Home | History | Annotate | Download | only in webkit 
      1 /*
      2  * Copyright (C) 2014 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.SystemApi;
     20 import android.app.ActivityThread;
     21 import android.app.Application;
     22 import android.content.Context;
     23 import android.content.res.Resources;
     24 import android.graphics.Canvas;
     25 import android.os.SystemProperties;
     26 import android.os.Trace;
     27 import android.util.SparseArray;
     28 import android.view.DisplayListCanvas;
     29 import android.view.View;
     30 import android.view.ViewRootImpl;
     31 
     32 /**
     33  * Delegate used by the WebView provider implementation to access
     34  * the required framework functionality needed to implement a {@link WebView}.
     35  *
     36  * @hide
     37  */
     38 @SystemApi
     39 public final class WebViewDelegate {
     40 
     41     /* package */ WebViewDelegate() { }
     42 
     43     /**
     44      * Listener that gets notified whenever tracing has been enabled/disabled.
     45      */
     46     public interface OnTraceEnabledChangeListener {
     47         void onTraceEnabledChange(boolean enabled);
     48     }
     49 
     50     /**
     51      * Register a callback to be invoked when tracing for the WebView component has been
     52      * enabled/disabled.
     53      */
     54     public void setOnTraceEnabledChangeListener(final OnTraceEnabledChangeListener listener) {
     55         SystemProperties.addChangeCallback(new Runnable() {
     56             @Override
     57             public void run() {
     58                 listener.onTraceEnabledChange(isTraceTagEnabled());
     59             }
     60         });
     61     }
     62 
     63     /**
     64      * Returns true if the WebView trace tag is enabled and false otherwise.
     65      */
     66     public boolean isTraceTagEnabled() {
     67         return Trace.isTagEnabled(Trace.TRACE_TAG_WEBVIEW);
     68     }
     69 
     70     /**
     71      * Returns true if the draw GL functor can be invoked (see {@link #invokeDrawGlFunctor})
     72      * and false otherwise.
     73      */
     74     public boolean canInvokeDrawGlFunctor(View containerView) {
     75         ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
     76          // viewRootImpl can be null during teardown when window is leaked.
     77         return viewRootImpl != null;
     78     }
     79 
     80     /**
     81      * Invokes the draw GL functor. If waitForCompletion is false the functor
     82      * may be invoked asynchronously.
     83      *
     84      * @param nativeDrawGLFunctor the pointer to the native functor that implements
     85      *        system/core/include/utils/Functor.h
     86      */
     87     public void invokeDrawGlFunctor(View containerView, long nativeDrawGLFunctor,
     88             boolean waitForCompletion) {
     89         ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
     90         viewRootImpl.invokeFunctor(nativeDrawGLFunctor, waitForCompletion);
     91     }
     92 
     93     /**
     94      * Calls the function specified with the nativeDrawGLFunctor functor pointer. This
     95      * functionality is used by the WebView for calling into their renderer from the
     96      * framework display lists.
     97      *
     98      * @param canvas a hardware accelerated canvas (see {@link Canvas#isHardwareAccelerated()})
     99      * @param nativeDrawGLFunctor the pointer to the native functor that implements
    100      *        system/core/include/utils/Functor.h
    101      * @throws IllegalArgumentException if the canvas is not hardware accelerated
    102      */
    103     public void callDrawGlFunction(Canvas canvas, long nativeDrawGLFunctor) {
    104         if (!(canvas instanceof DisplayListCanvas)) {
    105             // Canvas#isHardwareAccelerated() is only true for subclasses of HardwareCanvas.
    106             throw new IllegalArgumentException(canvas.getClass().getName()
    107                     + " is not a DisplayList canvas");
    108         }
    109         ((DisplayListCanvas) canvas).callDrawGLFunction2(nativeDrawGLFunctor);
    110     }
    111 
    112     /**
    113      * Detaches the draw GL functor.
    114      *
    115      * @param nativeDrawGLFunctor the pointer to the native functor that implements
    116      *        system/core/include/utils/Functor.h
    117      */
    118     public void detachDrawGlFunctor(View containerView, long nativeDrawGLFunctor) {
    119         ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
    120         if (nativeDrawGLFunctor != 0 && viewRootImpl != null) {
    121             viewRootImpl.detachFunctor(nativeDrawGLFunctor);
    122         }
    123     }
    124 
    125     /**
    126      * Returns the package id of the given {@code packageName}.
    127      */
    128     public int getPackageId(Resources resources, String packageName) {
    129         SparseArray<String> packageIdentifiers =
    130                 resources.getAssets().getAssignedPackageIdentifiers();
    131         for (int i = 0; i < packageIdentifiers.size(); i++) {
    132             final String name = packageIdentifiers.valueAt(i);
    133 
    134             if (packageName.equals(name)) {
    135                 return packageIdentifiers.keyAt(i);
    136             }
    137         }
    138         throw new RuntimeException("Package not found: " + packageName);
    139     }
    140 
    141     /**
    142      * Returns the application which is embedding the WebView.
    143      */
    144     public Application getApplication() {
    145         return ActivityThread.currentApplication();
    146     }
    147 
    148     /**
    149      * Returns the error string for the given {@code errorCode}.
    150      */
    151     public String getErrorString(Context context, int errorCode) {
    152         return LegacyErrorStrings.getString(errorCode, context);
    153     }
    154 
    155     /**
    156      * Adds the WebView asset path to {@link android.content.res.AssetManager}.
    157      */
    158     public void addWebViewAssetPath(Context context) {
    159         context.getAssets().addAssetPath(
    160                 WebViewFactory.getLoadedPackageInfo().applicationInfo.sourceDir);
    161     }
    162 }
    163