser, then you probably want to
     99  * invoke the Browser application with a URL Intent rather than show it
    100  * with a WebView. For example:
    101  * <pre>
    102  * Uri uri = Uri.parse("https://www.example.com");
    103  * Intent intent = new Intent(Intent.ACTION_VIEW, uri);
    104  * startActivity(intent);
    105  * </pre>
    106  * <p>See {@link android.content.Intent} for more information.</p>
    107  *
    108  * <p>To provide a WebView in your own Activity, include a {@code <WebView>} in your layout,
    109  * or set the entire Activity window as a WebView during {@link
    110  * android.app.Activity#onCreate(Bundle) onCreate()}:</p>
    111  * <pre class="prettyprint">
    112  * WebView webview = new WebView(this);
    113  * setContentView(webview);
    114  * </pre>
    115  *
    116  * <p>Then load the desired web page:</p>
    117  * <pre>
    118  * // Simplest usage: note that an exception will NOT be thrown
    119  * // if there is an error loading this page (see below).
    120  * webview.loadUrl("https://example.com/");
    121  *
    122  * // OR, you can also load from an HTML string:
    123  * String summary = "&lt;html>&lt;body>You scored &lt;b>192&lt;/b> points.&lt;/body>&lt;/html>";
    124  * webview.loadData(summary, "text/html", null);
    125  * // ... although note that there are restrictions on what this HTML can do.
    126  * // See the JavaDocs for {@link #loadData(String,String,String) loadData()} and {@link
    127  * #loadDataWithBaseURL(String,String,String,String,String) loadDataWithBaseURL()} for more info.
    128  * </pre>
    129  *
    130  * <p>A WebView has several customization points where you can add your
    131  * own behavior. These are:</p>
    132  *
    133  * <ul>
    134  *   <li>Creating and setting a {@link android.webkit.WebChromeClient} subclass.
    135  *       This class is called when something that might impact a
    136  *       browser UI happens, for instance, progress updates and
    137  *       JavaScript alerts are sent here (see <a
    138  * href="{@docRoot}guide/developing/debug-tasks.html#DebuggingWebPages">Debugging Tasks</a>).
    139  *   </li>
    140  *   <li>Creating and setting a {@link android.webkit.WebViewClient} subclass.
    141  *       It will be called when things happen that impact the
    142  *       rendering of the content, eg, errors or form submissions. You
    143  *       can also intercept URL loading here (via {@link
    144  * android.webkit.WebViewClient#shouldOverrideUrlLoading(WebView,String)
    145  * shouldOverrideUrlLoading()}).</li>
    146  *   <li>Modifying the {@link android.webkit.WebSettings}, such as
    147  * enabling JavaScript with {@link android.webkit.WebSettings#setJavaScriptEnabled(boolean)
    148  * setJavaScriptEnabled()}. </li>
    149  *   <li>Injecting Java objects into the WebView using the
    150  *       {@link android.webkit.WebView#addJavascriptInterface} method. This
    151  *       method allows you to inject Java objects into a page's JavaScript
    152  *       context, so that they can be accessed by JavaScript in the page.</li>
    153  * </ul>
    154  *
    155  * <p>Here's a more complicated example, showing error handling,
    156  *    settings, and progress notification:</p>
    157  *
    158  * <pre class="prettyprint">
    159  * // Let's display the progress in the activity title bar, like the
    160  * // browser app does.
    161  * getWindow().requestFeature(Window.FEATURE_PROGRESS);
    162  *
    163  * webview.getSettings().setJavaScriptEnabled(true);
    164  *
    165  * final Activity activity = this;
    166  * webview.setWebChromeClient(new WebChromeClient() {
    167  *   public void onProgressChanged(WebView view, int progress) {
    168  *     // Activities and WebViews measure progress with different scales.
    169  *     // The progress meter will automatically disappear when we reach 100%
    170  *     activity.setProgress(progress * 1000);
    171  *   }
    172  * });
    173  * webview.setWebViewClient(new WebViewClient() {
    174  *   public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
    175  *     Toast.makeText(activity, "Oh no! " + description, Toast.LENGTH_SHORT).show();
    176  *   }
    177  * });
    178  *
    179  * webview.loadUrl("https://developer.android.com/");
    180  * </pre>
    181  *
    182  * <h3>Zoom</h3>
    183  *
    184  * <p>To enable the built-in zoom, set
    185  * {@link #getSettings() WebSettings}.{@link WebSettings#setBuiltInZoomControls(boolean)}
    186  * (introduced in API level {@link android.os.Build.VERSION_CODES#CUPCAKE}).</p>
    187  * <p>NOTE: Using zoom if either the height or width is set to
    188  * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} may lead to undefined behavior
    189  * and should be avoided.</p>
    190  *
    191  * <h3>Cookie and window management</h3>
    192  *
    193  * <p>For obvious security reasons, your application has its own
    194  * cache, cookie store etc.&mdash;it does not share the Browser
    195  * application's data.
    196  * </p>
    197  *
    198  * <p>By default, requests by the HTML to open new windows are
    199  * ignored. This is true whether they be opened by JavaScript or by
    200  * the target attribute on a link. You can customize your
    201  * {@link WebChromeClient} to provide your own behavior for opening multiple windows,
    202  * and render them in whatever manner you want.</p>
    203  *
    204  * <p>The standard behavior for an Activity is to be destroyed and
    205  * recreated when the device orientation or any other configuration changes. This will cause
    206  * the WebView to reload the current page. If you don't want that, you
    207  * can set your Activity to handle the {@code orientation} and {@code keyboardHidden}
    208  * changes, and then just leave the WebView alone. It'll automatically
    209  * re-orient itself as appropriate. Read <a
    210  * href="{@docRoot}guide/topics/resources/runtime-changes.html">Handling Runtime Changes</a> for
    211  * more information about how to handle configuration changes during runtime.</p>
    212  *
    213  *
    214  * <h3>Building web pages to support different screen densities</h3>
    215  *
    216  * <p>The screen density of a device is based on the screen resolution. A screen with low density
    217  * has fewer available pixels per inch, where a screen with high density
    218  * has more &mdash; sometimes significantly more &mdash; pixels per inch. The density of a
    219  * screen is important because, other things being equal, a UI element (such as a button) whose
    220  * height and width are defined in terms of screen pixels will appear larger on the lower density
    221  * screen and smaller on the higher density screen.
    222  * For simplicity, Android collapses all actual screen densities into three generalized densities:
    223  * high, medium, and low.</p>
    224  * <p>By default, WebView scales a web page so that it is drawn at a size that matches the default
    225  * appearance on a medium density screen. So, it applies 1.5x scaling on a high density screen
    226  * (because its pixels are smaller) and 0.75x scaling on a low density screen (because its pixels
    227  * are bigger).
    228  * Starting with API level {@link android.os.Build.VERSION_CODES#ECLAIR}, WebView supports DOM, CSS,
    229  * and meta tag features to help you (as a web developer) target screens with different screen
    230  * densities.</p>
    231  * <p>Here's a summary of the features you can use to handle different screen densities:</p>
    232  * <ul>
    233  * <li>The {@code window.devicePixelRatio} DOM property. The value of this property specifies the
    234  * default scaling factor used for the current device. For example, if the value of {@code
    235  * window.devicePixelRatio} is "1.0", then the device is considered a medium density (mdpi) device
    236  * and default scaling is not applied to the web page; if the value is "1.5", then the device is
    237  * considered a high density device (hdpi) and the page content is scaled 1.5x; if the
    238  * value is "0.75", then the device is considered a low density device (ldpi) and the content is
    239  * scaled 0.75x.</li>
    240  * <li>The {@code -webkit-device-pixel-ratio} CSS media query. Use this to specify the screen
    241  * densities for which this style sheet is to be used. The corresponding value should be either
    242  * "0.75", "1", or "1.5", to indicate that the styles are for devices with low density, medium
    243  * density, or high density screens, respectively. For example:
    244  * <pre>
    245  * &lt;link rel="stylesheet" media="screen and (-webkit-device-pixel-ratio:1.5)" href="hdpi.css" /&gt;</pre>
    246  * <p>The {@code hdpi.css} stylesheet is only used for devices with a screen pixel ration of 1.5,
    247  * which is the high density pixel ratio.</p>
    248  * </li>
    249  * </ul>
    250  *
    251  * <h3>HTML5 Video support</h3>
    252  *
    253  * <p>In order to support inline HTML5 video in your application you need to have hardware
    254  * acceleration turned on.
    255  * </p>
    256  *
    257  * <h3>Full screen support</h3>
    258  *
    259  * <p>In order to support full screen &mdash; for video or other HTML content &mdash; you need to set a
    260  * {@link android.webkit.WebChromeClient} and implement both
    261  * {@link WebChromeClient#onShowCustomView(View, WebChromeClient.CustomViewCallback)}
    262  * and {@link WebChromeClient#onHideCustomView()}. If the implementation of either of these two methods is
    263  * missing then the web contents will not be allowed to enter full screen. Optionally you can implement
    264  * {@link WebChromeClient#getVideoLoadingProgressView()} to customize the View displayed whilst a video
    265  * is loading.
    266  * </p>
    267  *
    268  * <h3>HTML5 Geolocation API support</h3>
    269  *
    270  * <p>For applications targeting Android N and later releases
    271  * (API level > {@link android.os.Build.VERSION_CODES#M}) the geolocation api is only supported on
    272  * secure origins such as https. For such applications requests to geolocation api on non-secure
    273  * origins are automatically denied without invoking the corresponding
    274  * {@link WebChromeClient#onGeolocationPermissionsShowPrompt(String, GeolocationPermissions.Callback)}
    275  * method.
    276  * </p>
    277  *
    278  * <h3>Layout size</h3>
    279  * <p>
    280  * It is recommended to set the WebView layout height to a fixed value or to
    281  * {@link android.view.ViewGroup.LayoutParams#MATCH_PARENT} instead of using
    282  * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT}.
    283  * When using {@link android.view.ViewGroup.LayoutParams#MATCH_PARENT}
    284  * for the height none of the WebView's parents should use a
    285  * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} layout height since that could result in
    286  * incorrect sizing of the views.
    287  * </p>
    288  *
    289  * <p>Setting the WebView's height to {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT}
    290  * enables the following behaviors:
    291  * <ul>
    292  * <li>The HTML body layout height is set to a fixed value. This means that elements with a height
    293  * relative to the HTML body may not be sized correctly. </li>
    294  * <li>For applications targeting {@link android.os.Build.VERSION_CODES#KITKAT} and earlier SDKs the
    295  * HTML viewport meta tag will be ignored in order to preserve backwards compatibility. </li>
    296  * </ul>
    297  * </p>
    298  *
    299  * <p>
    300  * Using a layout width of {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} is not
    301  * supported. If such a width is used the WebView will attempt to use the width of the parent
    302  * instead.
    303  * </p>
    304  *
    305  * <h3>Metrics</h3>
    306  *
    307  * <p>
    308  * WebView may upload anonymous diagnostic data to Google when the user has consented. This data
    309  * helps Google improve WebView. Data is collected on a per-app basis for each app which has
    310  * instantiated a WebView. An individual app can opt out of this feature by putting the following
    311  * tag in its manifest:
    312  * <pre>
    313  * &lt;meta-data android:name="android.webkit.WebView.MetricsOptOut"
    314  *            android:value="true" /&gt;
    315  * </pre>
    316  * </p>
    317  * <p>
    318  * Data will only be uploaded for a given app if the user has consented AND the app has not opted
    319  * out.
    320  * </p>
    321  *
    322  * <h3>Safe Browsing</h3>
    323  *
    324  * <p>
    325  * If Safe Browsing is enabled, WebView will block malicious URLs and present a warning UI to the
    326  * user to allow them to navigate back safely or proceed to the malicious page.
    327  * </p>
    328  * <p>
    329  * The recommended way for apps to enable the feature is putting the following tag in the manifest:
    330  * </p>
    331  * <p>
    332  * <pre>
    333  * &lt;meta-data android:name="android.webkit.WebView.EnableSafeBrowsing"
    334  *            android:value="true" /&gt;
    335  * </pre>
    336  * </p>
    337  *
    338  */
    339 // Implementation notes.
    340 // The WebView is a thin API class that delegates its public API to a backend WebViewProvider
    341 // class instance. WebView extends {@link AbsoluteLayout} for backward compatibility reasons.
    342 // Methods are delegated to the provider implementation: all public API methods introduced in this
    343 // file are fully delegated, whereas public and protected methods from the View base classes are
    344 // only delegated where a specific need exists for them to do so.
    345 @Widget
    346 public class WebView extends AbsoluteLayout
    347         implements ViewTreeObserver.OnGlobalFocusChangeListener,
    348         ViewGroup.OnHierarchyChangeListener, ViewDebug.HierarchyHandler {
    349 
    350     private static final String LOGTAG = "WebView";
    351 
    352     // Throwing an exception for incorrect thread usage if the
    353     // build target is JB MR2 or newer. Defaults to false, and is
    354     // set in the WebView constructor.
    355     private static volatile boolean sEnforceThreadChecking = false;
    356 
    357     /**
    358      *  Transportation object for returning WebView across thread boundaries.
    359      */
    360     public class WebViewTransport {
    361         private WebView mWebview;
    362 
    363         /**
    364          * Sets the WebView to the transportation object.
    365          *
    366          * @param webview the WebView to transport
    367          */
    368         public synchronized void setWebView(WebView webview) {
    369             mWebview = webview;
    370         }
    371 
    372         /**
    373          * Gets the WebView object.
    374          *
    375          * @return the transported WebView object
    376          */
    377         public synchronized WebView getWebView() {
    378             return mWebview;
    379         }
    380     }
    381 
    382     /**
    383      * URI scheme for telephone number.
    384      */
    385     public static final String SCHEME_TEL = "tel:";
    386     /**
    387      * URI scheme for email address.
    388      */
    389     public static final String SCHEME_MAILTO = "mailto:";
    390     /**
    391      * URI scheme for map address.
    392      */
    393     public static final String SCHEME_GEO = "geo:0,0?q=";
    394 
    395     /**
    396      * Interface to listen for find results.
    397      */
    398     public interface FindListener {
    399         /**
    400          * Notifies the listener about progress made by a find operation.
    401          *
    402          * @param activeMatchOrdinal the zero-based ordinal of the currently selected match
    403          * @param numberOfMatches how many matches have been found
    404          * @param isDoneCounting whether the find operation has actually completed. The listener
    405          *                       may be notified multiple times while the
    406          *                       operation is underway, and the numberOfMatches
    407          *                       value should not be considered final unless
    408          *                       isDoneCounting is true.
    409          */
    410         public void onFindResultReceived(int activeMatchOrdinal, int numberOfMatches,
    411             boolean isDoneCounting);
    412     }
    413 
    414     /**
    415      * Callback interface supplied to {@link #postVisualStateCallback} for receiving
    416      * notifications about the visual state.
    417      */
    418     public static abstract class VisualStateCallback {
    419         /**
    420          * Invoked when the visual state is ready to be drawn in the next {@link #onDraw}.
    421          *
    422          * @param requestId The identifier passed to {@link #postVisualStateCallback} when this
    423          *                  callback was posted.
    424          */
    425         public abstract void onComplete(long requestId);
    426     }
    427 
    428     /**
    429      * Interface to listen for new pictures as they change.
    430      *
    431      * @deprecated This interface is now obsolete.
    432      */
    433     @Deprecated
    434     public interface PictureListener {
    435         /**
    436          * Used to provide notification that the WebView's picture has changed.
    437          * See {@link WebView#capturePicture} for details of the picture.
    438          *
    439          * @param view the WebView that owns the picture
    440          * @param picture the new picture. Applications targeting
    441          *     {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2} or above
    442          *     will always receive a null Picture.
    443          * @deprecated Deprecated due to internal changes.
    444          */
    445         @Deprecated
    446         public void onNewPicture(WebView view, Picture picture);
    447     }
    448 
    449     public static class HitTestResult {
    450         /**
    451          * Default HitTestResult, where the target is unknown.
    452          */
    453         public static final int UNKNOWN_TYPE = 0;
    454         /**
    455          * @deprecated This type is no longer used.
    456          */
    457         @Deprecated
    458         public static final int ANCHOR_TYPE = 1;
    459         /**
    460          * HitTestResult for hitting a phone number.
    461          */
    462         public static final int PHONE_TYPE = 2;
    463         /**
    464          * HitTestResult for hitting a map address.
    465          */
    466         public static final int GEO_TYPE = 3;
    467         /**
    468          * HitTestResult for hitting an email address.
    469          */
    470         public static final int EMAIL_TYPE = 4;
    471         /**
    472          * HitTestResult for hitting an HTML::img tag.
    473          */
    474         public static final int IMAGE_TYPE = 5;
    475         /**
    476          * @deprecated This type is no longer used.
    477          */
    478         @Deprecated
    479         public static final int IMAGE_ANCHOR_TYPE = 6;
    480         /**
    481          * HitTestResult for hitting a HTML::a tag with src=http.
    482          */
    483         public static final int SRC_ANCHOR_TYPE = 7;
    484         /**
    485          * HitTestResult for hitting a HTML::a tag with src=http + HTML::img.
    486          */
    487         public static final int SRC_IMAGE_ANCHOR_TYPE = 8;
    488         /**
    489          * HitTestResult for hitting an edit text area.
    490          */
    491         public static final int EDIT_TEXT_TYPE = 9;
    492 
    493         private int mType;
    494         private String mExtra;
    495 
    496         /**
    497          * @hide Only for use by WebViewProvider implementations
    498          */
    499         @SystemApi
    500         public HitTestResult() {
    501             mType = UNKNOWN_TYPE;
    502         }
    503 
    504         /**
    505          * @hide Only for use by WebViewProvider implementations
    506          */
    507         @SystemApi
    508         public void setType(int type) {
    509             mType = type;
    510         }
    511 
    512         /**
    513          * @hide Only for use by WebViewProvider implementations
    514          */
    515         @SystemApi
    516         public void setExtra(String extra) {
    517             mExtra = extra;
    518         }
    519 
    520         /**
    521          * Gets the type of the hit test result. See the XXX_TYPE constants
    522          * defined in this class.
    523          *
    524          * @return the type of the hit test result
    525          */
    526         public int getType() {
    527             return mType;
    528         }
    529 
    530         /**
    531          * Gets additional type-dependant information about the result. See
    532          * {@link WebView#getHitTestResult()} for details. May either be null
    533          * or contain extra information about this result.
    534          *
    535          * @return additional type-dependant information about the result
    536          */
    537         public String getExtra() {
    538             return mExtra;
    539         }
    540     }
    541 
    542     /**
    543      * Constructs a new WebView with a Context object.
    544      *
    545      * @param context a Context object used to access application assets
    546      */
    547     public WebView(Context context) {
    548         this(context, null);
    549     }
    550 
    551     /**
    552      * Constructs a new WebView with layout parameters.
    553      *
    554      * @param context a Context object used to access application assets
    555      * @param attrs an AttributeSet passed to our parent
    556      */
    557     public WebView(Context context, AttributeSet attrs) {
    558         this(context, attrs, com.android.internal.R.attr.webViewStyle);
    559     }
    560 
    561     /**
    562      * Constructs a new WebView with layout parameters and a default style.
    563      *
    564      * @param context a Context object used to access application assets
    565      * @param attrs an AttributeSet passed to our parent
    566      * @param defStyleAttr an attribute in the current theme that contains a
    567      *        reference to a style resource that supplies default values for
    568      *        the view. Can be 0 to not look for defaults.
    569      */
    570     public WebView(Context context, AttributeSet attrs, int defStyleAttr) {
    571         this(context, attrs, defStyleAttr, 0);
    572     }
    573 
    574     /**
    575      * Constructs a new WebView with layout parameters and a default style.
    576      *
    577      * @param context a Context object used to access application assets
    578      * @param attrs an AttributeSet passed to our parent
    579      * @param defStyleAttr an attribute in the current theme that contains a
    580      *        reference to a style resource that supplies default values for
    581      *        the view. Can be 0 to not look for defaults.
    582      * @param defStyleRes a resource identifier of a style resource that
    583      *        supplies default values for the view, used only if
    584      *        defStyleAttr is 0 or can not be found in the theme. Can be 0
    585      *        to not look for defaults.
    586      */
    587     public WebView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
    588         this(context, attrs, defStyleAttr, defStyleRes, null, false);
    589     }
    590 
    591     /**
    592      * Constructs a new WebView with layout parameters and a default style.
    593      *
    594      * @param context a Context object used to access application assets
    595      * @param attrs an AttributeSet passed to our parent
    596      * @param defStyleAttr an attribute in the current theme that contains a
    597      *        reference to a style resource that supplies default values for
    598      *        the view. Can be 0 to not look for defaults.
    599      * @param privateBrowsing whether this WebView will be initialized in
    600      *                        private mode
    601      *
    602      * @deprecated Private browsing is no longer supported directly via
    603      * WebView and will be removed in a future release. Prefer using
    604      * {@link WebSettings}, {@link WebViewDatabase}, {@link CookieManager}
    605      * and {@link WebStorage} for fine-grained control of privacy data.
    606      */
    607     @Deprecated
    608     public WebView(Context context, AttributeSet attrs, int defStyleAttr,
    609             boolean privateBrowsing) {
    610         this(context, attrs, defStyleAttr, 0, null, privateBrowsing);
    611     }
    612 
    613     /**
    614      * Constructs a new WebView with layout parameters, a default style and a set
    615      * of custom JavaScript interfaces to be added to this WebView at initialization
    616      * time. This guarantees that these interfaces will be available when the JS
    617      * context is initialized.
    618      *
    619      * @param context a Context object used to access application assets
    620      * @param attrs an AttributeSet passed to our parent
    621      * @param defStyleAttr an attribute in the current theme that contains a
    622      *        reference to a style resource that supplies default values for
    623      *        the view. Can be 0 to not look for defaults.
    624      * @param javaScriptInterfaces a Map of interface names, as keys, and
    625      *                             object implementing those interfaces, as
    626      *                             values
    627      * @param privateBrowsing whether this WebView will be initialized in
    628      *                        private mode
    629      * @hide This is used internally by dumprendertree, as it requires the JavaScript interfaces to
    630      *       be added synchronously, before a subsequent loadUrl call takes effect.
    631      */
    632     protected WebView(Context context, AttributeSet attrs, int defStyleAttr,
    633             Map<String, Object> javaScriptInterfaces, boolean privateBrowsing) {
    634         this(context, attrs, defStyleAttr, 0, javaScriptInterfaces, privateBrowsing);
    635     }
    636 
    637     /**
    638      * @hide
    639      */
    640     @SuppressWarnings("deprecation")  // for super() call into deprecated base class constructor.
    641     protected WebView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes,
    642             Map<String, Object> javaScriptInterfaces, boolean privateBrowsing) {
    643         super(context, attrs, defStyleAttr, defStyleRes);
    644 
    645         // WebView is important by default, unless app developer overrode attribute.
    646         if (getImportantForAutofill() == IMPORTANT_FOR_AUTOFILL_AUTO) {
    647             setImportantForAutofill(IMPORTANT_FOR_AUTOFILL_YES);
    648         }
    649 
    650         if (context == null) {
    651             throw new IllegalArgumentException("Invalid context argument");
    652         }
    653         sEnforceThreadChecking = context.getApplicationInfo().targetSdkVersion >=
    654                 Build.VERSION_CODES.JELLY_BEAN_MR2;
    655         checkThread();
    656 
    657         ensureProviderCreated();
    658         mProvider.init(javaScriptInterfaces, privateBrowsing);
    659         // Post condition of creating a webview is the CookieSyncManager.getInstance() is allowed.
    660         CookieSyncManager.setGetInstanceIsAllowed();
    661     }
    662 
    663     /**
    664      * Specifies whether the horizontal scrollbar has overlay style.
    665      *
    666      * @deprecated This method has no effect.
    667      * @param overlay true if horizontal scrollbar should have overlay style
    668      */
    669     @Deprecated
    670     public void setHorizontalScrollbarOverlay(boolean overlay) {
    671     }
    672 
    673     /**
    674      * Specifies whether the vertical scrollbar has overlay style.
    675      *
    676      * @deprecated This method has no effect.
    677      * @param overlay true if vertical scrollbar should have overlay style
    678      */
    679     @Deprecated
    680     public void setVerticalScrollbarOverlay(boolean overlay) {
    681     }
    682 
    683     /**
    684      * Gets whether horizontal scrollbar has overlay style.
    685      *
    686      * @deprecated This method is now obsolete.
    687      * @return true
    688      */
    689     @Deprecated
    690     public boolean overlayHorizontalScrollbar() {
    691         // The old implementation defaulted to true, so return true for consistency
    692         return true;
    693     }
    694 
    695     /**
    696      * Gets whether vertical scrollbar has overlay style.
    697      *
    698      * @deprecated This method is now obsolete.
    699      * @return false
    700      */
    701     @Deprecated
    702     public boolean overlayVerticalScrollbar() {
    703         // The old implementation defaulted to false, so return false for consistency
    704         return false;
    705     }
    706 
    707     /**
    708      * Gets the visible height (in pixels) of the embedded title bar (if any).
    709      *
    710      * @deprecated This method is now obsolete.
    711      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
    712      */
    713     @Deprecated
    714     public int getVisibleTitleHeight() {
    715         checkThread();
    716         return mProvider.getVisibleTitleHeight();
    717     }
    718 
    719     /**
    720      * Gets the SSL certificate for the main top-level page or null if there is
    721      * no certificate (the site is not secure).
    722      *
    723      * @return the SSL certificate for the main top-level page
    724      */
    725     public SslCertificate getCertificate() {
    726         checkThread();
    727         return mProvider.getCertificate();
    728     }
    729 
    730     /**
    731      * Sets the SSL certificate for the main top-level page.
    732      *
    733      * @deprecated Calling this function has no useful effect, and will be
    734      * ignored in future releases.
    735      */
    736     @Deprecated
    737     public void setCertificate(SslCertificate certificate) {
    738         checkThread();
    739         mProvider.setCertificate(certificate);
    740     }
    741 
    742     //-------------------------------------------------------------------------
    743     // Methods called by activity
    744     //-------------------------------------------------------------------------
    745 
    746     /**
    747      * Sets a username and password pair for the specified host. This data is
    748      * used by the WebView to autocomplete username and password fields in web
    749      * forms. Note that this is unrelated to the credentials used for HTTP
    750      * authentication.
    751      *
    752      * @param host the host that required the credentials
    753      * @param username the username for the given host
    754      * @param password the password for the given host
    755      * @see WebViewDatabase#clearUsernamePassword
    756      * @see WebViewDatabase#hasUsernamePassword
    757      * @deprecated Saving passwords in WebView will not be supported in future versions.
    758      */
    759     @Deprecated
    760     public void savePassword(String host, String username, String password) {
    761         checkThread();
    762         mProvider.savePassword(host, username, password);
    763     }
    764 
    765     /**
    766      * Stores HTTP authentication credentials for a given host and realm to the {@link WebViewDatabase}
    767      * instance.
    768      *
    769      * @param host the host to which the credentials apply
    770      * @param realm the realm to which the credentials apply
    771      * @param username the username
    772      * @param password the password
    773      * @deprecated Use {@link WebViewDatabase#setHttpAuthUsernamePassword} instead
    774      */
    775     @Deprecated
    776     public void setHttpAuthUsernamePassword(String host, String realm,
    777             String username, String password) {
    778         checkThread();
    779         mProvider.setHttpAuthUsernamePassword(host, realm, username, password);
    780     }
    781 
    782     /**
    783      * Retrieves HTTP authentication credentials for a given host and realm from the {@link
    784      * WebViewDatabase} instance.
    785      * @param host the host to which the credentials apply
    786      * @param realm the realm to which the credentials apply
    787      * @return the credentials as a String array, if found. The first element
    788      *         is the username and the second element is the password. Null if
    789      *         no credentials are found.
    790      * @deprecated Use {@link WebViewDatabase#getHttpAuthUsernamePassword} instead
    791      */
    792     @Deprecated
    793     public String[] getHttpAuthUsernamePassword(String host, String realm) {
    794         checkThread();
    795         return mProvider.getHttpAuthUsernamePassword(host, realm);
    796     }
    797 
    798     /**
    799      * Destroys the internal state of this WebView. This method should be called
    800      * after this WebView has been removed from the view system. No other
    801      * methods may be called on this WebView after destroy.
    802      */
    803     public void destroy() {
    804         checkThread();
    805         mProvider.destroy();
    806     }
    807 
    808     /**
    809      * Enables platform notifications of data state and proxy changes.
    810      * Notifications are enabled by default.
    811      *
    812      * @deprecated This method is now obsolete.
    813      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
    814      */
    815     @Deprecated
    816     public static void enablePlatformNotifications() {
    817         // noop
    818     }
    819 
    820     /**
    821      * Disables platform notifications of data state and proxy changes.
    822      * Notifications are enabled by default.
    823      *
    824      * @deprecated This method is now obsolete.
    825      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
    826      */
    827     @Deprecated
    828     public static void disablePlatformNotifications() {
    829         // noop
    830     }
    831 
    832     /**
    833      * Used only by internal tests to free up memory.
    834      *
    835      * @hide
    836      */
    837     public static void freeMemoryForTests() {
    838         getFactory().getStatics().freeMemoryForTests();
    839     }
    840 
    841     /**
    842      * Informs WebView of the network state. This is used to set
    843      * the JavaScript property window.navigator.isOnline and
    844      * generates the online/offline event as specified in HTML5, sec. 5.7.7
    845      *
    846      * @param networkUp a boolean indicating if network is available
    847      */
    848     public void setNetworkAvailable(boolean networkUp) {
    849         checkThread();
    850         mProvider.setNetworkAvailable(networkUp);
    851     }
    852 
    853     /**
    854      * Saves the state of this WebView used in
    855      * {@link android.app.Activity#onSaveInstanceState}. Please note that this
    856      * method no longer stores the display data for this WebView. The previous
    857      * behavior could potentially leak files if {@link #restoreState} was never
    858      * called.
    859      *
    860      * @param outState the Bundle to store this WebView's state
    861      * @return the same copy of the back/forward list used to save the state. If
    862      *         saveState fails, the returned list will be null.
    863      */
    864     public WebBackForwardList saveState(Bundle outState) {
    865         checkThread();
    866         return mProvider.saveState(outState);
    867     }
    868 
    869     /**
    870      * Saves the current display data to the Bundle given. Used in conjunction
    871      * with {@link #saveState}.
    872      * @param b a Bundle to store the display data
    873      * @param dest the file to store the serialized picture data. Will be
    874      *             overwritten with this WebView's picture data.
    875      * @return true if the picture was successfully saved
    876      * @deprecated This method is now obsolete.
    877      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
    878      */
    879     @Deprecated
    880     public boolean savePicture(Bundle b, final File dest) {
    881         checkThread();
    882         return mProvider.savePicture(b, dest);
    883     }
    884 
    885     /**
    886      * Restores the display data that was saved in {@link #savePicture}. Used in
    887      * conjunction with {@link #restoreState}. Note that this will not work if
    888      * this WebView is hardware accelerated.
    889      *
    890      * @param b a Bundle containing the saved display data
    891      * @param src the file where the picture data was stored
    892      * @return true if the picture was successfully restored
    893      * @deprecated This method is now obsolete.
    894      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
    895      */
    896     @Deprecated
    897     public boolean restorePicture(Bundle b, File src) {
    898         checkThread();
    899         return mProvider.restorePicture(b, src);
    900     }
    901 
    902     /**
    903      * Restores the state of this WebView from the given Bundle. This method is
    904      * intended for use in {@link android.app.Activity#onRestoreInstanceState}
    905      * and should be called to restore the state of this WebView. If
    906      * it is called after this WebView has had a chance to build state (load
    907      * pages, create a back/forward list, etc.) there may be undesirable
    908      * side-effects. Please note that this method no longer restores the
    909      * display data for this WebView.
    910      *
    911      * @param inState the incoming Bundle of state
    912      * @return the restored back/forward list or null if restoreState failed
    913      */
    914     public WebBackForwardList restoreState(Bundle inState) {
    915         checkThread();
    916         return mProvider.restoreState(inState);
    917     }
    918 
    919     /**
    920      * Loads the given URL with the specified additional HTTP headers.
    921      * <p>
    922      * Also see compatibility note on {@link #evaluateJavascript}.
    923      *
    924      * @param url the URL of the resource to load
    925      * @param additionalHttpHeaders the additional headers to be used in the
    926      *            HTTP request for this URL, specified as a map from name to
    927      *            value. Note that if this map contains any of the headers
    928      *            that are set by default by this WebView, such as those
    929      *            controlling caching, accept types or the User-Agent, their
    930      *            values may be overridden by this WebView's defaults.
    931      */
    932     public void loadUrl(String url, Map<String, String> additionalHttpHeaders) {
    933         checkThread();
    934         mProvider.loadUrl(url, additionalHttpHeaders);
    935     }
    936 
    937     /**
    938      * Loads the given URL.
    939      * <p>
    940      * Also see compatibility note on {@link #evaluateJavascript}.
    941      *
    942      * @param url the URL of the resource to load
    943      */
    944     public void loadUrl(String url) {
    945         checkThread();
    946         mProvider.loadUrl(url);
    947     }
    948 
    949     /**
    950      * Loads the URL with postData using "POST" method into this WebView. If url
    951      * is not a network URL, it will be loaded with {@link #loadUrl(String)}
    952      * instead, ignoring the postData param.
    953      *
    954      * @param url the URL of the resource to load
    955      * @param postData the data will be passed to "POST" request, which must be
    956      *     be "application/x-www-form-urlencoded" encoded.
    957      */
    958     public void postUrl(String url, byte[] postData) {
    959         checkThread();
    960         if (URLUtil.isNetworkUrl(url)) {
    961             mProvider.postUrl(url, postData);
    962         } else {
    963             mProvider.loadUrl(url);
    964         }
    965     }
    966 
    967     /**
    968      * Loads the given data into this WebView using a 'data' scheme URL.
    969      * <p>
    970      * Note that JavaScript's same origin policy means that script running in a
    971      * page loaded using this method will be unable to access content loaded
    972      * using any scheme other than 'data', including 'http(s)'. To avoid this
    973      * restriction, use {@link
    974      * #loadDataWithBaseURL(String,String,String,String,String)
    975      * loadDataWithBaseURL()} with an appropriate base URL.
    976      * <p>
    977      * The encoding parameter specifies whether the data is base64 or URL
    978      * encoded. If the data is base64 encoded, the value of the encoding
    979      * parameter must be 'base64'. For all other values of the parameter,
    980      * including null, it is assumed that the data uses ASCII encoding for
    981      * octets inside the range of safe URL characters and use the standard %xx
    982      * hex encoding of URLs for octets outside that range. For example, '#',
    983      * '%', '\', '?' should be replaced by %23, %25, %27, %3f respectively.
    984      * <p>
    985      * The 'data' scheme URL formed by this method uses the default US-ASCII
    986      * charset. If you need need to set a different charset, you should form a
    987      * 'data' scheme URL which explicitly specifies a charset parameter in the
    988      * mediatype portion of the URL and call {@link #loadUrl(String)} instead.
    989      * Note that the charset obtained from the mediatype portion of a data URL
    990      * always overrides that specified in the HTML or XML document itself.
    991      *
    992      * @param data a String of data in the given encoding
    993      * @param mimeType the MIME type of the data, e.g. 'text/html'
    994      * @param encoding the encoding of the data
    995      */
    996     public void loadData(String data, String mimeType, String encoding) {
    997         checkThread();
    998         mProvider.loadData(data, mimeType, encoding);
    999     }
   1000 
   1001     /**
   1002      * Loads the given data into this WebView, using baseUrl as the base URL for
   1003      * the content. The base URL is used both to resolve relative URLs and when
   1004      * applying JavaScript's same origin policy. The historyUrl is used for the
   1005      * history entry.
   1006      * <p>
   1007      * Note that content specified in this way can access local device files
   1008      * (via 'file' scheme URLs) only if baseUrl specifies a scheme other than
   1009      * 'http', 'https', 'ftp', 'ftps', 'about' or 'javascript'.
   1010      * <p>
   1011      * If the base URL uses the data scheme, this method is equivalent to
   1012      * calling {@link #loadData(String,String,String) loadData()} and the
   1013      * historyUrl is ignored, and the data will be treated as part of a data: URL.
   1014      * If the base URL uses any other scheme, then the data will be loaded into
   1015      * the WebView as a plain string (i.e. not part of a data URL) and any URL-encoded
   1016      * entities in the string will not be decoded.
   1017      * <p>
   1018      * Note that the baseUrl is sent in the 'Referer' HTTP header when
   1019      * requesting subresources (images, etc.) of the page loaded using this method.
   1020      *
   1021      * @param baseUrl the URL to use as the page's base URL. If null defaults to
   1022      *                'about:blank'.
   1023      * @param data a String of data in the given encoding
   1024      * @param mimeType the MIMEType of the data, e.g. 'text/html'. If null,
   1025      *                 defaults to 'text/html'.
   1026      * @param encoding the encoding of the data
   1027      * @param historyUrl the URL to use as the history entry. If null defaults
   1028      *                   to 'about:blank'. If non-null, this must be a valid URL.
   1029      */
   1030     public void loadDataWithBaseURL(String baseUrl, String data,
   1031             String mimeType, String encoding, String historyUrl) {
   1032         checkThread();
   1033         mProvider.loadDataWithBaseURL(baseUrl, data, mimeType, encoding, historyUrl);
   1034     }
   1035 
   1036     /**
   1037      * Asynchronously evaluates JavaScript in the context of the currently displayed page.
   1038      * If non-null, |resultCallback| will be invoked with any result returned from that
   1039      * execution. This method must be called on the UI thread and the callback will
   1040      * be made on the UI thread.
   1041      * <p>
   1042      * Compatibility note. Applications targeting {@link android.os.Build.VERSION_CODES#N} or
   1043      * later, JavaScript state from an empty WebView is no longer persisted across navigations like
   1044      * {@link #loadUrl(String)}. For example, global variables and functions defined before calling
   1045      * {@link #loadUrl(String)} will not exist in the loaded page. Applications should use
   1046      * {@link #addJavascriptInterface} instead to persist JavaScript objects across navigations.
   1047      *
   1048      * @param script the JavaScript to execute.
   1049      * @param resultCallback A callback to be invoked when the script execution
   1050      *                       completes with the result of the execution (if any).
   1051      *                       May be null if no notification of the result is required.
   1052      */
   1053     public void evaluateJavascript(String script, ValueCallback<String> resultCallback) {
   1054         checkThread();
   1055         mProvider.evaluateJavaScript(script, resultCallback);
   1056     }
   1057 
   1058     /**
   1059      * Saves the current view as a web archive.
   1060      *
   1061      * @param filename the filename where the archive should be placed
   1062      */
   1063     public void saveWebArchive(String filename) {
   1064         checkThread();
   1065         mProvider.saveWebArchive(filename);
   1066     }
   1067 
   1068     /**
   1069      * Saves the current view as a web archive.
   1070      *
   1071      * @param basename the filename where the archive should be placed
   1072      * @param autoname if false, takes basename to be a file. If true, basename
   1073      *                 is assumed to be a directory in which a filename will be
   1074      *                 chosen according to the URL of the current page.
   1075      * @param callback called after the web archive has been saved. The
   1076      *                 parameter for onReceiveValue will either be the filename
   1077      *                 under which the file was saved, or null if saving the
   1078      *                 file failed.
   1079      */
   1080     public void saveWebArchive(String basename, boolean autoname, ValueCallback<String> callback) {
   1081         checkThread();
   1082         mProvider.saveWebArchive(basename, autoname, callback);
   1083     }
   1084 
   1085     /**
   1086      * Stops the current load.
   1087      */
   1088     public void stopLoading() {
   1089         checkThread();
   1090         mProvider.stopLoading();
   1091     }
   1092 
   1093     /**
   1094      * Reloads the current URL.
   1095      */
   1096     public void reload() {
   1097         checkThread();
   1098         mProvider.reload();
   1099     }
   1100 
   1101     /**
   1102      * Gets whether this WebView has a back history item.
   1103      *
   1104      * @return true iff this WebView has a back history item
   1105      */
   1106     public boolean canGoBack() {
   1107         checkThread();
   1108         return mProvider.canGoBack();
   1109     }
   1110 
   1111     /**
   1112      * Goes back in the history of this WebView.
   1113      */
   1114     public void goBack() {
   1115         checkThread();
   1116         mProvider.goBack();
   1117     }
   1118 
   1119     /**
   1120      * Gets whether this WebView has a forward history item.
   1121      *
   1122      * @return true iff this WebView has a forward history item
   1123      */
   1124     public boolean canGoForward() {
   1125         checkThread();
   1126         return mProvider.canGoForward();
   1127     }
   1128 
   1129     /**
   1130      * Goes forward in the history of this WebView.
   1131      */
   1132     public void goForward() {
   1133         checkThread();
   1134         mProvider.goForward();
   1135     }
   1136 
   1137     /**
   1138      * Gets whether the page can go back or forward the given
   1139      * number of steps.
   1140      *
   1141      * @param steps the negative or positive number of steps to move the
   1142      *              history
   1143      */
   1144     public boolean canGoBackOrForward(int steps) {
   1145         checkThread();
   1146         return mProvider.canGoBackOrForward(steps);
   1147     }
   1148 
   1149     /**
   1150      * Goes to the history item that is the number of steps away from
   1151      * the current item. Steps is negative if backward and positive
   1152      * if forward.
   1153      *
   1154      * @param steps the number of steps to take back or forward in the back
   1155      *              forward list
   1156      */
   1157     public void goBackOrForward(int steps) {
   1158         checkThread();
   1159         mProvider.goBackOrForward(steps);
   1160     }
   1161 
   1162     /**
   1163      * Gets whether private browsing is enabled in this WebView.
   1164      */
   1165     public boolean isPrivateBrowsingEnabled() {
   1166         checkThread();
   1167         return mProvider.isPrivateBrowsingEnabled();
   1168     }
   1169 
   1170     /**
   1171      * Scrolls the contents of this WebView up by half the view size.
   1172      *
   1173      * @param top true to jump to the top of the page
   1174      * @return true if the page was scrolled
   1175      */
   1176     public boolean pageUp(boolean top) {
   1177         checkThread();
   1178         return mProvider.pageUp(top);
   1179     }
   1180 
   1181     /**
   1182      * Scrolls the contents of this WebView down by half the page size.
   1183      *
   1184      * @param bottom true to jump to bottom of page
   1185      * @return true if the page was scrolled
   1186      */
   1187     public boolean pageDown(boolean bottom) {
   1188         checkThread();
   1189         return mProvider.pageDown(bottom);
   1190     }
   1191 
   1192     /**
   1193      * Posts a {@link VisualStateCallback}, which will be called when
   1194      * the current state of the WebView is ready to be drawn.
   1195      *
   1196      * <p>Because updates to the DOM are processed asynchronously, updates to the DOM may not
   1197      * immediately be reflected visually by subsequent {@link WebView#onDraw} invocations. The
   1198      * {@link VisualStateCallback} provides a mechanism to notify the caller when the contents of
   1199      * the DOM at the current time are ready to be drawn the next time the {@link WebView}
   1200      * draws.</p>
   1201      *
   1202      * <p>The next draw after the callback completes is guaranteed to reflect all the updates to the
   1203      * DOM up to the point at which the {@link VisualStateCallback} was posted, but it may also
   1204      * contain updates applied after the callback was posted.</p>
   1205      *
   1206      * <p>The state of the DOM covered by this API includes the following:
   1207      * <ul>
   1208      * <li>primitive HTML elements (div, img, span, etc..)</li>
   1209      * <li>images</li>
   1210      * <li>CSS animations</li>
   1211      * <li>WebGL</li>
   1212      * <li>canvas</li>
   1213      * </ul>
   1214      * It does not include the state of:
   1215      * <ul>
   1216      * <li>the video tag</li>
   1217      * </ul></p>
   1218      *
   1219      * <p>To guarantee that the {@link WebView} will successfully render the first frame
   1220      * after the {@link VisualStateCallback#onComplete} method has been called a set of conditions
   1221      * must be met:
   1222      * <ul>
   1223      * <li>If the {@link WebView}'s visibility is set to {@link View#VISIBLE VISIBLE} then
   1224      * the {@link WebView} must be attached to the view hierarchy.</li>
   1225      * <li>If the {@link WebView}'s visibility is set to {@link View#INVISIBLE INVISIBLE}
   1226      * then the {@link WebView} must be attached to the view hierarchy and must be made
   1227      * {@link View#VISIBLE VISIBLE} from the {@link VisualStateCallback#onComplete} method.</li>
   1228      * <li>If the {@link WebView}'s visibility is set to {@link View#GONE GONE} then the
   1229      * {@link WebView} must be attached to the view hierarchy and its
   1230      * {@link AbsoluteLayout.LayoutParams LayoutParams}'s width and height need to be set to fixed
   1231      * values and must be made {@link View#VISIBLE VISIBLE} from the
   1232      * {@link VisualStateCallback#onComplete} method.</li>
   1233      * </ul></p>
   1234      *
   1235      * <p>When using this API it is also recommended to enable pre-rasterization if the {@link
   1236      * WebView} is off screen to avoid flickering. See {@link WebSettings#setOffscreenPreRaster} for
   1237      * more details and do consider its caveats.</p>
   1238      *
   1239      * @param requestId An id that will be returned in the callback to allow callers to match
   1240      *                  requests with callbacks.
   1241      * @param callback  The callback to be invoked.
   1242      */
   1243     public void postVisualStateCallback(long requestId, VisualStateCallback callback) {
   1244         checkThread();
   1245         mProvider.insertVisualStateCallback(requestId, callback);
   1246     }
   1247 
   1248     /**
   1249      * Clears this WebView so that onDraw() will draw nothing but white background,
   1250      * and onMeasure() will return 0 if MeasureSpec is not MeasureSpec.EXACTLY.
   1251      * @deprecated Use WebView.loadUrl("about:blank") to reliably reset the view state
   1252      *             and release page resources (including any running JavaScript).
   1253      */
   1254     @Deprecated
   1255     public void clearView() {
   1256         checkThread();
   1257         mProvider.clearView();
   1258     }
   1259 
   1260     /**
   1261      * Gets a new picture that captures the current contents of this WebView.
   1262      * The picture is of the entire document being displayed, and is not
   1263      * limited to the area currently displayed by this WebView. Also, the
   1264      * picture is a static copy and is unaffected by later changes to the
   1265      * content being displayed.
   1266      * <p>
   1267      * Note that due to internal changes, for API levels between
   1268      * {@link android.os.Build.VERSION_CODES#HONEYCOMB} and
   1269      * {@link android.os.Build.VERSION_CODES#ICE_CREAM_SANDWICH} inclusive, the
   1270      * picture does not include fixed position elements or scrollable divs.
   1271      * <p>
   1272      * Note that from {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1} the returned picture
   1273      * should only be drawn into bitmap-backed Canvas - using any other type of Canvas will involve
   1274      * additional conversion at a cost in memory and performance. Also the
   1275      * {@link android.graphics.Picture#createFromStream} and
   1276      * {@link android.graphics.Picture#writeToStream} methods are not supported on the
   1277      * returned object.
   1278      *
   1279      * @deprecated Use {@link #onDraw} to obtain a bitmap snapshot of the WebView, or
   1280      * {@link #saveWebArchive} to save the content to a file.
   1281      *
   1282      * @return a picture that captures the current contents of this WebView
   1283      */
   1284     @Deprecated
   1285     public Picture capturePicture() {
   1286         checkThread();
   1287         return mProvider.capturePicture();
   1288     }
   1289 
   1290     /**
   1291      * @deprecated Use {@link #createPrintDocumentAdapter(String)} which requires user
   1292      *             to provide a print document name.
   1293      */
   1294     @Deprecated
   1295     public PrintDocumentAdapter createPrintDocumentAdapter() {
   1296         checkThread();
   1297         return mProvider.createPrintDocumentAdapter("default");
   1298     }
   1299 
   1300     /**
   1301      * Creates a PrintDocumentAdapter that provides the content of this WebView for printing.
   1302      *
   1303      * The adapter works by converting the WebView contents to a PDF stream. The WebView cannot
   1304      * be drawn during the conversion process - any such draws are undefined. It is recommended
   1305      * to use a dedicated off screen WebView for the printing. If necessary, an application may
   1306      * temporarily hide a visible WebView by using a custom PrintDocumentAdapter instance
   1307      * wrapped around the object returned and observing the onStart and onFinish methods. See
   1308      * {@link android.print.PrintDocumentAdapter} for more information.
   1309      *
   1310      * @param documentName  The user-facing name of the printed document. See
   1311      *                      {@link android.print.PrintDocumentInfo}
   1312      */
   1313     public PrintDocumentAdapter createPrintDocumentAdapter(String documentName) {
   1314         checkThread();
   1315         return mProvider.createPrintDocumentAdapter(documentName);
   1316     }
   1317 
   1318     /**
   1319      * Gets the current scale of this WebView.
   1320      *
   1321      * @return the current scale
   1322      *
   1323      * @deprecated This method is prone to inaccuracy due to race conditions
   1324      * between the web rendering and UI threads; prefer
   1325      * {@link WebViewClient#onScaleChanged}.
   1326      */
   1327     @Deprecated
   1328     @ViewDebug.ExportedProperty(category = "webview")
   1329     public float getScale() {
   1330         checkThread();
   1331         return mProvider.getScale();
   1332     }
   1333 
   1334     /**
   1335      * Sets the initial scale for this WebView. 0 means default.
   1336      * The behavior for the default scale depends on the state of
   1337      * {@link WebSettings#getUseWideViewPort()} and
   1338      * {@link WebSettings#getLoadWithOverviewMode()}.
   1339      * If the content fits into the WebView control by width, then
   1340      * the zoom is set to 100%. For wide content, the behavior
   1341      * depends on the state of {@link WebSettings#getLoadWithOverviewMode()}.
   1342      * If its value is true, the content will be zoomed out to be fit
   1343      * by width into the WebView control, otherwise not.
   1344      *
   1345      * If initial scale is greater than 0, WebView starts with this value
   1346      * as initial scale.
   1347      * Please note that unlike the scale properties in the viewport meta tag,
   1348      * this method doesn't take the screen density into account.
   1349      *
   1350      * @param scaleInPercent the initial scale in percent
   1351      */
   1352     public void setInitialScale(int scaleInPercent) {
   1353         checkThread();
   1354         mProvider.setInitialScale(scaleInPercent);
   1355     }
   1356 
   1357     /**
   1358      * Invokes the graphical zoom picker widget for this WebView. This will
   1359      * result in the zoom widget appearing on the screen to control the zoom
   1360      * level of this WebView.
   1361      */
   1362     public void invokeZoomPicker() {
   1363         checkThread();
   1364         mProvider.invokeZoomPicker();
   1365     }
   1366 
   1367     /**
   1368      * Gets a HitTestResult based on the current cursor node. If a HTML::a
   1369      * tag is found and the anchor has a non-JavaScript URL, the HitTestResult
   1370      * type is set to SRC_ANCHOR_TYPE and the URL is set in the "extra" field.
   1371      * If the anchor does not have a URL or if it is a JavaScript URL, the type
   1372      * will be UNKNOWN_TYPE and the URL has to be retrieved through
   1373      * {@link #requestFocusNodeHref} asynchronously. If a HTML::img tag is
   1374      * found, the HitTestResult type is set to IMAGE_TYPE and the URL is set in
   1375      * the "extra" field. A type of
   1376      * SRC_IMAGE_ANCHOR_TYPE indicates an anchor with a URL that has an image as
   1377      * a child node. If a phone number is found, the HitTestResult type is set
   1378      * to PHONE_TYPE and the phone number is set in the "extra" field of
   1379      * HitTestResult. If a map address is found, the HitTestResult type is set
   1380      * to GEO_TYPE and the address is set in the "extra" field of HitTestResult.
   1381      * If an email address is found, the HitTestResult type is set to EMAIL_TYPE
   1382      * and the email is set in the "extra" field of HitTestResult. Otherwise,
   1383      * HitTestResult type is set to UNKNOWN_TYPE.
   1384      */
   1385     public HitTestResult getHitTestResult() {
   1386         checkThread();
   1387         return mProvider.getHitTestResult();
   1388     }
   1389 
   1390     /**
   1391      * Requests the anchor or image element URL at the last tapped point.
   1392      * If hrefMsg is null, this method returns immediately and does not
   1393      * dispatch hrefMsg to its target. If the tapped point hits an image,
   1394      * an anchor, or an image in an anchor, the message associates
   1395      * strings in named keys in its data. The value paired with the key
   1396      * may be an empty string.
   1397      *
   1398      * @param hrefMsg the message to be dispatched with the result of the
   1399      *                request. The message data contains three keys. "url"
   1400      *                returns the anchor's href attribute. "title" returns the
   1401      *                anchor's text. "src" returns the image's src attribute.
   1402      */
   1403     public void requestFocusNodeHref(Message hrefMsg) {
   1404         checkThread();
   1405         mProvider.requestFocusNodeHref(hrefMsg);
   1406     }
   1407 
   1408     /**
   1409      * Requests the URL of the image last touched by the user. msg will be sent
   1410      * to its target with a String representing the URL as its object.
   1411      *
   1412      * @param msg the message to be dispatched with the result of the request
   1413      *            as the data member with "url" as key. The result can be null.
   1414      */
   1415     public void requestImageRef(Message msg) {
   1416         checkThread();
   1417         mProvider.requestImageRef(msg);
   1418     }
   1419 
   1420     /**
   1421      * Gets the URL for the current page. This is not always the same as the URL
   1422      * passed to WebViewClient.onPageStarted because although the load for
   1423      * that URL has begun, the current page may not have changed.
   1424      *
   1425      * @return the URL for the current page
   1426      */
   1427     @ViewDebug.ExportedProperty(category = "webview")
   1428     public String getUrl() {
   1429         checkThread();
   1430         return mProvider.getUrl();
   1431     }
   1432 
   1433     /**
   1434      * Gets the original URL for the current page. This is not always the same
   1435      * as the URL passed to WebViewClient.onPageStarted because although the
   1436      * load for that URL has begun, the current page may not have changed.
   1437      * Also, there may have been redirects resulting in a different URL to that
   1438      * originally requested.
   1439      *
   1440      * @return the URL that was originally requested for the current page
   1441      */
   1442     @ViewDebug.ExportedProperty(category = "webview")
   1443     public String getOriginalUrl() {
   1444         checkThread();
   1445         return mProvider.getOriginalUrl();
   1446     }
   1447 
   1448     /**
   1449      * Gets the title for the current page. This is the title of the current page
   1450      * until WebViewClient.onReceivedTitle is called.
   1451      *
   1452      * @return the title for the current page
   1453      */
   1454     @ViewDebug.ExportedProperty(category = "webview")
   1455     public String getTitle() {
   1456         checkThread();
   1457         return mProvider.getTitle();
   1458     }
   1459 
   1460     /**
   1461      * Gets the favicon for the current page. This is the favicon of the current
   1462      * page until WebViewClient.onReceivedIcon is called.
   1463      *
   1464      * @return the favicon for the current page
   1465      */
   1466     public Bitmap getFavicon() {
   1467         checkThread();
   1468         return mProvider.getFavicon();
   1469     }
   1470 
   1471     /**
   1472      * Gets the touch icon URL for the apple-touch-icon <link> element, or
   1473      * a URL on this site's server pointing to the standard location of a
   1474      * touch icon.
   1475      *
   1476      * @hide
   1477      */
   1478     public String getTouchIconUrl() {
   1479         return mProvider.getTouchIconUrl();
   1480     }
   1481 
   1482     /**
   1483      * Gets the progress for the current page.
   1484      *
   1485      * @return the progress for the current page between 0 and 100
   1486      */
   1487     public int getProgress() {
   1488         checkThread();
   1489         return mProvider.getProgress();
   1490     }
   1491 
   1492     /**
   1493      * Gets the height of the HTML content.
   1494      *
   1495      * @return the height of the HTML content
   1496      */
   1497     @ViewDebug.ExportedProperty(category = "webview")
   1498     public int getContentHeight() {
   1499         checkThread();
   1500         return mProvider.getContentHeight();
   1501     }
   1502 
   1503     /**
   1504      * Gets the width of the HTML content.
   1505      *
   1506      * @return the width of the HTML content
   1507      * @hide
   1508      */
   1509     @ViewDebug.ExportedProperty(category = "webview")
   1510     public int getContentWidth() {
   1511         return mProvider.getContentWidth();
   1512     }
   1513 
   1514     /**
   1515      * Pauses all layout, parsing, and JavaScript timers for all WebViews. This
   1516      * is a global requests, not restricted to just this WebView. This can be
   1517      * useful if the application has been paused.
   1518      */
   1519     public void pauseTimers() {
   1520         checkThread();
   1521         mProvider.pauseTimers();
   1522     }
   1523 
   1524     /**
   1525      * Resumes all layout, parsing, and JavaScript timers for all WebViews.
   1526      * This will resume dispatching all timers.
   1527      */
   1528     public void resumeTimers() {
   1529         checkThread();
   1530         mProvider.resumeTimers();
   1531     }
   1532 
   1533     /**
   1534      * Does a best-effort attempt to pause any processing that can be paused
   1535      * safely, such as animations and geolocation. Note that this call
   1536      * does not pause JavaScript. To pause JavaScript globally, use
   1537      * {@link #pauseTimers}.
   1538      *
   1539      * To resume WebView, call {@link #onResume}.
   1540      */
   1541     public void onPause() {
   1542         checkThread();
   1543         mProvider.onPause();
   1544     }
   1545 
   1546     /**
   1547      * Resumes a WebView after a previous call to {@link #onPause}.
   1548      */
   1549     public void onResume() {
   1550         checkThread();
   1551         mProvider.onResume();
   1552     }
   1553 
   1554     /**
   1555      * Gets whether this WebView is paused, meaning onPause() was called.
   1556      * Calling onResume() sets the paused state back to false.
   1557      *
   1558      * @hide
   1559      */
   1560     public boolean isPaused() {
   1561         return mProvider.isPaused();
   1562     }
   1563 
   1564     /**
   1565      * Informs this WebView that memory is low so that it can free any available
   1566      * memory.
   1567      * @deprecated Memory caches are automatically dropped when no longer needed, and in response
   1568      *             to system memory pressure.
   1569      */
   1570     @Deprecated
   1571     public void freeMemory() {
   1572         checkThread();
   1573         mProvider.freeMemory();
   1574     }
   1575 
   1576     /**
   1577      * Clears the resource cache. Note that the cache is per-application, so
   1578      * this will clear the cache for all WebViews used.
   1579      *
   1580      * @param includeDiskFiles if false, only the RAM cache is cleared
   1581      */
   1582     public void clearCache(boolean includeDiskFiles) {
   1583         checkThread();
   1584         mProvider.clearCache(includeDiskFiles);
   1585     }
   1586 
   1587     /**
   1588      * Removes the autocomplete popup from the currently focused form field, if
   1589      * present. Note this only affects the display of the autocomplete popup,
   1590      * it does not remove any saved form data from this WebView's store. To do
   1591      * that, use {@link WebViewDatabase#clearFormData}.
   1592      */
   1593     public void clearFormData() {
   1594         checkThread();
   1595         mProvider.clearFormData();
   1596     }
   1597 
   1598     /**
   1599      * Tells this WebView to clear its internal back/forward list.
   1600      */
   1601     public void clearHistory() {
   1602         checkThread();
   1603         mProvider.clearHistory();
   1604     }
   1605 
   1606     /**
   1607      * Clears the SSL preferences table stored in response to proceeding with
   1608      * SSL certificate errors.
   1609      */
   1610     public void clearSslPreferences() {
   1611         checkThread();
   1612         mProvider.clearSslPreferences();
   1613     }
   1614 
   1615     /**
   1616      * Clears the client certificate preferences stored in response
   1617      * to proceeding/cancelling client cert requests. Note that WebView
   1618      * automatically clears these preferences when it receives a
   1619      * {@link KeyChain#ACTION_STORAGE_CHANGED} intent. The preferences are
   1620      * shared by all the WebViews that are created by the embedder application.
   1621      *
   1622      * @param onCleared  A runnable to be invoked when client certs are cleared.
   1623      *                   The embedder can pass null if not interested in the
   1624      *                   callback. The runnable will be called in UI thread.
   1625      */
   1626     public static void clearClientCertPreferences(Runnable onCleared) {
   1627         getFactory().getStatics().clearClientCertPreferences(onCleared);
   1628     }
   1629 
   1630     /**
   1631      * Starts Safe Browsing initialization.
   1632      * <p>
   1633      * URL loads are not guaranteed to be protected by Safe Browsing until after {@code callback} is
   1634      * invoked with {@code true}. Safe Browsing is not fully supported on all devices. For those
   1635      * devices {@code callback} will receive {@code false}.
   1636      * <p>
   1637      * This does not enable the Safe Browsing feature itself, and should only be called if Safe
   1638      * Browsing is enabled by the manifest tag or {@link WebSettings#setSafeBrowsingEnabled}. This
   1639      * prepares resources used for Safe Browsing.
   1640      * <p>
   1641      * This should be called with the Application Context (and will always use the Application
   1642      * context to do its work regardless).
   1643      *
   1644      * @param context Application Context.
   1645      * @param callback will be called on the UI thread with {@code true} if initialization is
   1646      * successful, {@code false} otherwise.
   1647      */
   1648     public static void startSafeBrowsing(Context context, ValueCallback<Boolean> callback) {
   1649         getFactory().getStatics().initSafeBrowsing(context, callback);
   1650     }
   1651 
   1652     /**
   1653      * Sets the list of domains that are exempt from SafeBrowsing checks. The list is
   1654      * global for all the WebViews.
   1655      * <p>
   1656      * Each rule should take one of these:
   1657      * <table>
   1658      * <tr><th> Rule </th> <th> Example </th> <th> Matches Subdomain</th> </tr>
   1659      * <tr><td> HOSTNAME </td> <td> example.com </td> <td> Yes </td> </tr>
   1660      * <tr><td> .HOSTNAME </td> <td> .example.com </td> <td> No </td> </tr>
   1661      * <tr><td> IPV4_LITERAL </td> <td> 192.168.1.1 </td> <td> No </td></tr>
   1662      * <tr><td> IPV6_LITERAL_WITH_BRACKETS </td><td>[10:20:30:40:50:60:70:80]</td><td>No</td></tr>
   1663      * </table>
   1664      * <p>
   1665      * All other rules, including wildcards, are invalid.
   1666      *
   1667      * @param urls the list of URLs
   1668      * @param callback will be called with true if URLs are successfully added to the whitelist.
   1669      * It will be called with false if any URLs are malformed. The callback will be run on
   1670      * the UI thread
   1671      */
   1672     public static void setSafeBrowsingWhitelist(@NonNull List<String> urls,
   1673             @Nullable ValueCallback<Boolean> callback) {
   1674         getFactory().getStatics().setSafeBrowsingWhitelist(urls, callback);
   1675     }
   1676 
   1677     /**
   1678      * Returns a URL pointing to the privacy policy for Safe Browsing reporting.
   1679      *
   1680      * @return the url pointing to a privacy policy document which can be displayed to users.
   1681      */
   1682     @NonNull
   1683     public static Uri getSafeBrowsingPrivacyPolicyUrl() {
   1684         return getFactory().getStatics().getSafeBrowsingPrivacyPolicyUrl();
   1685     }
   1686 
   1687     /**
   1688      * Gets the WebBackForwardList for this WebView. This contains the
   1689      * back/forward list for use in querying each item in the history stack.
   1690      * This is a copy of the private WebBackForwardList so it contains only a
   1691      * snapshot of the current state. Multiple calls to this method may return
   1692      * different objects. The object returned from this method will not be
   1693      * updated to reflect any new state.
   1694      */
   1695     public WebBackForwardList copyBackForwardList() {
   1696         checkThread();
   1697         return mProvider.copyBackForwardList();
   1698 
   1699     }
   1700 
   1701     /**
   1702      * Registers the listener to be notified as find-on-page operations
   1703      * progress. This will replace the current listener.
   1704      *
   1705      * @param listener an implementation of {@link FindListener}
   1706      */
   1707     public void setFindListener(FindListener listener) {
   1708         checkThread();
   1709         setupFindListenerIfNeeded();
   1710         mFindListener.mUserFindListener = listener;
   1711     }
   1712 
   1713     /**
   1714      * Highlights and scrolls to the next match found by
   1715      * {@link #findAllAsync}, wrapping around page boundaries as necessary.
   1716      * Notifies any registered {@link FindListener}. If {@link #findAllAsync(String)}
   1717      * has not been called yet, or if {@link #clearMatches} has been called since the
   1718      * last find operation, this function does nothing.
   1719      *
   1720      * @param forward the direction to search
   1721      * @see #setFindListener
   1722      */
   1723     public void findNext(boolean forward) {
   1724         checkThread();
   1725         mProvider.findNext(forward);
   1726     }
   1727 
   1728     /**
   1729      * Finds all instances of find on the page and highlights them.
   1730      * Notifies any registered {@link FindListener}.
   1731      *
   1732      * @param find the string to find
   1733      * @return the number of occurrences of the String "find" that were found
   1734      * @deprecated {@link #findAllAsync} is preferred.
   1735      * @see #setFindListener
   1736      */
   1737     @Deprecated
   1738     public int findAll(String find) {
   1739         checkThread();
   1740         StrictMode.noteSlowCall("findAll blocks UI: prefer findAllAsync");
   1741         return mProvider.findAll(find);
   1742     }
   1743 
   1744     /**
   1745      * Finds all instances of find on the page and highlights them,
   1746      * asynchronously. Notifies any registered {@link FindListener}.
   1747      * Successive calls to this will cancel any pending searches.
   1748      *
   1749      * @param find the string to find.
   1750      * @see #setFindListener
   1751      */
   1752     public void findAllAsync(String find) {
   1753         checkThread();
   1754         mProvider.findAllAsync(find);
   1755     }
   1756 
   1757     /**
   1758      * Starts an ActionMode for finding text in this WebView.  Only works if this
   1759      * WebView is attached to the view system.
   1760      *
   1761      * @param text if non-null, will be the initial text to search for.
   1762      *             Otherwise, the last String searched for in this WebView will
   1763      *             be used to start.
   1764      * @param showIme if true, show the IME, assuming the user will begin typing.
   1765      *                If false and text is non-null, perform a find all.
   1766      * @return true if the find dialog is shown, false otherwise
   1767      * @deprecated This method does not work reliably on all Android versions;
   1768      *             implementing a custom find dialog using WebView.findAllAsync()
   1769      *             provides a more robust solution.
   1770      */
   1771     @Deprecated
   1772     public boolean showFindDialog(String text, boolean showIme) {
   1773         checkThread();
   1774         return mProvider.showFindDialog(text, showIme);
   1775     }
   1776 
   1777     /**
   1778      * Gets the first substring consisting of the address of a physical
   1779      * location. Currently, only addresses in the United States are detected,
   1780      * and consist of:
   1781      * <ul>
   1782      *   <li>a house number</li>
   1783      *   <li>a street name</li>
   1784      *   <li>a street type (Road, Circle, etc), either spelled out or
   1785      *       abbreviated</li>
   1786      *   <li>a city name</li>
   1787      *   <li>a state or territory, either spelled out or two-letter abbr</li>
   1788      *   <li>an optional 5 digit or 9 digit zip code</li>
   1789      * </ul>
   1790      * All names must be correctly capitalized, and the zip code, if present,
   1791      * must be valid for the state. The street type must be a standard USPS
   1792      * spelling or abbreviation. The state or territory must also be spelled
   1793      * or abbreviated using USPS standards. The house number may not exceed
   1794      * five digits.
   1795      *
   1796      * @param addr the string to search for addresses
   1797      * @return the address, or if no address is found, null
   1798      */
   1799     public static String findAddress(String addr) {
   1800         // TODO: Rewrite this in Java so it is not needed to start up chromium
   1801         // Could also be deprecated
   1802         return getFactory().getStatics().findAddress(addr);
   1803     }
   1804 
   1805     /**
   1806      * For apps targeting the L release, WebView has a new default behavior that reduces
   1807      * memory footprint and increases performance by intelligently choosing
   1808      * the portion of the HTML document that needs to be drawn. These
   1809      * optimizations are transparent to the developers. However, under certain
   1810      * circumstances, an App developer may want to disable them:
   1811      * <ol>
   1812      *   <li>When an app uses {@link #onDraw} to do own drawing and accesses portions
   1813      *       of the page that is way outside the visible portion of the page.</li>
   1814      *   <li>When an app uses {@link #capturePicture} to capture a very large HTML document.
   1815      *       Note that capturePicture is a deprecated API.</li>
   1816      * </ol>
   1817      * Enabling drawing the entire HTML document has a significant performance
   1818      * cost. This method should be called before any WebViews are created.
   1819      */
   1820     public static void enableSlowWholeDocumentDraw() {
   1821         getFactory().getStatics().enableSlowWholeDocumentDraw();
   1822     }
   1823 
   1824     /**
   1825      * Clears the highlighting surrounding text matches created by
   1826      * {@link #findAllAsync}.
   1827      */
   1828     public void clearMatches() {
   1829         checkThread();
   1830         mProvider.clearMatches();
   1831     }
   1832 
   1833     /**
   1834      * Queries the document to see if it contains any image references. The
   1835      * message object will be dispatched with arg1 being set to 1 if images
   1836      * were found and 0 if the document does not reference any images.
   1837      *
   1838      * @param response the message that will be dispatched with the result
   1839      */
   1840     public void documentHasImages(Message response) {
   1841         checkThread();
   1842         mProvider.documentHasImages(response);
   1843     }
   1844 
   1845     /**
   1846      * Sets the WebViewClient that will receive various notifications and
   1847      * requests. This will replace the current handler.
   1848      *
   1849      * @param client an implementation of WebViewClient
   1850      * @see #getWebViewClient
   1851      */
   1852     public void setWebViewClient(WebViewClient client) {
   1853         checkThread();
   1854         mProvider.setWebViewClient(client);
   1855     }
   1856 
   1857     /**
   1858      * Gets the WebViewClient.
   1859      *
   1860      * @return the WebViewClient, or a default client if not yet set
   1861      * @see #setWebViewClient
   1862      */
   1863     public WebViewClient getWebViewClient() {
   1864         checkThread();
   1865         return mProvider.getWebViewClient();
   1866     }
   1867 
   1868     /**
   1869      * Registers the interface to be used when content can not be handled by
   1870      * the rendering engine, and should be downloaded instead. This will replace
   1871      * the current handler.
   1872      *
   1873      * @param listener an implementation of DownloadListener
   1874      */
   1875     public void setDownloadListener(DownloadListener listener) {
   1876         checkThread();
   1877         mProvider.setDownloadListener(listener);
   1878     }
   1879 
   1880     /**
   1881      * Sets the chrome handler. This is an implementation of WebChromeClient for
   1882      * use in handling JavaScript dialogs, favicons, titles, and the progress.
   1883      * This will replace the current handler.
   1884      *
   1885      * @param client an implementation of WebChromeClient
   1886      * @see #getWebChromeClient
   1887      */
   1888     public void setWebChromeClient(WebChromeClient client) {
   1889         checkThread();
   1890         mProvider.setWebChromeClient(client);
   1891     }
   1892 
   1893     /**
   1894      * Gets the chrome handler.
   1895      *
   1896      * @return the WebChromeClient, or null if not yet set
   1897      * @see #setWebChromeClient
   1898      */
   1899     public WebChromeClient getWebChromeClient() {
   1900         checkThread();
   1901         return mProvider.getWebChromeClient();
   1902     }
   1903 
   1904     /**
   1905      * Sets the Picture listener. This is an interface used to receive
   1906      * notifications of a new Picture.
   1907      *
   1908      * @param listener an implementation of WebView.PictureListener
   1909      * @deprecated This method is now obsolete.
   1910      */
   1911     @Deprecated
   1912     public void setPictureListener(PictureListener listener) {
   1913         checkThread();
   1914         mProvider.setPictureListener(listener);
   1915     }
   1916 
   1917     /**
   1918      * Injects the supplied Java object into this WebView. The object is
   1919      * injected into the JavaScript context of the main frame, using the
   1920      * supplied name. This allows the Java object's methods to be
   1921      * accessed from JavaScript. For applications targeted to API
   1922      * level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
   1923      * and above, only public methods that are annotated with
   1924      * {@link android.webkit.JavascriptInterface} can be accessed from JavaScript.
   1925      * For applications targeted to API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN} or below,
   1926      * all public methods (including the inherited ones) can be accessed, see the
   1927      * important security note below for implications.
   1928      * <p> Note that injected objects will not appear in JavaScript until the page is next
   1929      * (re)loaded. JavaScript should be enabled before injecting the object. For example:
   1930      * <pre>
   1931      * class JsObject {
   1932      *    {@literal @}JavascriptInterface
   1933      *    public String toString() { return "injectedObject"; }
   1934      * }
   1935      * webview.getSettings().setJavaScriptEnabled(true);
   1936      * webView.addJavascriptInterface(new JsObject(), "injectedObject");
   1937      * webView.loadData("<!DOCTYPE html><title></title>", "text/html", null);
   1938      * webView.loadUrl("javascript:alert(injectedObject.toString())");</pre>
   1939      * <p>
   1940      * <strong>IMPORTANT:</strong>
   1941      * <ul>
   1942      * <li> This method can be used to allow JavaScript to control the host
   1943      * application. This is a powerful feature, but also presents a security
   1944      * risk for apps targeting {@link android.os.Build.VERSION_CODES#JELLY_BEAN} or earlier.
   1945      * Apps that target a version later than {@link android.os.Build.VERSION_CODES#JELLY_BEAN}
   1946      * are still vulnerable if the app runs on a device running Android earlier than 4.2.
   1947      * The most secure way to use this method is to target {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
   1948      * and to ensure the method is called only when running on Android 4.2 or later.
   1949      * With these older versions, JavaScript could use reflection to access an
   1950      * injected object's public fields. Use of this method in a WebView
   1951      * containing untrusted content could allow an attacker to manipulate the
   1952      * host application in unintended ways, executing Java code with the
   1953      * permissions of the host application. Use extreme care when using this
   1954      * method in a WebView which could contain untrusted content.</li>
   1955      * <li> JavaScript interacts with Java object on a private, background
   1956      * thread of this WebView. Care is therefore required to maintain thread
   1957      * safety.
   1958      * </li>
   1959      * <li> The Java object's fields are not accessible.</li>
   1960      * <li> For applications targeted to API level {@link android.os.Build.VERSION_CODES#LOLLIPOP}
   1961      * and above, methods of injected Java objects are enumerable from
   1962      * JavaScript.</li>
   1963      * </ul>
   1964      *
   1965      * @param object the Java object to inject into this WebView's JavaScript
   1966      *               context. Null values are ignored.
   1967      * @param name the name used to expose the object in JavaScript
   1968      */
   1969     public void addJavascriptInterface(Object object, String name) {
   1970         checkThread();
   1971         mProvider.addJavascriptInterface(object, name);
   1972     }
   1973 
   1974     /**
   1975      * Removes a previously injected Java object from this WebView. Note that
   1976      * the removal will not be reflected in JavaScript until the page is next
   1977      * (re)loaded. See {@link #addJavascriptInterface}.
   1978      *
   1979      * @param name the name used to expose the object in JavaScript
   1980      */
   1981     public void removeJavascriptInterface(String name) {
   1982         checkThread();
   1983         mProvider.removeJavascriptInterface(name);
   1984     }
   1985 
   1986     /**
   1987      * Creates a message channel to communicate with JS and returns the message
   1988      * ports that represent the endpoints of this message channel. The HTML5 message
   1989      * channel functionality is described
   1990      * <a href="https://html.spec.whatwg.org/multipage/comms.html#messagechannel">here
   1991      * </a>
   1992      *
   1993      * <p>The returned message channels are entangled and already in started state.</p>
   1994      *
   1995      * @return the two message ports that form the message channel.
   1996      */
   1997     public WebMessagePort[] createWebMessageChannel() {
   1998         checkThread();
   1999         return mProvider.createWebMessageChannel();
   2000     }
   2001 
   2002     /**
   2003      * Post a message to main frame. The embedded application can restrict the
   2004      * messages to a certain target origin. See
   2005      * <a href="https://html.spec.whatwg.org/multipage/comms.html#posting-messages">
   2006      * HTML5 spec</a> for how target origin can be used.
   2007      * <p>
   2008      * A target origin can be set as a wildcard ("*"). However this is not recommended.
   2009      * See the page above for security issues.
   2010      *
   2011      * @param message the WebMessage
   2012      * @param targetOrigin the target origin.
   2013      */
   2014     public void postWebMessage(WebMessage message, Uri targetOrigin) {
   2015         checkThread();
   2016         mProvider.postMessageToMainFrame(message, targetOrigin);
   2017     }
   2018 
   2019     /**
   2020      * Gets the WebSettings object used to control the settings for this
   2021      * WebView.
   2022      *
   2023      * @return a WebSettings object that can be used to control this WebView's
   2024      *         settings
   2025      */
   2026     public WebSettings getSettings() {
   2027         checkThread();
   2028         return mProvider.getSettings();
   2029     }
   2030 
   2031     /**
   2032      * Enables debugging of web contents (HTML / CSS / JavaScript)
   2033      * loaded into any WebViews of this application. This flag can be enabled
   2034      * in order to facilitate debugging of web layouts and JavaScript
   2035      * code running inside WebViews. Please refer to WebView documentation
   2036      * for the debugging guide.
   2037      *
   2038      * The default is false.
   2039      *
   2040      * @param enabled whether to enable web contents debugging
   2041      */
   2042     public static void setWebContentsDebuggingEnabled(boolean enabled) {
   2043         getFactory().getStatics().setWebContentsDebuggingEnabled(enabled);
   2044     }
   2045 
   2046     /**
   2047      * Gets the list of currently loaded plugins.
   2048      *
   2049      * @return the list of currently loaded plugins
   2050      * @deprecated This was used for Gears, which has been deprecated.
   2051      * @hide
   2052      */
   2053     @Deprecated
   2054     public static synchronized PluginList getPluginList() {
   2055         return new PluginList();
   2056     }
   2057 
   2058     /**
   2059      * @deprecated This was used for Gears, which has been deprecated.
   2060      * @hide
   2061      */
   2062     @Deprecated
   2063     public void refreshPlugins(boolean reloadOpenPages) {
   2064         checkThread();
   2065     }
   2066 
   2067     /**
   2068      * Puts this WebView into text selection mode. Do not rely on this
   2069      * functionality; it will be deprecated in the future.
   2070      *
   2071      * @deprecated This method is now obsolete.
   2072      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
   2073      */
   2074     @Deprecated
   2075     public void emulateShiftHeld() {
   2076         checkThread();
   2077     }
   2078 
   2079     /**
   2080      * @deprecated WebView no longer needs to implement
   2081      * ViewGroup.OnHierarchyChangeListener.  This method does nothing now.
   2082      */
   2083     @Override
   2084     // Cannot add @hide as this can always be accessed via the interface.
   2085     @Deprecated
   2086     public void onChildViewAdded(View parent, View child) {}
   2087 
   2088     /**
   2089      * @deprecated WebView no longer needs to implement
   2090      * ViewGroup.OnHierarchyChangeListener.  This method does nothing now.
   2091      */
   2092     @Override
   2093     // Cannot add @hide as this can always be accessed via the interface.
   2094     @Deprecated
   2095     public void onChildViewRemoved(View p, View child) {}
   2096 
   2097     /**
   2098      * @deprecated WebView should not have implemented
   2099      * ViewTreeObserver.OnGlobalFocusChangeListener. This method does nothing now.
   2100      */
   2101     @Override
   2102     // Cannot add @hide as this can always be accessed via the interface.
   2103     @Deprecated
   2104     public void onGlobalFocusChanged(View oldFocus, View newFocus) {
   2105     }
   2106 
   2107     /**
   2108      * @deprecated Only the default case, true, will be supported in a future version.
   2109      */
   2110     @Deprecated
   2111     public void setMapTrackballToArrowKeys(boolean setMap) {
   2112         checkThread();
   2113         mProvider.setMapTrackballToArrowKeys(setMap);
   2114     }
   2115 
   2116 
   2117     public void flingScroll(int vx, int vy) {
   2118         checkThread();
   2119         mProvider.flingScroll(vx, vy);
   2120     }
   2121 
   2122     /**
   2123      * Gets the zoom controls for this WebView, as a separate View. The caller
   2124      * is responsible for inserting this View into the layout hierarchy.
   2125      * <p/>
   2126      * API level {@link android.os.Build.VERSION_CODES#CUPCAKE} introduced
   2127      * built-in zoom mechanisms for the WebView, as opposed to these separate
   2128      * zoom controls. The built-in mechanisms are preferred and can be enabled
   2129      * using {@link WebSettings#setBuiltInZoomControls}.
   2130      *
   2131      * @deprecated the built-in zoom mechanisms are preferred
   2132      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN}
   2133      */
   2134     @Deprecated
   2135     public View getZoomControls() {
   2136         checkThread();
   2137         return mProvider.getZoomControls();
   2138     }
   2139 
   2140     /**
   2141      * Gets whether this WebView can be zoomed in.
   2142      *
   2143      * @return true if this WebView can be zoomed in
   2144      *
   2145      * @deprecated This method is prone to inaccuracy due to race conditions
   2146      * between the web rendering and UI threads; prefer
   2147      * {@link WebViewClient#onScaleChanged}.
   2148      */
   2149     @Deprecated
   2150     public boolean canZoomIn() {
   2151         checkThread();
   2152         return mProvider.canZoomIn();
   2153     }
   2154 
   2155     /**
   2156      * Gets whether this WebView can be zoomed out.
   2157      *
   2158      * @return true if this WebView can be zoomed out
   2159      *
   2160      * @deprecated This method is prone to inaccuracy due to race conditions
   2161      * between the web rendering and UI threads; prefer
   2162      * {@link WebViewClient#onScaleChanged}.
   2163      */
   2164     @Deprecated
   2165     public boolean canZoomOut() {
   2166         checkThread();
   2167         return mProvider.canZoomOut();
   2168     }
   2169 
   2170     /**
   2171      * Performs a zoom operation in this WebView.
   2172      *
   2173      * @param zoomFactor the zoom factor to apply. The zoom factor will be clamped to the WebView's
   2174      * zoom limits. This value must be in the range 0.01 to 100.0 inclusive.
   2175      */
   2176     public void zoomBy(float zoomFactor) {
   2177         checkThread();
   2178         if (zoomFactor < 0.01)
   2179             throw new IllegalArgumentException("zoomFactor must be greater than 0.01.");
   2180         if (zoomFactor > 100.0)
   2181             throw new IllegalArgumentException("zoomFactor must be less than 100.");
   2182         mProvider.zoomBy(zoomFactor);
   2183     }
   2184 
   2185     /**
   2186      * Performs zoom in in this WebView.
   2187      *
   2188      * @return true if zoom in succeeds, false if no zoom changes
   2189      */
   2190     public boolean zoomIn() {
   2191         checkThread();
   2192         return mProvider.zoomIn();
   2193     }
   2194 
   2195     /**
   2196      * Performs zoom out in this WebView.
   2197      *
   2198      * @return true if zoom out succeeds, false if no zoom changes
   2199      */
   2200     public boolean zoomOut() {
   2201         checkThread();
   2202         return mProvider.zoomOut();
   2203     }
   2204 
   2205     /**
   2206      * @deprecated This method is now obsolete.
   2207      * @hide Since API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR1}
   2208      */
   2209     @Deprecated
   2210     public void debugDump() {
   2211         checkThread();
   2212     }
   2213 
   2214     /**
   2215      * See {@link ViewDebug.HierarchyHandler#dumpViewHierarchyWithProperties(BufferedWriter, int)}
   2216      * @hide
   2217      */
   2218     @Override
   2219     public void dumpViewHierarchyWithProperties(BufferedWriter out, int level) {
   2220         mProvider.dumpViewHierarchyWithProperties(out, level);
   2221     }
   2222 
   2223     /**
   2224      * See {@link ViewDebug.HierarchyHandler#findHierarchyView(String, int)}
   2225      * @hide
   2226      */
   2227     @Override
   2228     public View findHierarchyView(String className, int hashCode) {
   2229         return mProvider.findHierarchyView(className, hashCode);
   2230     }
   2231 
   2232     /** @hide */
   2233     @IntDef({
   2234         RENDERER_PRIORITY_WAIVED,
   2235         RENDERER_PRIORITY_BOUND,
   2236         RENDERER_PRIORITY_IMPORTANT
   2237     })
   2238     @Retention(RetentionPolicy.SOURCE)
   2239     public @interface RendererPriority {}
   2240 
   2241     /**
   2242      * The renderer associated with this WebView is bound with
   2243      * {@link Context#BIND_WAIVE_PRIORITY}. At this priority level
   2244      * {@link WebView} renderers will be strong targets for out of memory
   2245      * killing.
   2246      *
   2247      * Use with {@link #setRendererPriorityPolicy}.
   2248      */
   2249     public static final int RENDERER_PRIORITY_WAIVED = 0;
   2250     /**
   2251      * The renderer associated with this WebView is bound with
   2252      * the default priority for services.
   2253      *
   2254      * Use with {@link #setRendererPriorityPolicy}.
   2255      */
   2256     public static final int RENDERER_PRIORITY_BOUND = 1;
   2257     /**
   2258      * The renderer associated with this WebView is bound with
   2259      * {@link Context#BIND_IMPORTANT}.
   2260      *
   2261      * Use with {@link #setRendererPriorityPolicy}.
   2262      */
   2263     public static final int RENDERER_PRIORITY_IMPORTANT = 2;
   2264 
   2265     /**
   2266      * Set the renderer priority policy for this {@link WebView}. The
   2267      * priority policy will be used to determine whether an out of
   2268      * process renderer should be considered to be a target for OOM
   2269      * killing.
   2270      *
   2271      * Because a renderer can be associated with more than one
   2272      * WebView, the final priority it is computed as the maximum of
   2273      * any attached WebViews. When a WebView is destroyed it will
   2274      * cease to be considerered when calculating the renderer
   2275      * priority. Once no WebViews remain associated with the renderer,
   2276      * the priority of the renderer will be reduced to
   2277      * {@link #RENDERER_PRIORITY_WAIVED}.
   2278      *
   2279      * The default policy is to set the priority to
   2280      * {@link #RENDERER_PRIORITY_IMPORTANT} regardless of visibility,
   2281      * and this should not be changed unless the caller also handles
   2282      * renderer crashes with
   2283      * {@link WebViewClient#onRenderProcessGone}. Any other setting
   2284      * will result in WebView renderers being killed by the system
   2285      * more aggressively than the application.
   2286      *
   2287      * @param rendererRequestedPriority the minimum priority at which
   2288      *        this WebView desires the renderer process to be bound.
   2289      * @param waivedWhenNotVisible if true, this flag specifies that
   2290      *        when this WebView is not visible, it will be treated as
   2291      *        if it had requested a priority of
   2292      *        {@link #RENDERER_PRIORITY_WAIVED}.
   2293      */
   2294     public void setRendererPriorityPolicy(
   2295             @RendererPriority int rendererRequestedPriority,
   2296             boolean waivedWhenNotVisible) {
   2297         mProvider.setRendererPriorityPolicy(rendererRequestedPriority, waivedWhenNotVisible);
   2298     }
   2299 
   2300     /**
   2301      * Get the requested renderer priority for this WebView.
   2302      *
   2303      * @return the requested renderer priority policy.
   2304      */
   2305     @RendererPriority
   2306     public int getRendererRequestedPriority() {
   2307         return mProvider.getRendererRequestedPriority();
   2308     }
   2309 
   2310     /**
   2311      * Return whether this WebView requests a priority of
   2312      * {@link #RENDERER_PRIORITY_WAIVED} when not visible.
   2313      *
   2314      * @return whether this WebView requests a priority of
   2315      * {@link #RENDERER_PRIORITY_WAIVED} when not visible.
   2316      */
   2317     public boolean getRendererPriorityWaivedWhenNotVisible() {
   2318         return mProvider.getRendererPriorityWaivedWhenNotVisible();
   2319     }
   2320 
   2321     /**
   2322      * Sets the {@link TextClassifier} for this WebView.
   2323      */
   2324     public void setTextClassifier(@Nullable TextClassifier textClassifier) {
   2325         mProvider.setTextClassifier(textClassifier);
   2326     }
   2327 
   2328     /**
   2329      * Returns the {@link TextClassifier} used by this WebView.
   2330      * If no TextClassifier has been set, this WebView uses the default set by the system.
   2331      */
   2332     @NonNull
   2333     public TextClassifier getTextClassifier() {
   2334         return mProvider.getTextClassifier();
   2335     }
   2336 
   2337     //-------------------------------------------------------------------------
   2338     // Interface for WebView providers
   2339     //-------------------------------------------------------------------------
   2340 
   2341     /**
   2342      * Gets the WebViewProvider. Used by providers to obtain the underlying
   2343      * implementation, e.g. when the application responds to
   2344      * WebViewClient.onCreateWindow() request.
   2345      *
   2346      * @hide WebViewProvider is not public API.
   2347      */
   2348     @SystemApi
   2349     public WebViewProvider getWebViewProvider() {
   2350         return mProvider;
   2351     }
   2352 
   2353     /**
   2354      * Callback interface, allows the provider implementation to access non-public methods
   2355      * and fields, and make super-class calls in this WebView instance.
   2356      * @hide Only for use by WebViewProvider implementations
   2357      */
   2358     @SystemApi
   2359     public class PrivateAccess {
   2360         // ---- Access to super-class methods ----
   2361         public int super_getScrollBarStyle() {
   2362             return WebView.super.getScrollBarStyle();
   2363         }
   2364 
   2365         public void super_scrollTo(int scrollX, int scrollY) {
   2366             WebView.super.scrollTo(scrollX, scrollY);
   2367         }
   2368 
   2369         public void super_computeScroll() {
   2370             WebView.super.computeScroll();
   2371         }
   2372 
   2373         public boolean super_onHoverEvent(MotionEvent event) {
   2374             return WebView.super.onHoverEvent(event);
   2375         }
   2376 
   2377         public boolean super_performAccessibilityAction(int action, Bundle arguments) {
   2378             return WebView.super.performAccessibilityActionInternal(action, arguments);
   2379         }
   2380 
   2381         public boolean super_performLongClick() {
   2382             return WebView.super.performLongClick();
   2383         }
   2384 
   2385         public boolean super_setFrame(int left, int top, int right, int bottom) {
   2386             return WebView.super.setFrame(left, top, right, bottom);
   2387         }
   2388 
   2389         public boolean super_dispatchKeyEvent(KeyEvent event) {
   2390             return WebView.super.dispatchKeyEvent(event);
   2391         }
   2392 
   2393         public boolean super_onGenericMotionEvent(MotionEvent event) {
   2394             return WebView.super.onGenericMotionEvent(event);
   2395         }
   2396 
   2397         public boolean super_requestFocus(int direction, Rect previouslyFocusedRect) {
   2398             return WebView.super.requestFocus(direction, previouslyFocusedRect);
   2399         }
   2400 
   2401         public void super_setLayoutParams(ViewGroup.LayoutParams params) {
   2402             WebView.super.setLayoutParams(params);
   2403         }
   2404 
   2405         public void super_startActivityForResult(Intent intent, int requestCode) {
   2406             WebView.super.startActivityForResult(intent, requestCode);
   2407         }
   2408 
   2409         // ---- Access to non-public methods ----
   2410         public void overScrollBy(int deltaX, int deltaY,
   2411                 int scrollX, int scrollY,
   2412                 int scrollRangeX, int scrollRangeY,
   2413                 int maxOverScrollX, int maxOverScrollY,
   2414                 boolean isTouchEvent) {
   2415             WebView.this.overScrollBy(deltaX, deltaY, scrollX, scrollY, scrollRangeX, scrollRangeY,
   2416                     maxOverScrollX, maxOverScrollY, isTouchEvent);
   2417         }
   2418 
   2419         public void awakenScrollBars(int duration) {
   2420             WebView.this.awakenScrollBars(duration);
   2421         }
   2422 
   2423         public void awakenScrollBars(int duration, boolean invalidate) {
   2424             WebView.this.awakenScrollBars(duration, invalidate);
   2425         }
   2426 
   2427         public float getVerticalScrollFactor() {
   2428             return WebView.this.getVerticalScrollFactor();
   2429         }
   2430 
   2431         public float getHorizontalScrollFactor() {
   2432             return WebView.this.getHorizontalScrollFactor();
   2433         }
   2434 
   2435         public void setMeasuredDimension(int measuredWidth, int measuredHeight) {
   2436             WebView.this.setMeasuredDimension(measuredWidth, measuredHeight);
   2437         }
   2438 
   2439         public void onScrollChanged(int l, int t, int oldl, int oldt) {
   2440             WebView.this.onScrollChanged(l, t, oldl, oldt);
   2441         }
   2442 
   2443         public int getHorizontalScrollbarHeight() {
   2444             return WebView.this.getHorizontalScrollbarHeight();
   2445         }
   2446 
   2447         public void super_onDrawVerticalScrollBar(Canvas canvas, Drawable scrollBar,
   2448                 int l, int t, int r, int b) {
   2449             WebView.super.onDrawVerticalScrollBar(canvas, scrollBar, l, t, r, b);
   2450         }
   2451 
   2452         // ---- Access to (non-public) fields ----
   2453         /** Raw setter for the scroll X value, without invoking onScrollChanged handlers etc. */
   2454         public void setScrollXRaw(int scrollX) {
   2455             WebView.this.mScrollX = scrollX;
   2456         }
   2457 
   2458         /** Raw setter for the scroll Y value, without invoking onScrollChanged handlers etc. */
   2459         public void setScrollYRaw(int scrollY) {
   2460             WebView.this.mScrollY = scrollY;
   2461         }
   2462 
   2463     }
   2464 
   2465     //-------------------------------------------------------------------------
   2466     // Package-private internal stuff
   2467     //-------------------------------------------------------------------------
   2468 
   2469     // Only used by android.webkit.FindActionModeCallback.
   2470     void setFindDialogFindListener(FindListener listener) {
   2471         checkThread();
   2472         setupFindListenerIfNeeded();
   2473         mFindListener.mFindDialogFindListener = listener;
   2474     }
   2475 
   2476     // Only used by android.webkit.FindActionModeCallback.
   2477     void notifyFindDialogDismissed() {
   2478         checkThread();
   2479         mProvider.notifyFindDialogDismissed();
   2480     }
   2481 
   2482     //-------------------------------------------------------------------------
   2483     // Private internal stuff
   2484     //-------------------------------------------------------------------------
   2485 
   2486     private WebViewProvider mProvider;
   2487 
   2488     /**
   2489      * In addition to the FindListener that the user may set via the WebView.setFindListener
   2490      * API, FindActionModeCallback will register it's own FindListener. We keep them separate
   2491      * via this class so that the two FindListeners can potentially exist at once.
   2492      */
   2493     private class FindListenerDistributor implements FindListener {
   2494         private FindListener mFindDialogFindListener;
   2495         private FindListener mUserFindListener;
   2496 
   2497         @Override
   2498         public void onFindResultReceived(int activeMatchOrdinal, int numberOfMatches,
   2499                 boolean isDoneCounting) {
   2500             if (mFindDialogFindListener != null) {
   2501                 mFindDialogFindListener.onFindResultReceived(activeMatchOrdinal, numberOfMatches,
   2502                         isDoneCounting);
   2503             }
   2504 
   2505             if (mUserFindListener != null) {
   2506                 mUserFindListener.onFindResultReceived(activeMatchOrdinal, numberOfMatches,
   2507                         isDoneCounting);
   2508             }
   2509         }
   2510     }
   2511     private FindListenerDistributor mFindListener;
   2512 
   2513     private void setupFindListenerIfNeeded() {
   2514         if (mFindListener == null) {
   2515             mFindListener = new FindListenerDistributor();
   2516             mProvider.setFindListener(mFindListener);
   2517         }
   2518     }
   2519 
   2520     private void ensureProviderCreated() {
   2521         checkThread();
   2522         if (mProvider == null) {
   2523             // As this can get called during the base class constructor chain, pass the minimum
   2524             // number of dependencies here; the rest are deferred to init().
   2525             mProvider = getFactory().createWebView(this, new PrivateAccess());
   2526         }
   2527     }
   2528 
   2529     private static WebViewFactoryProvider getFactory() {
   2530         return WebViewFactory.getProvider();
   2531     }
   2532 
   2533     private final Looper mWebViewThread = Looper.myLooper();
   2534 
   2535     private void checkThread() {
   2536         // Ignore mWebViewThread == null because this can be called during in the super class
   2537         // constructor, before this class's own constructor has even started.
   2538         if (mWebViewThread != null && Looper.myLooper() != mWebViewThread) {
   2539             Throwable throwable = new Throwable(
   2540                     "A WebView method was called on thread '" +
   2541                     Thread.currentThread().getName() + "'. " +
   2542                     "All WebView methods must be called on the same thread. " +
   2543                     "(Expected Looper " + mWebViewThread + " called on " + Looper.myLooper() +
   2544                     ", FYI main Looper is " + Looper.getMainLooper() + ")");
   2545             Log.w(LOGTAG, Log.getStackTraceString(throwable));
   2546             StrictMode.onWebViewMethodCalledOnWrongThread(throwable);
   2547 
   2548             if (sEnforceThreadChecking) {
   2549                 throw new RuntimeException(throwable);
   2550             }
   2551         }
   2552     }
   2553 
   2554     //-------------------------------------------------------------------------
   2555     // Override View methods
   2556     //-------------------------------------------------------------------------
   2557 
   2558     // TODO: Add a test that enumerates all methods in ViewDelegte & ScrollDelegate, and ensures
   2559     // there's a corresponding override (or better, caller) for each of them in here.
   2560 
   2561     @Override
   2562     protected void onAttachedToWindow() {
   2563         super.onAttachedToWindow();
   2564         mProvider.getViewDelegate().onAttachedToWindow();
   2565     }
   2566 
   2567     /** @hide */
   2568     @Override
   2569     protected void onDetachedFromWindowInternal() {
   2570         mProvider.getViewDelegate().onDetachedFromWindow();
   2571         super.onDetachedFromWindowInternal();
   2572     }
   2573 
   2574     /** @hide */
   2575     @Override
   2576     public void onMovedToDisplay(int displayId, Configuration config) {
   2577         mProvider.getViewDelegate().onMovedToDisplay(displayId, config);
   2578     }
   2579 
   2580     @Override
   2581     public void setLayoutParams(ViewGroup.LayoutParams params) {
   2582         mProvider.getViewDelegate().setLayoutParams(params);
   2583     }
   2584 
   2585     @Override
   2586     public void setOverScrollMode(int mode) {
   2587         super.setOverScrollMode(mode);
   2588         // This method may be called in the constructor chain, before the WebView provider is
   2589         // created.
   2590         ensureProviderCreated();
   2591         mProvider.getViewDelegate().setOverScrollMode(mode);
   2592     }
   2593 
   2594     @Override
   2595     public void setScrollBarStyle(int style) {
   2596         mProvider.getViewDelegate().setScrollBarStyle(style);
   2597         super.setScrollBarStyle(style);
   2598     }
   2599 
   2600     @Override
   2601     protected int computeHorizontalScrollRange() {
   2602         return mProvider.getScrollDelegate().computeHorizontalScrollRange();
   2603     }
   2604 
   2605     @Override
   2606     protected int computeHorizontalScrollOffset() {
   2607         return mProvider.getScrollDelegate().computeHorizontalScrollOffset();
   2608     }
   2609 
   2610     @Override
   2611     protected int computeVerticalScrollRange() {
   2612         return mProvider.getScrollDelegate().computeVerticalScrollRange();
   2613     }
   2614 
   2615     @Override
   2616     protected int computeVerticalScrollOffset() {
   2617         return mProvider.getScrollDelegate().computeVerticalScrollOffset();
   2618     }
   2619 
   2620     @Override
   2621     protected int computeVerticalScrollExtent() {
   2622         return mProvider.getScrollDelegate().computeVerticalScrollExtent();
   2623     }
   2624 
   2625     @Override
   2626     public void computeScroll() {
   2627         mProvider.getScrollDelegate().computeScroll();
   2628     }
   2629 
   2630     @Override
   2631     public boolean onHoverEvent(MotionEvent event) {
   2632         return mProvider.getViewDelegate().onHoverEvent(event);
   2633     }
   2634 
   2635     @Override
   2636     public boolean onTouchEvent(MotionEvent event) {
   2637         return mProvider.getViewDelegate().onTouchEvent(event);
   2638     }
   2639 
   2640     @Override
   2641     public boolean onGenericMotionEvent(MotionEvent event) {
   2642         return mProvider.getViewDelegate().onGenericMotionEvent(event);
   2643     }
   2644 
   2645     @Override
   2646     public boolean onTrackballEvent(MotionEvent event) {
   2647         return mProvider.getViewDelegate().onTrackballEvent(event);
   2648     }
   2649 
   2650     @Override
   2651     public boolean onKeyDown(int keyCode, KeyEvent event) {
   2652         return mProvider.getViewDelegate().onKeyDown(keyCode, event);
   2653     }
   2654 
   2655     @Override
   2656     public boolean onKeyUp(int keyCode, KeyEvent event) {
   2657         return mProvider.getViewDelegate().onKeyUp(keyCode, event);
   2658     }
   2659 
   2660     @Override
   2661     public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) {
   2662         return mProvider.getViewDelegate().onKeyMultiple(keyCode, repeatCount, event);
   2663     }
   2664 
   2665     /*
   2666     TODO: These are not currently implemented in WebViewClassic, but it seems inconsistent not
   2667     to be delegating them too.
   2668 
   2669     @Override
   2670     public boolean onKeyPreIme(int keyCode, KeyEvent event) {
   2671         return mProvider.getViewDelegate().onKeyPreIme(keyCode, event);
   2672     }
   2673     @Override
   2674     public boolean onKeyLongPress(int keyCode, KeyEvent event) {
   2675         return mProvider.getViewDelegate().onKeyLongPress(keyCode, event);
   2676     }
   2677     @Override
   2678     public boolean onKeyShortcut(int keyCode, KeyEvent event) {
   2679         return mProvider.getViewDelegate().onKeyShortcut(keyCode, event);
   2680     }
   2681     */
   2682 
   2683     @Override
   2684     public AccessibilityNodeProvider getAccessibilityNodeProvider() {
   2685         AccessibilityNodeProvider provider =
   2686                 mProvider.getViewDelegate().getAccessibilityNodeProvider();
   2687         return provider == null ? super.getAccessibilityNodeProvider() : provider;
   2688     }
   2689 
   2690     @Deprecated
   2691     @Override
   2692     public boolean shouldDelayChildPressedState() {
   2693         return mProvider.getViewDelegate().shouldDelayChildPressedState();
   2694     }
   2695 
   2696     @Override
   2697     public CharSequence getAccessibilityClassName() {
   2698         return WebView.class.getName();
   2699     }
   2700 
   2701     @Override
   2702     public void onProvideVirtualStructure(ViewStructure structure) {
   2703         mProvider.getViewDelegate().onProvideVirtualStructure(structure);
   2704     }
   2705 
   2706     /**
   2707      * {@inheritDoc}
   2708      *
   2709      * <p>The {@link ViewStructure} traditionally represents a {@link View}, while for web pages
   2710      * it represent HTML nodes. Hence, it's necessary to "map" the HTML properties in a way that is
   2711      * understood by the {@link android.service.autofill.AutofillService} implementations:
   2712      *
   2713      * <ol>
   2714      *   <li>Only the HTML nodes inside a {@code FORM} are generated.
   2715      *   <li>The source of the HTML is set using {@link ViewStructure#setWebDomain(String)} in the
   2716      *   node representing the WebView.
   2717      *   <li>If a web page has multiple {@code FORM}s, only the data for the current form is
   2718      *   represented&mdash;if the user taps a field from another form, then the current autofill
   2719      *   context is canceled (by calling {@link android.view.autofill.AutofillManager#cancel()} and
   2720      *   a new context is created for that {@code FORM}.
   2721      *   <li>Similarly, if the page has {@code IFRAME} nodes, they are not initially represented in
   2722      *   the view structure until the user taps a field from a {@code FORM} inside the
   2723      *   {@code IFRAME}, in which case it would be treated the same way as multiple forms described
   2724      *   above, except that the {@link ViewStructure#setWebDomain(String) web domain} of the
   2725      *   {@code FORM} contains the {@code src} attribute from the {@code IFRAME} node.
   2726      *   <li>The W3C autofill field ({@code autocomplete} tag attribute) maps to
   2727      *   {@link ViewStructure#setAutofillHints(String[])}.
   2728      *   <li>If the view is editable, the {@link ViewStructure#setAutofillType(int)} and
   2729      *   {@link ViewStructure#setAutofillValue(AutofillValue)} must be set.
   2730      *   <li>The {@code placeholder} attribute maps to {@link ViewStructure#setHint(CharSequence)}.
   2731      *   <li>Other HTML attributes can be represented through
   2732      *   {@link ViewStructure#setHtmlInfo(android.view.ViewStructure.HtmlInfo)}.
   2733      * </ol>
   2734      *
   2735      * <p>If the WebView implementation can determine that the value of a field was set statically
   2736      * (for example, not through Javascript), it should also call
   2737      * {@code structure.setDataIsSensitive(false)}.
   2738      *
   2739      * <p>For example, an HTML form with 2 fields for username and password:
   2740      *
   2741      * <pre class="prettyprint">
   2742      *    &lt;input type="text" name="username" id="user" value="Type your username" autocomplete="username" placeholder="Email or username"&gt;
   2743      *    &lt;input type="password" name="password" id="pass" autocomplete="current-password" placeholder="Password"&gt;
   2744      * </pre>
   2745      *
   2746      * <p>Would map to:
   2747      *
   2748      * <pre class="prettyprint">
   2749      *     int index = structure.addChildCount(2);
   2750      *     ViewStructure username = structure.newChild(index);
   2751      *     username.setAutofillId(structure.getAutofillId(), 1); // id 1 - first child
   2752      *     username.setAutofillHints("username");
   2753      *     username.setHtmlInfo(username.newHtmlInfoBuilder("input")
   2754      *         .addAttribute("type", "text")
   2755      *         .addAttribute("name", "username")
   2756      *         .build());
   2757      *     username.setHint("Email or username");
   2758      *     username.setAutofillType(View.AUTOFILL_TYPE_TEXT);
   2759      *     username.setAutofillValue(AutofillValue.forText("Type your username"));
   2760      *     // Value of the field is not sensitive because it was created statically and not changed.
   2761      *     username.setDataIsSensitive(false);
   2762      *
   2763      *     ViewStructure password = structure.newChild(index + 1);
   2764      *     username.setAutofillId(structure, 2); // id 2 - second child
   2765      *     password.setAutofillHints("current-password");
   2766      *     password.setHtmlInfo(password.newHtmlInfoBuilder("input")
   2767      *         .addAttribute("type", "password")
   2768      *         .addAttribute("name", "password")
   2769      *         .build());
   2770      *     password.setHint("Password");
   2771      *     password.setAutofillType(View.AUTOFILL_TYPE_TEXT);
   2772      * </pre>
   2773      */
   2774     @Override
   2775     public void onProvideAutofillVirtualStructure(ViewStructure structure, int flags) {
   2776         mProvider.getViewDelegate().onProvideAutofillVirtualStructure(structure, flags);
   2777     }
   2778 
   2779     @Override
   2780     public void autofill(SparseArray<AutofillValue>values) {
   2781         mProvider.getViewDelegate().autofill(values);
   2782     }
   2783 
   2784     /** @hide */
   2785     @Override
   2786     public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) {
   2787         super.onInitializeAccessibilityNodeInfoInternal(info);
   2788         mProvider.getViewDelegate().onInitializeAccessibilityNodeInfo(info);
   2789     }
   2790 
   2791     /** @hide */
   2792     @Override
   2793     public void onInitializeAccessibilityEventInternal(AccessibilityEvent event) {
   2794         super.onInitializeAccessibilityEventInternal(event);
   2795         mProvider.getViewDelegate().onInitializeAccessibilityEvent(event);
   2796     }
   2797 
   2798     /** @hide */
   2799     @Override
   2800     public boolean performAccessibilityActionInternal(int action, Bundle arguments) {
   2801         return mProvider.getViewDelegate().performAccessibilityAction(action, arguments);
   2802     }
   2803 
   2804     /** @hide */
   2805     @Override
   2806     protected void onDrawVerticalScrollBar(Canvas canvas, Drawable scrollBar,
   2807             int l, int t, int r, int b) {
   2808         mProvider.getViewDelegate().onDrawVerticalScrollBar(canvas, scrollBar, l, t, r, b);
   2809     }
   2810 
   2811     @Override
   2812     protected void onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY) {
   2813         mProvider.getViewDelegate().onOverScrolled(scrollX, scrollY, clampedX, clampedY);
   2814     }
   2815 
   2816     @Override
   2817     protected void onWindowVisibilityChanged(int visibility) {
   2818         super.onWindowVisibilityChanged(visibility);
   2819         mProvider.getViewDelegate().onWindowVisibilityChanged(visibility);
   2820     }
   2821 
   2822     @Override
   2823     protected void onDraw(Canvas canvas) {
   2824         mProvider.getViewDelegate().onDraw(canvas);
   2825     }
   2826 
   2827     @Override
   2828     public boolean performLongClick() {
   2829         return mProvider.getViewDelegate().performLongClick();
   2830     }
   2831 
   2832     @Override
   2833     protected void onConfigurationChanged(Configuration newConfig) {
   2834         mProvider.getViewDelegate().onConfigurationChanged(newConfig);
   2835     }
   2836 
   2837     /**
   2838      * Creates a new InputConnection for an InputMethod to interact with the WebView.
   2839      * This is similar to {@link View#onCreateInputConnection} but note that WebView
   2840      * calls InputConnection methods on a thread other than the UI thread.
   2841      * If these methods are overridden, then the overriding methods should respect
   2842      * thread restrictions when calling View methods or accessing data.
   2843      */
   2844     @Override
   2845     public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
   2846         return mProvider.getViewDelegate().onCreateInputConnection(outAttrs);
   2847     }
   2848 
   2849     @Override
   2850     public boolean onDragEvent(DragEvent event) {
   2851         return mProvider.getViewDelegate().onDragEvent(event);
   2852     }
   2853 
   2854     @Override
   2855     protected void onVisibilityChanged(View changedView, int visibility) {
   2856         super.onVisibilityChanged(changedView, visibility);
   2857         // This method may be called in the constructor chain, before the WebView provider is
   2858         // created.
   2859         ensureProviderCreated();
   2860         mProvider.getViewDelegate().onVisibilityChanged(changedView, visibility);
   2861     }
   2862 
   2863     @Override
   2864     public void onWindowFocusChanged(boolean hasWindowFocus) {
   2865         mProvider.getViewDelegate().onWindowFocusChanged(hasWindowFocus);
   2866         super.onWindowFocusChanged(hasWindowFocus);
   2867     }
   2868 
   2869     @Override
   2870     protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
   2871         mProvider.getViewDelegate().onFocusChanged(focused, direction, previouslyFocusedRect);
   2872         super.onFocusChanged(focused, direction, previouslyFocusedRect);
   2873     }
   2874 
   2875     /** @hide */
   2876     @Override
   2877     protected boolean setFrame(int left, int top, int right, int bottom) {
   2878         return mProvider.getViewDelegate().setFrame(left, top, right, bottom);
   2879     }
   2880 
   2881     @Override
   2882     protected void onSizeChanged(int w, int h, int ow, int oh) {
   2883         super.onSizeChanged(w, h, ow, oh);
   2884         mProvider.getViewDelegate().onSizeChanged(w, h, ow, oh);
   2885     }
   2886 
   2887     @Override
   2888     protected void onScrollChanged(int l, int t, int oldl, int oldt) {
   2889         super.onScrollChanged(l, t, oldl, oldt);
   2890         mProvider.getViewDelegate().onScrollChanged(l, t, oldl, oldt);
   2891     }
   2892 
   2893     @Override
   2894     public boolean dispatchKeyEvent(KeyEvent event) {
   2895         return mProvider.getViewDelegate().dispatchKeyEvent(event);
   2896     }
   2897 
   2898     @Override
   2899     public boolean requestFocus(int direction, Rect previouslyFocusedRect) {
   2900         return mProvider.getViewDelegate().requestFocus(direction, previouslyFocusedRect);
   2901     }
   2902 
   2903     @Override
   2904     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
   2905         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
   2906         mProvider.getViewDelegate().onMeasure(widthMeasureSpec, heightMeasureSpec);
   2907     }
   2908 
   2909     @Override
   2910     public boolean requestChildRectangleOnScreen(View child, Rect rect, boolean immediate) {
   2911         return mProvider.getViewDelegate().requestChildRectangleOnScreen(child, rect, immediate);
   2912     }
   2913 
   2914     @Override
   2915     public void setBackgroundColor(int color) {
   2916         mProvider.getViewDelegate().setBackgroundColor(color);
   2917     }
   2918 
   2919     @Override
   2920     public void setLayerType(int layerType, Paint paint) {
   2921         super.setLayerType(layerType, paint);
   2922         mProvider.getViewDelegate().setLayerType(layerType, paint);
   2923     }
   2924 
   2925     @Override
   2926     protected void dispatchDraw(Canvas canvas) {
   2927         mProvider.getViewDelegate().preDispatchDraw(canvas);
   2928         super.dispatchDraw(canvas);
   2929     }
   2930 
   2931     @Override
   2932     public void onStartTemporaryDetach() {
   2933         super.onStartTemporaryDetach();
   2934         mProvider.getViewDelegate().onStartTemporaryDetach();
   2935     }
   2936 
   2937     @Override
   2938     public void onFinishTemporaryDetach() {
   2939         super.onFinishTemporaryDetach();
   2940         mProvider.getViewDelegate().onFinishTemporaryDetach();
   2941     }
   2942 
   2943     @Override
   2944     public Handler getHandler() {
   2945         return mProvider.getViewDelegate().getHandler(super.getHandler());
   2946     }
   2947 
   2948     @Override
   2949     public View findFocus() {
   2950         return mProvider.getViewDelegate().findFocus(super.findFocus());
   2951     }
   2952 
   2953     /**
   2954      * If WebView has already been loaded into the current process this method will return the
   2955      * package that was used to load it. Otherwise, the package that would be used if the WebView
   2956      * was loaded right now will be returned; this does not cause WebView to be loaded, so this
   2957      * information may become outdated at any time.
   2958      * The WebView package changes either when the current WebView package is updated, disabled, or
   2959      * uninstalled. It can also be changed through a Developer Setting.
   2960      * If the WebView package changes, any app process that has loaded WebView will be killed. The
   2961      * next time the app starts and loads WebView it will use the new WebView package instead.
   2962      * @return the current WebView package, or null if there is none.
   2963      */
   2964     public static PackageInfo getCurrentWebViewPackage() {
   2965         PackageInfo webviewPackage = WebViewFactory.getLoadedPackageInfo();
   2966         if (webviewPackage != null) {
   2967             return webviewPackage;
   2968         }
   2969 
   2970         try {
   2971             return WebViewFactory.getUpdateService().getCurrentWebViewPackage();
   2972         } catch (RemoteException e) {
   2973             throw e.rethrowFromSystemServer();
   2974         }
   2975     }
   2976 
   2977     /**
   2978      * Receive the result from a previous call to {@link #startActivityForResult(Intent, int)}.
   2979      *
   2980      * @param requestCode The integer request code originally supplied to
   2981      *                    startActivityForResult(), allowing you to identify who this
   2982      *                    result came from.
   2983      * @param resultCode The integer result code returned by the child activity
   2984      *                   through its setResult().
   2985      * @param data An Intent, which can return result data to the caller
   2986      *               (various data can be attached to Intent "extras").
   2987      * @hide
   2988      */
   2989     @Override
   2990     public void onActivityResult(int requestCode, int resultCode, Intent data) {
   2991         mProvider.getViewDelegate().onActivityResult(requestCode, resultCode, data);
   2992     }
   2993 
   2994     /** @hide */
   2995     @Override
   2996     protected void encodeProperties(@NonNull ViewHierarchyEncoder encoder) {
   2997         super.encodeProperties(encoder);
   2998 
   2999         checkThread();
   3000         encoder.addProperty("webview:contentHeight", mProvider.getContentHeight());
   3001         encoder.addProperty("webview:contentWidth", mProvider.getContentWidth());
   3002         encoder.addProperty("webview:scale", mProvider.getScale());
   3003         encoder.addProperty("webview:title", mProvider.getTitle());
   3004         encoder.addProperty("webview:url", mProvider.getUrl());
   3005         encoder.addProperty("webview:originalUrl", mProvider.getOriginalUrl());
   3006     }
   3007 }
   3008