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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.app;
     18 
     19 import com.android.internal.R;
     20 import com.android.internal.app.WindowDecorActionBar;
     21 import com.android.internal.policy.PhoneWindow;
     22 
     23 import android.annotation.CallSuper;
     24 import android.annotation.DrawableRes;
     25 import android.annotation.IdRes;
     26 import android.annotation.LayoutRes;
     27 import android.annotation.NonNull;
     28 import android.annotation.Nullable;
     29 import android.annotation.StringRes;
     30 import android.annotation.StyleRes;
     31 import android.content.ComponentName;
     32 import android.content.Context;
     33 import android.content.ContextWrapper;
     34 import android.content.DialogInterface;
     35 import android.content.res.Configuration;
     36 import android.content.pm.ApplicationInfo;
     37 import android.content.res.ResourceId;
     38 import android.graphics.drawable.Drawable;
     39 import android.net.Uri;
     40 import android.os.Bundle;
     41 import android.os.Handler;
     42 import android.os.Looper;
     43 import android.os.Message;
     44 import android.util.Log;
     45 import android.util.TypedValue;
     46 import android.view.ActionMode;
     47 import android.view.ContextMenu;
     48 import android.view.ContextMenu.ContextMenuInfo;
     49 import android.view.ContextThemeWrapper;
     50 import android.view.Gravity;
     51 import android.view.KeyEvent;
     52 import android.view.LayoutInflater;
     53 import android.view.Menu;
     54 import android.view.MenuItem;
     55 import android.view.MotionEvent;
     56 import android.view.SearchEvent;
     57 import android.view.View;
     58 import android.view.View.OnCreateContextMenuListener;
     59 import android.view.ViewGroup;
     60 import android.view.ViewGroup.LayoutParams;
     61 import android.view.Window;
     62 import android.view.WindowManager;
     63 import android.view.accessibility.AccessibilityEvent;
     64 
     65 import java.lang.ref.WeakReference;
     66 
     67 /**
     68  * Base class for Dialogs.
     69  *
     70  * <p>Note: Activities provide a facility to manage the creation, saving and
     71  * restoring of dialogs. See {@link Activity#onCreateDialog(int)},
     72  * {@link Activity#onPrepareDialog(int, Dialog)},
     73  * {@link Activity#showDialog(int)}, and {@link Activity#dismissDialog(int)}. If
     74  * these methods are used, {@link #getOwnerActivity()} will return the Activity
     75  * that managed this dialog.
     76  *
     77  * <p>Often you will want to have a Dialog display on top of the current
     78  * input method, because there is no reason for it to accept text.  You can
     79  * do this by setting the {@link WindowManager.LayoutParams#FLAG_ALT_FOCUSABLE_IM
     80  * WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM} window flag (assuming
     81  * your Dialog takes input focus, as it the default) with the following code:
     82  *
     83  * <pre>
     84  * getWindow().setFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM,
     85  *         WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM);</pre>
     86  *
     87  * <div class="special reference">
     88  * <h3>Developer Guides</h3>
     89  * <p>For more information about creating dialogs, read the
     90  * <a href="{@docRoot}guide/topics/ui/dialogs.html">Dialogs</a> developer guide.</p>
     91  * </div>
     92  */
     93 public class Dialog implements DialogInterface, Window.Callback,
     94         KeyEvent.Callback, OnCreateContextMenuListener, Window.OnWindowDismissedCallback {
     95     private static final String TAG = "Dialog";
     96     private Activity mOwnerActivity;
     97 
     98     private final WindowManager mWindowManager;
     99 
    100     final Context mContext;
    101     final Window mWindow;
    102 
    103     View mDecor;
    104 
    105     private ActionBar mActionBar;
    106     /**
    107      * This field should be made private, so it is hidden from the SDK.
    108      * {@hide}
    109      */
    110     protected boolean mCancelable = true;
    111 
    112     private String mCancelAndDismissTaken;
    113     private Message mCancelMessage;
    114     private Message mDismissMessage;
    115     private Message mShowMessage;
    116 
    117     private OnKeyListener mOnKeyListener;
    118 
    119     private boolean mCreated = false;
    120     private boolean mShowing = false;
    121     private boolean mCanceled = false;
    122 
    123     private final Handler mHandler = new Handler();
    124 
    125     private static final int DISMISS = 0x43;
    126     private static final int CANCEL = 0x44;
    127     private static final int SHOW = 0x45;
    128 
    129     private final Handler mListenersHandler;
    130 
    131     private SearchEvent mSearchEvent;
    132 
    133     private ActionMode mActionMode;
    134 
    135     private int mActionModeTypeStarting = ActionMode.TYPE_PRIMARY;
    136 
    137     private final Runnable mDismissAction = this::dismissDialog;
    138 
    139     /**
    140      * Creates a dialog window that uses the default dialog theme.
    141      * <p>
    142      * The supplied {@code context} is used to obtain the window manager and
    143      * base theme used to present the dialog.
    144      *
    145      * @param context the context in which the dialog should run
    146      * @see android.R.styleable#Theme_dialogTheme
    147      */
    148     public Dialog(@NonNull Context context) {
    149         this(context, 0, true);
    150     }
    151 
    152     /**
    153      * Creates a dialog window that uses a custom dialog style.
    154      * <p>
    155      * The supplied {@code context} is used to obtain the window manager and
    156      * base theme used to present the dialog.
    157      * <p>
    158      * The supplied {@code theme} is applied on top of the context's theme. See
    159      * <a href="{@docRoot}guide/topics/resources/available-resources.html#stylesandthemes">
    160      * Style and Theme Resources</a> for more information about defining and
    161      * using styles.
    162      *
    163      * @param context the context in which the dialog should run
    164      * @param themeResId a style resource describing the theme to use for the
    165      *              window, or {@code 0} to use the default dialog theme
    166      */
    167     public Dialog(@NonNull Context context, @StyleRes int themeResId) {
    168         this(context, themeResId, true);
    169     }
    170 
    171     Dialog(@NonNull Context context, @StyleRes int themeResId, boolean createContextThemeWrapper) {
    172         if (createContextThemeWrapper) {
    173             if (themeResId == ResourceId.ID_NULL) {
    174                 final TypedValue outValue = new TypedValue();
    175                 context.getTheme().resolveAttribute(R.attr.dialogTheme, outValue, true);
    176                 themeResId = outValue.resourceId;
    177             }
    178             mContext = new ContextThemeWrapper(context, themeResId);
    179         } else {
    180             mContext = context;
    181         }
    182 
    183         mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
    184 
    185         final Window w = new PhoneWindow(mContext);
    186         mWindow = w;
    187         w.setCallback(this);
    188         w.setOnWindowDismissedCallback(this);
    189         w.setOnWindowSwipeDismissedCallback(() -> {
    190             if (mCancelable) {
    191                 cancel();
    192             }
    193         });
    194         w.setWindowManager(mWindowManager, null, null);
    195         w.setGravity(Gravity.CENTER);
    196 
    197         mListenersHandler = new ListenersHandler(this);
    198     }
    199 
    200     /**
    201      * @deprecated
    202      * @hide
    203      */
    204     @Deprecated
    205     protected Dialog(@NonNull Context context, boolean cancelable,
    206             @Nullable Message cancelCallback) {
    207         this(context);
    208         mCancelable = cancelable;
    209         updateWindowForCancelable();
    210         mCancelMessage = cancelCallback;
    211     }
    212 
    213     protected Dialog(@NonNull Context context, boolean cancelable,
    214             @Nullable OnCancelListener cancelListener) {
    215         this(context);
    216         mCancelable = cancelable;
    217         updateWindowForCancelable();
    218         setOnCancelListener(cancelListener);
    219     }
    220 
    221     /**
    222      * Retrieve the Context this Dialog is running in.
    223      *
    224      * @return Context The Context used by the Dialog.
    225      */
    226     public final @NonNull Context getContext() {
    227         return mContext;
    228     }
    229 
    230     /**
    231      * Retrieve the {@link ActionBar} attached to this dialog, if present.
    232      *
    233      * @return The ActionBar attached to the dialog or null if no ActionBar is present.
    234      */
    235     public @Nullable ActionBar getActionBar() {
    236         return mActionBar;
    237     }
    238 
    239     /**
    240      * Sets the Activity that owns this dialog. An example use: This Dialog will
    241      * use the suggested volume control stream of the Activity.
    242      *
    243      * @param activity The Activity that owns this dialog.
    244      */
    245     public final void setOwnerActivity(@NonNull Activity activity) {
    246         mOwnerActivity = activity;
    247 
    248         getWindow().setVolumeControlStream(mOwnerActivity.getVolumeControlStream());
    249     }
    250 
    251     /**
    252      * Returns the Activity that owns this Dialog. For example, if
    253      * {@link Activity#showDialog(int)} is used to show this Dialog, that
    254      * Activity will be the owner (by default). Depending on how this dialog was
    255      * created, this may return null.
    256      *
    257      * @return The Activity that owns this Dialog.
    258      */
    259     public final @Nullable Activity getOwnerActivity() {
    260         return mOwnerActivity;
    261     }
    262 
    263     /**
    264      * @return Whether the dialog is currently showing.
    265      */
    266     public boolean isShowing() {
    267         return mShowing;
    268     }
    269 
    270     /**
    271      * Forces immediate creation of the dialog.
    272      * <p>
    273      * Note that you should not override this method to perform dialog creation.
    274      * Rather, override {@link #onCreate(Bundle)}.
    275      */
    276     public void create() {
    277         if (!mCreated) {
    278             dispatchOnCreate(null);
    279         }
    280     }
    281 
    282     /**
    283      * Start the dialog and display it on screen.  The window is placed in the
    284      * application layer and opaque.  Note that you should not override this
    285      * method to do initialization when the dialog is shown, instead implement
    286      * that in {@link #onStart}.
    287      */
    288     public void show() {
    289         if (mShowing) {
    290             if (mDecor != null) {
    291                 if (mWindow.hasFeature(Window.FEATURE_ACTION_BAR)) {
    292                     mWindow.invalidatePanelMenu(Window.FEATURE_ACTION_BAR);
    293                 }
    294                 mDecor.setVisibility(View.VISIBLE);
    295             }
    296             return;
    297         }
    298 
    299         mCanceled = false;
    300 
    301         if (!mCreated) {
    302             dispatchOnCreate(null);
    303         } else {
    304             // Fill the DecorView in on any configuration changes that
    305             // may have occured while it was removed from the WindowManager.
    306             final Configuration config = mContext.getResources().getConfiguration();
    307             mWindow.getDecorView().dispatchConfigurationChanged(config);
    308         }
    309 
    310         onStart();
    311         mDecor = mWindow.getDecorView();
    312 
    313         if (mActionBar == null && mWindow.hasFeature(Window.FEATURE_ACTION_BAR)) {
    314             final ApplicationInfo info = mContext.getApplicationInfo();
    315             mWindow.setDefaultIcon(info.icon);
    316             mWindow.setDefaultLogo(info.logo);
    317             mActionBar = new WindowDecorActionBar(this);
    318         }
    319 
    320         WindowManager.LayoutParams l = mWindow.getAttributes();
    321         if ((l.softInputMode
    322                 & WindowManager.LayoutParams.SOFT_INPUT_IS_FORWARD_NAVIGATION) == 0) {
    323             WindowManager.LayoutParams nl = new WindowManager.LayoutParams();
    324             nl.copyFrom(l);
    325             nl.softInputMode |=
    326                     WindowManager.LayoutParams.SOFT_INPUT_IS_FORWARD_NAVIGATION;
    327             l = nl;
    328         }
    329 
    330         mWindowManager.addView(mDecor, l);
    331         mShowing = true;
    332 
    333         sendShowMessage();
    334     }
    335 
    336     /**
    337      * Hide the dialog, but do not dismiss it.
    338      */
    339     public void hide() {
    340         if (mDecor != null) {
    341             mDecor.setVisibility(View.GONE);
    342         }
    343     }
    344 
    345     /**
    346      * Dismiss this dialog, removing it from the screen. This method can be
    347      * invoked safely from any thread.  Note that you should not override this
    348      * method to do cleanup when the dialog is dismissed, instead implement
    349      * that in {@link #onStop}.
    350      */
    351     @Override
    352     public void dismiss() {
    353         if (Looper.myLooper() == mHandler.getLooper()) {
    354             dismissDialog();
    355         } else {
    356             mHandler.post(mDismissAction);
    357         }
    358     }
    359 
    360     void dismissDialog() {
    361         if (mDecor == null || !mShowing) {
    362             return;
    363         }
    364 
    365         if (mWindow.isDestroyed()) {
    366             Log.e(TAG, "Tried to dismissDialog() but the Dialog's window was already destroyed!");
    367             return;
    368         }
    369 
    370         try {
    371             mWindowManager.removeViewImmediate(mDecor);
    372         } finally {
    373             if (mActionMode != null) {
    374                 mActionMode.finish();
    375             }
    376             mDecor = null;
    377             mWindow.closeAllPanels();
    378             onStop();
    379             mShowing = false;
    380 
    381             sendDismissMessage();
    382         }
    383     }
    384 
    385     private void sendDismissMessage() {
    386         if (mDismissMessage != null) {
    387             // Obtain a new message so this dialog can be re-used
    388             Message.obtain(mDismissMessage).sendToTarget();
    389         }
    390     }
    391 
    392     private void sendShowMessage() {
    393         if (mShowMessage != null) {
    394             // Obtain a new message so this dialog can be re-used
    395             Message.obtain(mShowMessage).sendToTarget();
    396         }
    397     }
    398 
    399     // internal method to make sure mCreated is set properly without requiring
    400     // users to call through to super in onCreate
    401     void dispatchOnCreate(Bundle savedInstanceState) {
    402         if (!mCreated) {
    403             onCreate(savedInstanceState);
    404             mCreated = true;
    405         }
    406     }
    407 
    408     /**
    409      * Similar to {@link Activity#onCreate}, you should initialize your dialog
    410      * in this method, including calling {@link #setContentView}.
    411      * @param savedInstanceState If this dialog is being reinitialized after a
    412      *     the hosting activity was previously shut down, holds the result from
    413      *     the most recent call to {@link #onSaveInstanceState}, or null if this
    414      *     is the first time.
    415      */
    416     protected void onCreate(Bundle savedInstanceState) {
    417     }
    418 
    419     /**
    420      * Called when the dialog is starting.
    421      */
    422     protected void onStart() {
    423         if (mActionBar != null) mActionBar.setShowHideAnimationEnabled(true);
    424     }
    425 
    426     /**
    427      * Called to tell you that you're stopping.
    428      */
    429     protected void onStop() {
    430         if (mActionBar != null) mActionBar.setShowHideAnimationEnabled(false);
    431     }
    432 
    433     private static final String DIALOG_SHOWING_TAG = "android:dialogShowing";
    434     private static final String DIALOG_HIERARCHY_TAG = "android:dialogHierarchy";
    435 
    436     /**
    437      * Saves the state of the dialog into a bundle.
    438      *
    439      * The default implementation saves the state of its view hierarchy, so you'll
    440      * likely want to call through to super if you override this to save additional
    441      * state.
    442      * @return A bundle with the state of the dialog.
    443      */
    444     public @NonNull Bundle onSaveInstanceState() {
    445         Bundle bundle = new Bundle();
    446         bundle.putBoolean(DIALOG_SHOWING_TAG, mShowing);
    447         if (mCreated) {
    448             bundle.putBundle(DIALOG_HIERARCHY_TAG, mWindow.saveHierarchyState());
    449         }
    450         return bundle;
    451     }
    452 
    453     /**
    454      * Restore the state of the dialog from a previously saved bundle.
    455      *
    456      * The default implementation restores the state of the dialog's view
    457      * hierarchy that was saved in the default implementation of {@link #onSaveInstanceState()},
    458      * so be sure to call through to super when overriding unless you want to
    459      * do all restoring of state yourself.
    460      * @param savedInstanceState The state of the dialog previously saved by
    461      *     {@link #onSaveInstanceState()}.
    462      */
    463     public void onRestoreInstanceState(@NonNull Bundle savedInstanceState) {
    464         final Bundle dialogHierarchyState = savedInstanceState.getBundle(DIALOG_HIERARCHY_TAG);
    465         if (dialogHierarchyState == null) {
    466             // dialog has never been shown, or onCreated, nothing to restore.
    467             return;
    468         }
    469         dispatchOnCreate(savedInstanceState);
    470         mWindow.restoreHierarchyState(dialogHierarchyState);
    471         if (savedInstanceState.getBoolean(DIALOG_SHOWING_TAG)) {
    472             show();
    473         }
    474     }
    475 
    476     /**
    477      * Retrieve the current Window for the activity.  This can be used to
    478      * directly access parts of the Window API that are not available
    479      * through Activity/Screen.
    480      *
    481      * @return Window The current window, or null if the activity is not
    482      *         visual.
    483      */
    484     public @Nullable Window getWindow() {
    485         return mWindow;
    486     }
    487 
    488     /**
    489      * Call {@link android.view.Window#getCurrentFocus} on the
    490      * Window if this Activity to return the currently focused view.
    491      *
    492      * @return View The current View with focus or null.
    493      *
    494      * @see #getWindow
    495      * @see android.view.Window#getCurrentFocus
    496      */
    497     public @Nullable View getCurrentFocus() {
    498         return mWindow != null ? mWindow.getCurrentFocus() : null;
    499     }
    500 
    501     /**
    502      * Finds the first descendant view with the given ID or {@code null} if the
    503      * ID is invalid (< 0), there is no matching view in the hierarchy, or the
    504      * dialog has not yet been fully created (for example, via {@link #show()}
    505      * or {@link #create()}).
    506      * <p>
    507      * <strong>Note:</strong> In most cases -- depending on compiler support --
    508      * the resulting view is automatically cast to the target class type. If
    509      * the target class type is unconstrained, an explicit cast may be
    510      * necessary.
    511      *
    512      * @param id the ID to search for
    513      * @return a view with given ID if found, or {@code null} otherwise
    514      * @see View#findViewById(int)
    515      */
    516     @Nullable
    517     public <T extends View> T findViewById(@IdRes int id) {
    518         return mWindow.findViewById(id);
    519     }
    520 
    521     /**
    522      * Set the screen content from a layout resource.  The resource will be
    523      * inflated, adding all top-level views to the screen.
    524      *
    525      * @param layoutResID Resource ID to be inflated.
    526      */
    527     public void setContentView(@LayoutRes int layoutResID) {
    528         mWindow.setContentView(layoutResID);
    529     }
    530 
    531     /**
    532      * Set the screen content to an explicit view.  This view is placed
    533      * directly into the screen's view hierarchy.  It can itself be a complex
    534      * view hierarchy.
    535      *
    536      * @param view The desired content to display.
    537      */
    538     public void setContentView(@NonNull View view) {
    539         mWindow.setContentView(view);
    540     }
    541 
    542     /**
    543      * Set the screen content to an explicit view.  This view is placed
    544      * directly into the screen's view hierarchy.  It can itself be a complex
    545      * view hierarchy.
    546      *
    547      * @param view The desired content to display.
    548      * @param params Layout parameters for the view.
    549      */
    550     public void setContentView(@NonNull View view, @Nullable ViewGroup.LayoutParams params) {
    551         mWindow.setContentView(view, params);
    552     }
    553 
    554     /**
    555      * Add an additional content view to the screen.  Added after any existing
    556      * ones in the screen -- existing views are NOT removed.
    557      *
    558      * @param view The desired content to display.
    559      * @param params Layout parameters for the view.
    560      */
    561     public void addContentView(@NonNull View view, @Nullable ViewGroup.LayoutParams params) {
    562         mWindow.addContentView(view, params);
    563     }
    564 
    565     /**
    566      * Set the title text for this dialog's window.
    567      *
    568      * @param title The new text to display in the title.
    569      */
    570     public void setTitle(@Nullable CharSequence title) {
    571         mWindow.setTitle(title);
    572         mWindow.getAttributes().setTitle(title);
    573     }
    574 
    575     /**
    576      * Set the title text for this dialog's window. The text is retrieved
    577      * from the resources with the supplied identifier.
    578      *
    579      * @param titleId the title's text resource identifier
    580      */
    581     public void setTitle(@StringRes int titleId) {
    582         setTitle(mContext.getText(titleId));
    583     }
    584 
    585     /**
    586      * A key was pressed down.
    587      *
    588      * <p>If the focused view didn't want this event, this method is called.
    589      *
    590      * <p>The default implementation consumed the KEYCODE_BACK to later
    591      * handle it in {@link #onKeyUp}.
    592      *
    593      * @see #onKeyUp
    594      * @see android.view.KeyEvent
    595      */
    596     @Override
    597     public boolean onKeyDown(int keyCode, @NonNull KeyEvent event) {
    598         if (keyCode == KeyEvent.KEYCODE_BACK) {
    599             event.startTracking();
    600             return true;
    601         }
    602 
    603         return false;
    604     }
    605 
    606     /**
    607      * Default implementation of {@link KeyEvent.Callback#onKeyLongPress(int, KeyEvent)
    608      * KeyEvent.Callback.onKeyLongPress()}: always returns false (doesn't handle
    609      * the event).
    610      */
    611     @Override
    612     public boolean onKeyLongPress(int keyCode, @NonNull KeyEvent event) {
    613         return false;
    614     }
    615 
    616     /**
    617      * A key was released.
    618      *
    619      * <p>The default implementation handles KEYCODE_BACK to close the
    620      * dialog.
    621      *
    622      * @see #onKeyDown
    623      * @see KeyEvent
    624      */
    625     @Override
    626     public boolean onKeyUp(int keyCode, @NonNull KeyEvent event) {
    627         if (keyCode == KeyEvent.KEYCODE_BACK && event.isTracking()
    628                 && !event.isCanceled()) {
    629             onBackPressed();
    630             return true;
    631         }
    632         return false;
    633     }
    634 
    635     /**
    636      * Default implementation of {@link KeyEvent.Callback#onKeyMultiple(int, int, KeyEvent)
    637      * KeyEvent.Callback.onKeyMultiple()}: always returns false (doesn't handle
    638      * the event).
    639      */
    640     @Override
    641     public boolean onKeyMultiple(int keyCode, int repeatCount, @NonNull KeyEvent event) {
    642         return false;
    643     }
    644 
    645     /**
    646      * Called when the dialog has detected the user's press of the back
    647      * key.  The default implementation simply cancels the dialog (only if
    648      * it is cancelable), but you can override this to do whatever you want.
    649      */
    650     public void onBackPressed() {
    651         if (mCancelable) {
    652             cancel();
    653         }
    654     }
    655 
    656     /**
    657      * Called when a key shortcut event is not handled by any of the views in the Dialog.
    658      * Override this method to implement global key shortcuts for the Dialog.
    659      * Key shortcuts can also be implemented by setting the
    660      * {@link MenuItem#setShortcut(char, char) shortcut} property of menu items.
    661      *
    662      * @param keyCode The value in event.getKeyCode().
    663      * @param event Description of the key event.
    664      * @return True if the key shortcut was handled.
    665      */
    666     public boolean onKeyShortcut(int keyCode, @NonNull KeyEvent event) {
    667         return false;
    668     }
    669 
    670     /**
    671      * Called when a touch screen event was not handled by any of the views
    672      * under it. This is most useful to process touch events that happen outside
    673      * of your window bounds, where there is no view to receive it.
    674      *
    675      * @param event The touch screen event being processed.
    676      * @return Return true if you have consumed the event, false if you haven't.
    677      *         The default implementation will cancel the dialog when a touch
    678      *         happens outside of the window bounds.
    679      */
    680     public boolean onTouchEvent(@NonNull MotionEvent event) {
    681         if (mCancelable && mShowing && mWindow.shouldCloseOnTouch(mContext, event)) {
    682             cancel();
    683             return true;
    684         }
    685 
    686         return false;
    687     }
    688 
    689     /**
    690      * Called when the trackball was moved and not handled by any of the
    691      * views inside of the activity.  So, for example, if the trackball moves
    692      * while focus is on a button, you will receive a call here because
    693      * buttons do not normally do anything with trackball events.  The call
    694      * here happens <em>before</em> trackball movements are converted to
    695      * DPAD key events, which then get sent back to the view hierarchy, and
    696      * will be processed at the point for things like focus navigation.
    697      *
    698      * @param event The trackball event being processed.
    699      *
    700      * @return Return true if you have consumed the event, false if you haven't.
    701      * The default implementation always returns false.
    702      */
    703     public boolean onTrackballEvent(@NonNull MotionEvent event) {
    704         return false;
    705     }
    706 
    707     /**
    708      * Called when a generic motion event was not handled by any of the
    709      * views inside of the dialog.
    710      * <p>
    711      * Generic motion events describe joystick movements, mouse hovers, track pad
    712      * touches, scroll wheel movements and other input events.  The
    713      * {@link MotionEvent#getSource() source} of the motion event specifies
    714      * the class of input that was received.  Implementations of this method
    715      * must examine the bits in the source before processing the event.
    716      * The following code example shows how this is done.
    717      * </p><p>
    718      * Generic motion events with source class
    719      * {@link android.view.InputDevice#SOURCE_CLASS_POINTER}
    720      * are delivered to the view under the pointer.  All other generic motion events are
    721      * delivered to the focused view.
    722      * </p><p>
    723      * See {@link View#onGenericMotionEvent(MotionEvent)} for an example of how to
    724      * handle this event.
    725      * </p>
    726      *
    727      * @param event The generic motion event being processed.
    728      *
    729      * @return Return true if you have consumed the event, false if you haven't.
    730      * The default implementation always returns false.
    731      */
    732     public boolean onGenericMotionEvent(@NonNull MotionEvent event) {
    733         return false;
    734     }
    735 
    736     @Override
    737     public void onWindowAttributesChanged(WindowManager.LayoutParams params) {
    738         if (mDecor != null) {
    739             mWindowManager.updateViewLayout(mDecor, params);
    740         }
    741     }
    742 
    743     @Override
    744     public void onContentChanged() {
    745     }
    746 
    747     @Override
    748     public void onWindowFocusChanged(boolean hasFocus) {
    749     }
    750 
    751     @Override
    752     public void onAttachedToWindow() {
    753     }
    754 
    755     @Override
    756     public void onDetachedFromWindow() {
    757     }
    758 
    759     /** @hide */
    760     @Override
    761     public void onWindowDismissed(boolean finishTask, boolean suppressWindowTransition) {
    762         dismiss();
    763     }
    764 
    765     /**
    766      * Called to process key events.  You can override this to intercept all
    767      * key events before they are dispatched to the window.  Be sure to call
    768      * this implementation for key events that should be handled normally.
    769      *
    770      * @param event The key event.
    771      *
    772      * @return boolean Return true if this event was consumed.
    773      */
    774     @Override
    775     public boolean dispatchKeyEvent(@NonNull KeyEvent event) {
    776         if ((mOnKeyListener != null) && (mOnKeyListener.onKey(this, event.getKeyCode(), event))) {
    777             return true;
    778         }
    779         if (mWindow.superDispatchKeyEvent(event)) {
    780             return true;
    781         }
    782         return event.dispatch(this, mDecor != null
    783                 ? mDecor.getKeyDispatcherState() : null, this);
    784     }
    785 
    786     /**
    787      * Called to process a key shortcut event.
    788      * You can override this to intercept all key shortcut events before they are
    789      * dispatched to the window.  Be sure to call this implementation for key shortcut
    790      * events that should be handled normally.
    791      *
    792      * @param event The key shortcut event.
    793      * @return True if this event was consumed.
    794      */
    795     @Override
    796     public boolean dispatchKeyShortcutEvent(@NonNull KeyEvent event) {
    797         if (mWindow.superDispatchKeyShortcutEvent(event)) {
    798             return true;
    799         }
    800         return onKeyShortcut(event.getKeyCode(), event);
    801     }
    802 
    803     /**
    804      * Called to process touch screen events.  You can override this to
    805      * intercept all touch screen events before they are dispatched to the
    806      * window.  Be sure to call this implementation for touch screen events
    807      * that should be handled normally.
    808      *
    809      * @param ev The touch screen event.
    810      *
    811      * @return boolean Return true if this event was consumed.
    812      */
    813     @Override
    814     public boolean dispatchTouchEvent(@NonNull MotionEvent ev) {
    815         if (mWindow.superDispatchTouchEvent(ev)) {
    816             return true;
    817         }
    818         return onTouchEvent(ev);
    819     }
    820 
    821     /**
    822      * Called to process trackball events.  You can override this to
    823      * intercept all trackball events before they are dispatched to the
    824      * window.  Be sure to call this implementation for trackball events
    825      * that should be handled normally.
    826      *
    827      * @param ev The trackball event.
    828      *
    829      * @return boolean Return true if this event was consumed.
    830      */
    831     @Override
    832     public boolean dispatchTrackballEvent(@NonNull MotionEvent ev) {
    833         if (mWindow.superDispatchTrackballEvent(ev)) {
    834             return true;
    835         }
    836         return onTrackballEvent(ev);
    837     }
    838 
    839     /**
    840      * Called to process generic motion events.  You can override this to
    841      * intercept all generic motion events before they are dispatched to the
    842      * window.  Be sure to call this implementation for generic motion events
    843      * that should be handled normally.
    844      *
    845      * @param ev The generic motion event.
    846      *
    847      * @return boolean Return true if this event was consumed.
    848      */
    849     @Override
    850     public boolean dispatchGenericMotionEvent(@NonNull MotionEvent ev) {
    851         if (mWindow.superDispatchGenericMotionEvent(ev)) {
    852             return true;
    853         }
    854         return onGenericMotionEvent(ev);
    855     }
    856 
    857     @Override
    858     public boolean dispatchPopulateAccessibilityEvent(@NonNull AccessibilityEvent event) {
    859         event.setClassName(getClass().getName());
    860         event.setPackageName(mContext.getPackageName());
    861 
    862         LayoutParams params = getWindow().getAttributes();
    863         boolean isFullScreen = (params.width == LayoutParams.MATCH_PARENT) &&
    864             (params.height == LayoutParams.MATCH_PARENT);
    865         event.setFullScreen(isFullScreen);
    866 
    867         return false;
    868     }
    869 
    870     /**
    871      * @see Activity#onCreatePanelView(int)
    872      */
    873     @Override
    874     public View onCreatePanelView(int featureId) {
    875         return null;
    876     }
    877 
    878     /**
    879      * @see Activity#onCreatePanelMenu(int, Menu)
    880      */
    881     @Override
    882     public boolean onCreatePanelMenu(int featureId, @NonNull Menu menu) {
    883         if (featureId == Window.FEATURE_OPTIONS_PANEL) {
    884             return onCreateOptionsMenu(menu);
    885         }
    886 
    887         return false;
    888     }
    889 
    890     /**
    891      * @see Activity#onPreparePanel(int, View, Menu)
    892      */
    893     @Override
    894     public boolean onPreparePanel(int featureId, View view, Menu menu) {
    895         if (featureId == Window.FEATURE_OPTIONS_PANEL && menu != null) {
    896             return onPrepareOptionsMenu(menu) && menu.hasVisibleItems();
    897         }
    898         return true;
    899     }
    900 
    901     /**
    902      * @see Activity#onMenuOpened(int, Menu)
    903      */
    904     @Override
    905     public boolean onMenuOpened(int featureId, Menu menu) {
    906         if (featureId == Window.FEATURE_ACTION_BAR) {
    907             mActionBar.dispatchMenuVisibilityChanged(true);
    908         }
    909         return true;
    910     }
    911 
    912     /**
    913      * @see Activity#onMenuItemSelected(int, MenuItem)
    914      */
    915     @Override
    916     public boolean onMenuItemSelected(int featureId, MenuItem item) {
    917         return false;
    918     }
    919 
    920     /**
    921      * @see Activity#onPanelClosed(int, Menu)
    922      */
    923     @Override
    924     public void onPanelClosed(int featureId, Menu menu) {
    925         if (featureId == Window.FEATURE_ACTION_BAR) {
    926             mActionBar.dispatchMenuVisibilityChanged(false);
    927         }
    928     }
    929 
    930     /**
    931      * It is usually safe to proxy this call to the owner activity's
    932      * {@link Activity#onCreateOptionsMenu(Menu)} if the client desires the same
    933      * menu for this Dialog.
    934      *
    935      * @see Activity#onCreateOptionsMenu(Menu)
    936      * @see #getOwnerActivity()
    937      */
    938     public boolean onCreateOptionsMenu(@NonNull Menu menu) {
    939         return true;
    940     }
    941 
    942     /**
    943      * It is usually safe to proxy this call to the owner activity's
    944      * {@link Activity#onPrepareOptionsMenu(Menu)} if the client desires the
    945      * same menu for this Dialog.
    946      *
    947      * @see Activity#onPrepareOptionsMenu(Menu)
    948      * @see #getOwnerActivity()
    949      */
    950     public boolean onPrepareOptionsMenu(@NonNull Menu menu) {
    951         return true;
    952     }
    953 
    954     /**
    955      * @see Activity#onOptionsItemSelected(MenuItem)
    956      */
    957     public boolean onOptionsItemSelected(@NonNull MenuItem item) {
    958         return false;
    959     }
    960 
    961     /**
    962      * @see Activity#onOptionsMenuClosed(Menu)
    963      */
    964     public void onOptionsMenuClosed(@NonNull Menu menu) {
    965     }
    966 
    967     /**
    968      * @see Activity#openOptionsMenu()
    969      */
    970     public void openOptionsMenu() {
    971         if (mWindow.hasFeature(Window.FEATURE_OPTIONS_PANEL)) {
    972             mWindow.openPanel(Window.FEATURE_OPTIONS_PANEL, null);
    973         }
    974     }
    975 
    976     /**
    977      * @see Activity#closeOptionsMenu()
    978      */
    979     public void closeOptionsMenu() {
    980         if (mWindow.hasFeature(Window.FEATURE_OPTIONS_PANEL)) {
    981             mWindow.closePanel(Window.FEATURE_OPTIONS_PANEL);
    982         }
    983     }
    984 
    985     /**
    986      * @see Activity#invalidateOptionsMenu()
    987      */
    988     public void invalidateOptionsMenu() {
    989         if (mWindow.hasFeature(Window.FEATURE_OPTIONS_PANEL)) {
    990             mWindow.invalidatePanelMenu(Window.FEATURE_OPTIONS_PANEL);
    991         }
    992     }
    993 
    994     /**
    995      * @see Activity#onCreateContextMenu(ContextMenu, View, ContextMenuInfo)
    996      */
    997     @Override
    998     public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
    999     }
   1000 
   1001     /**
   1002      * @see Activity#registerForContextMenu(View)
   1003      */
   1004     public void registerForContextMenu(@NonNull View view) {
   1005         view.setOnCreateContextMenuListener(this);
   1006     }
   1007 
   1008     /**
   1009      * @see Activity#unregisterForContextMenu(View)
   1010      */
   1011     public void unregisterForContextMenu(@NonNull View view) {
   1012         view.setOnCreateContextMenuListener(null);
   1013     }
   1014 
   1015     /**
   1016      * @see Activity#openContextMenu(View)
   1017      */
   1018     public void openContextMenu(@NonNull View view) {
   1019         view.showContextMenu();
   1020     }
   1021 
   1022     /**
   1023      * @see Activity#onContextItemSelected(MenuItem)
   1024      */
   1025     public boolean onContextItemSelected(@NonNull MenuItem item) {
   1026         return false;
   1027     }
   1028 
   1029     /**
   1030      * @see Activity#onContextMenuClosed(Menu)
   1031      */
   1032     public void onContextMenuClosed(@NonNull Menu menu) {
   1033     }
   1034 
   1035     /**
   1036      * This hook is called when the user signals the desire to start a search.
   1037      */
   1038     @Override
   1039     public boolean onSearchRequested(@NonNull SearchEvent searchEvent) {
   1040         mSearchEvent = searchEvent;
   1041         return onSearchRequested();
   1042     }
   1043 
   1044     /**
   1045      * This hook is called when the user signals the desire to start a search.
   1046      */
   1047     @Override
   1048     public boolean onSearchRequested() {
   1049         final SearchManager searchManager = (SearchManager) mContext
   1050                 .getSystemService(Context.SEARCH_SERVICE);
   1051 
   1052         // associate search with owner activity
   1053         final ComponentName appName = getAssociatedActivity();
   1054         if (appName != null && searchManager.getSearchableInfo(appName) != null) {
   1055             searchManager.startSearch(null, false, appName, null, false);
   1056             dismiss();
   1057             return true;
   1058         } else {
   1059             return false;
   1060         }
   1061     }
   1062 
   1063     /**
   1064      * During the onSearchRequested() callbacks, this function will return the
   1065      * {@link SearchEvent} that triggered the callback, if it exists.
   1066      *
   1067      * @return SearchEvent The SearchEvent that triggered the {@link
   1068      *                    #onSearchRequested} callback.
   1069      */
   1070     public final @Nullable SearchEvent getSearchEvent() {
   1071         return mSearchEvent;
   1072     }
   1073 
   1074     @Override
   1075     public ActionMode onWindowStartingActionMode(ActionMode.Callback callback) {
   1076         if (mActionBar != null && mActionModeTypeStarting == ActionMode.TYPE_PRIMARY) {
   1077             return mActionBar.startActionMode(callback);
   1078         }
   1079         return null;
   1080     }
   1081 
   1082     @Override
   1083     public ActionMode onWindowStartingActionMode(ActionMode.Callback callback, int type) {
   1084         try {
   1085             mActionModeTypeStarting = type;
   1086             return onWindowStartingActionMode(callback);
   1087         } finally {
   1088             mActionModeTypeStarting = ActionMode.TYPE_PRIMARY;
   1089         }
   1090     }
   1091 
   1092     /**
   1093      * {@inheritDoc}
   1094      *
   1095      * Note that if you override this method you should always call through
   1096      * to the superclass implementation by calling super.onActionModeStarted(mode).
   1097      */
   1098     @Override
   1099     @CallSuper
   1100     public void onActionModeStarted(ActionMode mode) {
   1101         mActionMode = mode;
   1102     }
   1103 
   1104     /**
   1105      * {@inheritDoc}
   1106      *
   1107      * Note that if you override this method you should always call through
   1108      * to the superclass implementation by calling super.onActionModeFinished(mode).
   1109      */
   1110     @Override
   1111     @CallSuper
   1112     public void onActionModeFinished(ActionMode mode) {
   1113         if (mode == mActionMode) {
   1114             mActionMode = null;
   1115         }
   1116     }
   1117 
   1118     /**
   1119      * @return The activity associated with this dialog, or null if there is no associated activity.
   1120      */
   1121     private ComponentName getAssociatedActivity() {
   1122         Activity activity = mOwnerActivity;
   1123         Context context = getContext();
   1124         while (activity == null && context != null) {
   1125             if (context instanceof Activity) {
   1126                 activity = (Activity) context;  // found it!
   1127             } else {
   1128                 context = (context instanceof ContextWrapper) ?
   1129                         ((ContextWrapper) context).getBaseContext() : // unwrap one level
   1130                         null;                                         // done
   1131             }
   1132         }
   1133         return activity == null ? null : activity.getComponentName();
   1134     }
   1135 
   1136 
   1137     /**
   1138      * Request that key events come to this dialog. Use this if your
   1139      * dialog has no views with focus, but the dialog still wants
   1140      * a chance to process key events.
   1141      *
   1142      * @param get true if the dialog should receive key events, false otherwise
   1143      * @see android.view.Window#takeKeyEvents
   1144      */
   1145     public void takeKeyEvents(boolean get) {
   1146         mWindow.takeKeyEvents(get);
   1147     }
   1148 
   1149     /**
   1150      * Enable extended window features.  This is a convenience for calling
   1151      * {@link android.view.Window#requestFeature getWindow().requestFeature()}.
   1152      *
   1153      * @param featureId The desired feature as defined in
   1154      *                  {@link android.view.Window}.
   1155      * @return Returns true if the requested feature is supported and now
   1156      *         enabled.
   1157      *
   1158      * @see android.view.Window#requestFeature
   1159      */
   1160     public final boolean requestWindowFeature(int featureId) {
   1161         return getWindow().requestFeature(featureId);
   1162     }
   1163 
   1164     /**
   1165      * Convenience for calling
   1166      * {@link android.view.Window#setFeatureDrawableResource}.
   1167      */
   1168     public final void setFeatureDrawableResource(int featureId, @DrawableRes int resId) {
   1169         getWindow().setFeatureDrawableResource(featureId, resId);
   1170     }
   1171 
   1172     /**
   1173      * Convenience for calling
   1174      * {@link android.view.Window#setFeatureDrawableUri}.
   1175      */
   1176     public final void setFeatureDrawableUri(int featureId, @Nullable Uri uri) {
   1177         getWindow().setFeatureDrawableUri(featureId, uri);
   1178     }
   1179 
   1180     /**
   1181      * Convenience for calling
   1182      * {@link android.view.Window#setFeatureDrawable(int, Drawable)}.
   1183      */
   1184     public final void setFeatureDrawable(int featureId, @Nullable Drawable drawable) {
   1185         getWindow().setFeatureDrawable(featureId, drawable);
   1186     }
   1187 
   1188     /**
   1189      * Convenience for calling
   1190      * {@link android.view.Window#setFeatureDrawableAlpha}.
   1191      */
   1192     public final void setFeatureDrawableAlpha(int featureId, int alpha) {
   1193         getWindow().setFeatureDrawableAlpha(featureId, alpha);
   1194     }
   1195 
   1196     public @NonNull LayoutInflater getLayoutInflater() {
   1197         return getWindow().getLayoutInflater();
   1198     }
   1199 
   1200     /**
   1201      * Sets whether this dialog is cancelable with the
   1202      * {@link KeyEvent#KEYCODE_BACK BACK} key.
   1203      */
   1204     public void setCancelable(boolean flag) {
   1205         mCancelable = flag;
   1206         updateWindowForCancelable();
   1207     }
   1208 
   1209     /**
   1210      * Sets whether this dialog is canceled when touched outside the window's
   1211      * bounds. If setting to true, the dialog is set to be cancelable if not
   1212      * already set.
   1213      *
   1214      * @param cancel Whether the dialog should be canceled when touched outside
   1215      *            the window.
   1216      */
   1217     public void setCanceledOnTouchOutside(boolean cancel) {
   1218         if (cancel && !mCancelable) {
   1219             mCancelable = true;
   1220             updateWindowForCancelable();
   1221         }
   1222 
   1223         mWindow.setCloseOnTouchOutside(cancel);
   1224     }
   1225 
   1226     /**
   1227      * Cancel the dialog.  This is essentially the same as calling {@link #dismiss()}, but it will
   1228      * also call your {@link DialogInterface.OnCancelListener} (if registered).
   1229      */
   1230     @Override
   1231     public void cancel() {
   1232         if (!mCanceled && mCancelMessage != null) {
   1233             mCanceled = true;
   1234             // Obtain a new message so this dialog can be re-used
   1235             Message.obtain(mCancelMessage).sendToTarget();
   1236         }
   1237         dismiss();
   1238     }
   1239 
   1240     /**
   1241      * Set a listener to be invoked when the dialog is canceled.
   1242      *
   1243      * <p>This will only be invoked when the dialog is canceled.
   1244      * Cancel events alone will not capture all ways that
   1245      * the dialog might be dismissed. If the creator needs
   1246      * to know when a dialog is dismissed in general, use
   1247      * {@link #setOnDismissListener}.</p>
   1248      *
   1249      * @param listener The {@link DialogInterface.OnCancelListener} to use.
   1250      */
   1251     public void setOnCancelListener(@Nullable OnCancelListener listener) {
   1252         if (mCancelAndDismissTaken != null) {
   1253             throw new IllegalStateException(
   1254                     "OnCancelListener is already taken by "
   1255                     + mCancelAndDismissTaken + " and can not be replaced.");
   1256         }
   1257         if (listener != null) {
   1258             mCancelMessage = mListenersHandler.obtainMessage(CANCEL, listener);
   1259         } else {
   1260             mCancelMessage = null;
   1261         }
   1262     }
   1263 
   1264     /**
   1265      * Set a message to be sent when the dialog is canceled.
   1266      * @param msg The msg to send when the dialog is canceled.
   1267      * @see #setOnCancelListener(android.content.DialogInterface.OnCancelListener)
   1268      */
   1269     public void setCancelMessage(@Nullable Message msg) {
   1270         mCancelMessage = msg;
   1271     }
   1272 
   1273     /**
   1274      * Set a listener to be invoked when the dialog is dismissed.
   1275      * @param listener The {@link DialogInterface.OnDismissListener} to use.
   1276      */
   1277     public void setOnDismissListener(@Nullable OnDismissListener listener) {
   1278         if (mCancelAndDismissTaken != null) {
   1279             throw new IllegalStateException(
   1280                     "OnDismissListener is already taken by "
   1281                     + mCancelAndDismissTaken + " and can not be replaced.");
   1282         }
   1283         if (listener != null) {
   1284             mDismissMessage = mListenersHandler.obtainMessage(DISMISS, listener);
   1285         } else {
   1286             mDismissMessage = null;
   1287         }
   1288     }
   1289 
   1290     /**
   1291      * Sets a listener to be invoked when the dialog is shown.
   1292      * @param listener The {@link DialogInterface.OnShowListener} to use.
   1293      */
   1294     public void setOnShowListener(@Nullable OnShowListener listener) {
   1295         if (listener != null) {
   1296             mShowMessage = mListenersHandler.obtainMessage(SHOW, listener);
   1297         } else {
   1298             mShowMessage = null;
   1299         }
   1300     }
   1301 
   1302     /**
   1303      * Set a message to be sent when the dialog is dismissed.
   1304      * @param msg The msg to send when the dialog is dismissed.
   1305      */
   1306     public void setDismissMessage(@Nullable Message msg) {
   1307         mDismissMessage = msg;
   1308     }
   1309 
   1310     /** @hide */
   1311     public boolean takeCancelAndDismissListeners(@Nullable String msg,
   1312             @Nullable OnCancelListener cancel, @Nullable OnDismissListener dismiss) {
   1313         if (mCancelAndDismissTaken != null) {
   1314             mCancelAndDismissTaken = null;
   1315         } else if (mCancelMessage != null || mDismissMessage != null) {
   1316             return false;
   1317         }
   1318 
   1319         setOnCancelListener(cancel);
   1320         setOnDismissListener(dismiss);
   1321         mCancelAndDismissTaken = msg;
   1322 
   1323         return true;
   1324     }
   1325 
   1326     /**
   1327      * By default, this will use the owner Activity's suggested stream type.
   1328      *
   1329      * @see Activity#setVolumeControlStream(int)
   1330      * @see #setOwnerActivity(Activity)
   1331      */
   1332     public final void setVolumeControlStream(int streamType) {
   1333         getWindow().setVolumeControlStream(streamType);
   1334     }
   1335 
   1336     /**
   1337      * @see Activity#getVolumeControlStream()
   1338      */
   1339     public final int getVolumeControlStream() {
   1340         return getWindow().getVolumeControlStream();
   1341     }
   1342 
   1343     /**
   1344      * Sets the callback that will be called if a key is dispatched to the dialog.
   1345      */
   1346     public void setOnKeyListener(@Nullable OnKeyListener onKeyListener) {
   1347         mOnKeyListener = onKeyListener;
   1348     }
   1349 
   1350     private static final class ListenersHandler extends Handler {
   1351         private final WeakReference<DialogInterface> mDialog;
   1352 
   1353         public ListenersHandler(Dialog dialog) {
   1354             mDialog = new WeakReference<>(dialog);
   1355         }
   1356 
   1357         @Override
   1358         public void handleMessage(Message msg) {
   1359             switch (msg.what) {
   1360                 case DISMISS:
   1361                     ((OnDismissListener) msg.obj).onDismiss(mDialog.get());
   1362                     break;
   1363                 case CANCEL:
   1364                     ((OnCancelListener) msg.obj).onCancel(mDialog.get());
   1365                     break;
   1366                 case SHOW:
   1367                     ((OnShowListener) msg.obj).onShow(mDialog.get());
   1368                     break;
   1369             }
   1370         }
   1371     }
   1372 
   1373     private void updateWindowForCancelable() {
   1374         mWindow.setCloseOnSwipeEnabled(mCancelable);
   1375     }
   1376 }
   1377