packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2014 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.systemui.recents;

 import android.app.Activity;
 import android.app.ActivityOptions;
 import android.app.SearchManager;
 import android.appwidget.AppWidgetHostView;
 import android.appwidget.AppWidgetManager;
 import android.appwidget.AppWidgetProviderInfo;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.os.UserHandle;
 import android.util.Pair;
 import android.view.KeyEvent;
 import android.view.View;
 import android.view.ViewStub;
 import android.widget.Toast;
 import com.android.systemui.R;
 import com.android.systemui.recents.misc.Console;
 import com.android.systemui.recents.misc.DebugTrigger;
 import com.android.systemui.recents.misc.ReferenceCountedTrigger;
 import com.android.systemui.recents.misc.SystemServicesProxy;
 import com.android.systemui.recents.misc.Utilities;
 import com.android.systemui.recents.model.RecentsTaskLoader;
 import com.android.systemui.recents.model.SpaceNode;
 import com.android.systemui.recents.model.TaskStack;
 import com.android.systemui.recents.views.FullscreenTransitionOverlayView;
 import com.android.systemui.recents.views.RecentsView;
 import com.android.systemui.recents.views.SystemBarScrimViews;
 import com.android.systemui.recents.views.ViewAnimation;

 import java.lang.ref.WeakReference;
 import java.lang.reflect.InvocationTargetException;
 import java.util.ArrayList;

 /**
  * The main Recents activity that is started from AlternateRecentsComponent.
  */
 public class RecentsActivity extends Activity implements RecentsView.RecentsViewCallbacks,
         RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks,
         FullscreenTransitionOverlayView.FullScreenTransitionViewCallbacks {

     // Actions and Extras sent from AlternateRecentsComponent
     final static String EXTRA_TRIGGERED_FROM_ALT_TAB = "extra_triggered_from_alt_tab";
     final static String ACTION_START_ENTER_ANIMATION = "action_start_enter_animation";
     final static String ACTION_TOGGLE_RECENTS_ACTIVITY = "action_toggle_recents_activity";
     final static String ACTION_HIDE_RECENTS_ACTIVITY = "action_hide_recents_activity";

     RecentsConfiguration mConfig;
     boolean mVisible;

     // Top level views
     RecentsView mRecentsView;
     SystemBarScrimViews mScrimViews;
     ViewStub mEmptyViewStub;
     View mEmptyView;
     ViewStub mFullscreenOverlayStub;
     FullscreenTransitionOverlayView mFullScreenOverlayView;

     // Search AppWidget
     RecentsAppWidgetHost mAppWidgetHost;
     AppWidgetProviderInfo mSearchAppWidgetInfo;
     AppWidgetHostView mSearchAppWidgetHostView;


     // Runnables to finish the Recents activity
     FinishRecentsRunnable mFinishRunnable = new FinishRecentsRunnable();
     FinishRecentsRunnable mFinishLaunchHomeRunnable;

     /**
      * A common Runnable to finish Recents either by calling finish() (with a custom animation) or
      * launching Home with some ActivityOptions.  Generally we always launch home when we exit
      * Recents rather than just finishing the activity since we don't know what is behind Recents in
      * the task stack.  The only case where we finish() directly is when we are cancelling the full
      * screen transition from the app.
      */
     class FinishRecentsRunnable implements Runnable {
         Intent mLaunchIntent;
         ActivityOptions mLaunchOpts;

         public FinishRecentsRunnable() {
             // Do nothing
         }

         /**
          * Creates a finish runnable that starts the specified intent, using the given
          * ActivityOptions.
          */
         public FinishRecentsRunnable(Intent launchIntent, ActivityOptions opts) {
             mLaunchIntent = launchIntent;
             mLaunchOpts = opts;
         }

         @Override
         public void run() {
             // Mark Recents as no longer visible
             AlternateRecentsComponent.notifyVisibilityChanged(false);
             mVisible = false;
             // Finish Recents
             if (mLaunchIntent != null) {
                 if (mLaunchOpts != null) {
                     startActivityAsUser(mLaunchIntent, UserHandle.CURRENT);
                 } else {
                     startActivityAsUser(mLaunchIntent, mLaunchOpts.toBundle(), UserHandle.CURRENT);
                 }
             } else {
                 finish();
                 overridePendingTransition(R.anim.recents_to_launcher_enter,
                         R.anim.recents_to_launcher_exit);
             }
         }
     }

     /**
      * Broadcast receiver to handle messages from AlternateRecentsComponent.
      */
     final BroadcastReceiver mServiceBroadcastReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();
             if (action.equals(ACTION_HIDE_RECENTS_ACTIVITY)) {
                 if (intent.getBooleanExtra(EXTRA_TRIGGERED_FROM_ALT_TAB, false)) {
                     // If we are hiding from releasing Alt-Tab, dismiss Recents to the focused app
                     dismissRecentsToFocusedTaskOrHome(false);
                 } else {
                     // Otherwise, dismiss Recents to Home
                     dismissRecentsToHome(true);
                 }
             } else if (action.equals(ACTION_TOGGLE_RECENTS_ACTIVITY)) {
                 // If we are toggling Recents, then first unfilter any filtered stacks first
                 dismissRecentsToFocusedTaskOrHome(true);
             } else if (action.equals(ACTION_START_ENTER_ANIMATION)) {
                 // Try and start the enter animation (or restart it on configuration changed)
                 ReferenceCountedTrigger t = new ReferenceCountedTrigger(context, null, null, null);
                 mRecentsView.startEnterRecentsAnimation(new ViewAnimation.TaskViewEnterContext(
                         mFullScreenOverlayView, t));
                 onEnterAnimationTriggered();
             }
         }
     };

     /**
      * Broadcast receiver to handle messages from the system
      */
     final BroadcastReceiver mSystemBroadcastReceiver = new BroadcastReceiver() {
         @Override
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();
             if (action.equals(Intent.ACTION_SCREEN_OFF)) {
                 // When the screen turns off, dismiss Recents to Home
                 dismissRecentsToHome(false);
             } else if (action.equals(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED)) {
                 // When the search activity changes, update the Search widget
                 refreshSearchWidget();
             }
         }
     };

     /**
      * A custom debug trigger to listen for a debug key chord.
      */
     final DebugTrigger mDebugTrigger = new DebugTrigger(new Runnable() {
         @Override
         public void run() {
             onDebugModeTriggered();
         }
     });

     /** Updates the set of recent tasks */
     void updateRecentsTasks(Intent launchIntent) {
         RecentsTaskLoader loader = RecentsTaskLoader.getInstance();
         SpaceNode root = loader.reload(this, Constants.Values.RecentsTaskLoader.PreloadFirstTasksCount);
         ArrayList<TaskStack> stacks = root.getStacks();
         if (!stacks.isEmpty()) {
             mRecentsView.setBSP(root);
         }

         // Update the configuration based on the launch intent
         mConfig.launchedFromHome = launchIntent.getBooleanExtra(
                 AlternateRecentsComponent.EXTRA_FROM_HOME, false);
         mConfig.launchedFromAppWithThumbnail = launchIntent.getBooleanExtra(
                 AlternateRecentsComponent.EXTRA_FROM_APP_THUMBNAIL, false);
         mConfig.launchedFromAppWithScreenshot = launchIntent.getBooleanExtra(
                 AlternateRecentsComponent.EXTRA_FROM_APP_FULL_SCREENSHOT, false);
         mConfig.launchedWithAltTab = launchIntent.getBooleanExtra(
                 AlternateRecentsComponent.EXTRA_TRIGGERED_FROM_ALT_TAB, false);
         mConfig.launchedWithNoRecentTasks = !root.hasTasks();
         mConfig.launchedToTaskId = launchIntent.getIntExtra(
                 AlternateRecentsComponent.EXTRA_TRIGGERED_FROM_TASK_ID, -1);

         // Update the top level view's visibilities
         if (mConfig.launchedWithNoRecentTasks) {
             if (mEmptyView == null) {
                 mEmptyView = mEmptyViewStub.inflate();
             }
             mEmptyView.setVisibility(View.VISIBLE);
             mRecentsView.setSearchBarVisibility(View.GONE);
         } else {
             if (mEmptyView != null) {
                 mEmptyView.setVisibility(View.GONE);
             }
             if (mRecentsView.hasSearchBar()) {
                 mRecentsView.setSearchBarVisibility(View.VISIBLE);
             } else {
                 addSearchBarAppWidgetView();
             }
         }

         // Animate the SystemUI scrims into view
         mScrimViews.prepareEnterRecentsAnimation();
     }

     /** Attempts to allocate and bind the search bar app widget */
     void bindSearchBarAppWidget() {
         if (Constants.DebugFlags.App.EnableSearchLayout) {
             SystemServicesProxy ssp = RecentsTaskLoader.getInstance().getSystemServicesProxy();

             // Reset the host view and widget info
             mSearchAppWidgetHostView = null;
             mSearchAppWidgetInfo = null;

             // Try and load the app widget id from the settings
             int appWidgetId = mConfig.searchBarAppWidgetId;
             if (appWidgetId >= 0) {
                 mSearchAppWidgetInfo = ssp.getAppWidgetInfo(appWidgetId);
                 if (mSearchAppWidgetInfo == null) {
                     // If there is no actual widget associated with that id, then delete it and
                     // prepare to bind another app widget in its place
                     ssp.unbindSearchAppWidget(mAppWidgetHost, appWidgetId);
                     appWidgetId = -1;
                 }
             }

             // If there is no id, then bind a new search app widget
             if (appWidgetId < 0) {
                 Pair<Integer, AppWidgetProviderInfo> widgetInfo =
                         ssp.bindSearchAppWidget(mAppWidgetHost);
                 if (widgetInfo != null) {
                     // Save the app widget id into the settings
                     mConfig.updateSearchBarAppWidgetId(this, widgetInfo.first);
                     mSearchAppWidgetInfo = widgetInfo.second;
                 }
             }
         }
     }

     /** Creates the search bar app widget view */
     void addSearchBarAppWidgetView() {
         if (Constants.DebugFlags.App.EnableSearchLayout) {
             int appWidgetId = mConfig.searchBarAppWidgetId;
             if (appWidgetId >= 0) {
                 mSearchAppWidgetHostView = mAppWidgetHost.createView(this, appWidgetId,
                         mSearchAppWidgetInfo);
                 Bundle opts = new Bundle();
                 opts.putInt(AppWidgetManager.OPTION_APPWIDGET_HOST_CATEGORY,
                         AppWidgetProviderInfo.WIDGET_CATEGORY_RECENTS);
                 mSearchAppWidgetHostView.updateAppWidgetOptions(opts);
                 // Set the padding to 0 for this search widget
                 mSearchAppWidgetHostView.setPadding(0, 0, 0, 0);
                 mRecentsView.setSearchBar(mSearchAppWidgetHostView);
             } else {
                 mRecentsView.setSearchBar(null);
             }
         }
     }

     /** Dismisses recents if we are already visible and the intent is to toggle the recents view */
     boolean dismissRecentsToFocusedTaskOrHome(boolean checkFilteredStackState) {
         if (mVisible) {
             // If we are mid-animation into Recents, reverse the animation now
             if (mFullScreenOverlayView != null &&
                 mFullScreenOverlayView.cancelAnimateOnEnterRecents(mFinishRunnable)) return true;
             // If we currently have filtered stacks, then unfilter those first
             if (checkFilteredStackState &&
                 mRecentsView.unfilterFilteredStacks()) return true;
             // If we have a focused Task, launch that Task now
             if (mRecentsView.launchFocusedTask()) return true;
             // If we launched from Home, then return to Home
             if (mConfig.launchedFromHome) {
                 dismissRecentsToHomeRaw(true);
                 return true;
             }
             // Otherwise, try and return to the first Task in the stack
             if (mRecentsView.launchFirstTask()) return true;
             // If none of the other cases apply, then just go Home
             dismissRecentsToHomeRaw(true);
             return true;
         }
         return false;
     }

     /** Dismisses Recents directly to Home. */
     void dismissRecentsToHomeRaw(boolean animated) {
         if (animated) {
             ReferenceCountedTrigger exitTrigger = new ReferenceCountedTrigger(this,
                     null, mFinishLaunchHomeRunnable, null);
             mRecentsView.startExitToHomeAnimation(
                     new ViewAnimation.TaskViewExitContext(exitTrigger));
         } else {
             mFinishLaunchHomeRunnable.run();
         }
     }

     /** Dismisses Recents directly to Home if we currently aren't transitioning. */
     boolean dismissRecentsToHome(boolean animated) {
         if (mVisible) {
             // If we are mid-animation into Recents, reverse the animation now
             if (mFullScreenOverlayView != null &&
                 mFullScreenOverlayView.cancelAnimateOnEnterRecents(mFinishRunnable)) return true;
             // Return to Home
             dismissRecentsToHomeRaw(animated);
             return true;
         }
         return false;
     }

     /** Called with the activity is first created. */
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         // Initialize the loader and the configuration
         RecentsTaskLoader.initialize(this);
         mConfig = RecentsConfiguration.reinitialize(this);

         // Create the home intent runnable
         Intent homeIntent = new Intent(Intent.ACTION_MAIN, null);
         homeIntent.addCategory(Intent.CATEGORY_HOME);
         homeIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
                             Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
         mFinishLaunchHomeRunnable = new FinishRecentsRunnable(homeIntent,
                 ActivityOptions.makeCustomAnimation(this, R.anim.recents_to_launcher_enter,
                         R.anim.recents_to_launcher_exit));

         // Initialize the widget host (the host id is static and does not change)
         mAppWidgetHost = new RecentsAppWidgetHost(this, Constants.Values.App.AppWidgetHostId);

         // Set the Recents layout
         setContentView(R.layout.recents);
         mRecentsView = (RecentsView) findViewById(R.id.recents_view);
         mRecentsView.setCallbacks(this);
         mRecentsView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE |
                 View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN |
                 View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
         mEmptyViewStub = (ViewStub) findViewById(R.id.empty_view_stub);
         mFullscreenOverlayStub = (ViewStub) findViewById(R.id.fullscreen_overlay_stub);
         mScrimViews = new SystemBarScrimViews(this, mConfig);

         // Bind the search app widget when we first start up
         bindSearchBarAppWidget();
         // Update the recent tasks
         updateRecentsTasks(getIntent());

         // Register the broadcast receiver to handle messages when the screen is turned off
         IntentFilter filter = new IntentFilter();
         filter.addAction(Intent.ACTION_SCREEN_OFF);
         filter.addAction(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED);
         registerReceiver(mSystemBroadcastReceiver, filter);

         // Register any broadcast receivers for the task loader
         RecentsTaskLoader.getInstance().registerReceivers(this, mRecentsView);

         // Private API calls to make the shadows look better
         try {
             Utilities.setShadowProperty("ambientShadowStrength", String.valueOf(35f));
             Utilities.setShadowProperty("ambientRatio", String.valueOf(0.5f));
         } catch (IllegalAccessException e) {
             e.printStackTrace();
         } catch (InvocationTargetException e) {
             e.printStackTrace();
         }

         // Prepare the screenshot transition if necessary
         if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
             mFullScreenOverlayView = (FullscreenTransitionOverlayView) mFullscreenOverlayStub.inflate();
             mFullScreenOverlayView.setCallbacks(this);
             mFullScreenOverlayView.prepareAnimateOnEnterRecents(AlternateRecentsComponent.getLastScreenshot());
         }

         // Update if we are getting a configuration change
         if (savedInstanceState != null) {
             mConfig.updateOnConfigurationChange();
             onConfigurationChange();
         }
     }

     void onConfigurationChange() {
         // Update RecentsConfiguration
         mConfig = RecentsConfiguration.reinitialize(this);

         // Try and start the enter animation (or restart it on configuration changed)
         ReferenceCountedTrigger t = new ReferenceCountedTrigger(this, null, null, null);
         mRecentsView.startEnterRecentsAnimation(new ViewAnimation.TaskViewEnterContext(
                 mFullScreenOverlayView, t));
         onEnterAnimationTriggered();
     }

     @Override
     protected void onNewIntent(Intent intent) {
         super.onNewIntent(intent);
         setIntent(intent);

         // Update the recent tasks
         updateRecentsTasks(intent);

         // Prepare the screenshot transition if necessary
         if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
             mFullScreenOverlayView.prepareAnimateOnEnterRecents(AlternateRecentsComponent.getLastScreenshot());
         }
     }

     @Override
     protected void onStart() {
         super.onStart();

         // Register the broadcast receiver to handle messages from our service
         IntentFilter filter = new IntentFilter();
         filter.addAction(ACTION_HIDE_RECENTS_ACTIVITY);
         filter.addAction(ACTION_TOGGLE_RECENTS_ACTIVITY);
         filter.addAction(ACTION_START_ENTER_ANIMATION);
         registerReceiver(mServiceBroadcastReceiver, filter);
     }

     @Override
     protected void onResume() {
         super.onResume();

         // Start listening for widget package changes if there is one bound, post it since we don't
         // want it stalling the startup
         if (mConfig.searchBarAppWidgetId >= 0) {
             final WeakReference<RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks> callback =
                     new WeakReference<RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks>(this);
             mRecentsView.postDelayed(new Runnable() {
                 @Override
                 public void run() {
                     RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks cb = callback.get();
                     if (cb != null) {
                         mAppWidgetHost.startListening(cb);
                     }
                 }
             }, 1);
         }

         // Mark Recents as visible
         mVisible = true;
     }

     @Override
     protected void onStop() {
         super.onStop();

         // Unregister the RecentsService receiver
         unregisterReceiver(mServiceBroadcastReceiver);

         // Stop listening for widget package changes if there was one bound
         if (mAppWidgetHost.isListening()) {
             mAppWidgetHost.stopListening();
         }
     }

     @Override
     protected void onDestroy() {
         super.onDestroy();

         // Unregister the system broadcast receivers
         unregisterReceiver(mSystemBroadcastReceiver);
         RecentsTaskLoader.getInstance().unregisterReceivers();
     }

     @Override
     public void onTrimMemory(int level) {
         RecentsTaskLoader loader = RecentsTaskLoader.getInstance();
         if (loader != null) {
             loader.onTrimMemory(level);
         }
     }

     @Override
     public boolean onKeyDown(int keyCode, KeyEvent event) {
         if (keyCode == KeyEvent.KEYCODE_TAB) {
             // Focus the next task in the stack
             final boolean backward = event.isShiftPressed();
             mRecentsView.focusNextTask(!backward);
             return true;
         } else if (keyCode == KeyEvent.KEYCODE_DPAD_UP) {
             mRecentsView.focusNextTask(true);
             return true;
         } else if (keyCode == KeyEvent.KEYCODE_DPAD_DOWN) {
             mRecentsView.focusNextTask(false);
             return true;
         }
         // Pass through the debug trigger
         mDebugTrigger.onKeyEvent(keyCode);
         return super.onKeyDown(keyCode, event);
     }

     @Override
     public void onUserInteraction() {
         mRecentsView.onUserInteraction();
     }

     @Override
     public void onBackPressed() {
         // Test mode where back does not do anything
         if (mConfig.debugModeEnabled) return;

         // Dismiss Recents to the focused Task or Home
         dismissRecentsToFocusedTaskOrHome(true);
     }

     /** Called when debug mode is triggered */
     public void onDebugModeTriggered() {
         if (mConfig.developerOptionsEnabled) {
             SharedPreferences settings = getSharedPreferences(getPackageName(), 0);
             if (settings.getBoolean(Constants.Values.App.Key_DebugModeEnabled, false)) {
                 // Disable the debug mode
                 settings.edit().remove(Constants.Values.App.Key_DebugModeEnabled).apply();
             } else {
                 // Enable the debug mode
                 settings.edit().putBoolean(Constants.Values.App.Key_DebugModeEnabled, true).apply();
             }
             Toast.makeText(this, "Debug mode (" + Constants.Values.App.DebugModeVersion +
                     ") toggled, please restart Recents now", Toast.LENGTH_SHORT).show();
         }
     }

     /** Called when the enter recents animation is triggered. */
     public void onEnterAnimationTriggered() {
         // Animate the SystemUI scrim views
         mScrimViews.startEnterRecentsAnimation();
     }

     /**** FullscreenTransitionOverlayView.FullScreenTransitionViewCallbacks Implementation ****/

     @Override
     public void onEnterAnimationComplete() {
         // Reset the full screenshot transition view
         if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
             mFullScreenOverlayView.reset();

             // Recycle the full screen screenshot
             AlternateRecentsComponent.consumeLastScreenshot();
         }
     }

     /**** RecentsView.RecentsViewCallbacks Implementation ****/

     @Override
     public void onExitToHomeAnimationTriggered() {
         // Animate the SystemUI scrim views out
         mScrimViews.startExitRecentsAnimation();
     }

     @Override
     public void onTaskViewClicked() {
         // Mark recents as no longer visible
         AlternateRecentsComponent.notifyVisibilityChanged(false);
         mVisible = false;
     }

     @Override
     public void onAllTaskViewsDismissed() {
         mFinishLaunchHomeRunnable.run();
     }

     /**** RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks Implementation ****/

     @Override
     public void refreshSearchWidget() {
         bindSearchBarAppWidget();
         addSearchBarAppWidgetView();
     }
 }
	/*
	* Copyright (C) 2014 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.systemui.recents;

	import android.app.Activity;
	import android.app.ActivityOptions;
	import android.app.SearchManager;
	import android.appwidget.AppWidgetHostView;
	import android.appwidget.AppWidgetManager;
	import android.appwidget.AppWidgetProviderInfo;
	import android.content.BroadcastReceiver;
	import android.content.Context;
	import android.content.Intent;
	import android.content.IntentFilter;
	import android.content.SharedPreferences;
	import android.os.Bundle;
	import android.os.UserHandle;
	import android.util.Pair;
	import android.view.KeyEvent;
	import android.view.View;
	import android.view.ViewStub;
	import android.widget.Toast;
	import com.android.systemui.R;
	import com.android.systemui.recents.misc.Console;
	import com.android.systemui.recents.misc.DebugTrigger;
	import com.android.systemui.recents.misc.ReferenceCountedTrigger;
	import com.android.systemui.recents.misc.SystemServicesProxy;
	import com.android.systemui.recents.misc.Utilities;
	import com.android.systemui.recents.model.RecentsTaskLoader;
	import com.android.systemui.recents.model.SpaceNode;
	import com.android.systemui.recents.model.TaskStack;
	import com.android.systemui.recents.views.FullscreenTransitionOverlayView;
	import com.android.systemui.recents.views.RecentsView;
	import com.android.systemui.recents.views.SystemBarScrimViews;
	import com.android.systemui.recents.views.ViewAnimation;

	import java.lang.ref.WeakReference;
	import java.lang.reflect.InvocationTargetException;
	import java.util.ArrayList;

	/**
	* The main Recents activity that is started from AlternateRecentsComponent.
	*/
	public class RecentsActivity extends Activity implements RecentsView.RecentsViewCallbacks,
	RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks,
	FullscreenTransitionOverlayView.FullScreenTransitionViewCallbacks {

	// Actions and Extras sent from AlternateRecentsComponent
	final static String EXTRA_TRIGGERED_FROM_ALT_TAB = "extra_triggered_from_alt_tab";
	final static String ACTION_START_ENTER_ANIMATION = "action_start_enter_animation";
	final static String ACTION_TOGGLE_RECENTS_ACTIVITY = "action_toggle_recents_activity";
	final static String ACTION_HIDE_RECENTS_ACTIVITY = "action_hide_recents_activity";

	RecentsConfiguration mConfig;
	boolean mVisible;

	// Top level views
	RecentsView mRecentsView;
	SystemBarScrimViews mScrimViews;
	ViewStub mEmptyViewStub;
	View mEmptyView;
	ViewStub mFullscreenOverlayStub;
	FullscreenTransitionOverlayView mFullScreenOverlayView;

	// Search AppWidget
	RecentsAppWidgetHost mAppWidgetHost;
	AppWidgetProviderInfo mSearchAppWidgetInfo;
	AppWidgetHostView mSearchAppWidgetHostView;


	// Runnables to finish the Recents activity
	FinishRecentsRunnable mFinishRunnable = new FinishRecentsRunnable();
	FinishRecentsRunnable mFinishLaunchHomeRunnable;

	/**
	* A common Runnable to finish Recents either by calling finish() (with a custom animation) or
	* launching Home with some ActivityOptions. Generally we always launch home when we exit
	* Recents rather than just finishing the activity since we don't know what is behind Recents in
	* the task stack. The only case where we finish() directly is when we are cancelling the full
	* screen transition from the app.
	*/
	class FinishRecentsRunnable implements Runnable {
	Intent mLaunchIntent;
	ActivityOptions mLaunchOpts;

	public FinishRecentsRunnable() {
	// Do nothing
	}

	/**
	* Creates a finish runnable that starts the specified intent, using the given
	* ActivityOptions.
	*/
	public FinishRecentsRunnable(Intent launchIntent, ActivityOptions opts) {
	mLaunchIntent = launchIntent;
	mLaunchOpts = opts;
	}

	@Override
	public void run() {
	// Mark Recents as no longer visible
	AlternateRecentsComponent.notifyVisibilityChanged(false);
	mVisible = false;
	// Finish Recents
	if (mLaunchIntent != null) {
	if (mLaunchOpts != null) {
	startActivityAsUser(mLaunchIntent, UserHandle.CURRENT);
	} else {
	startActivityAsUser(mLaunchIntent, mLaunchOpts.toBundle(), UserHandle.CURRENT);
	}
	} else {
	finish();
	overridePendingTransition(R.anim.recents_to_launcher_enter,
	R.anim.recents_to_launcher_exit);
	}
	}
	}

	/**
	* Broadcast receiver to handle messages from AlternateRecentsComponent.
	*/
	final BroadcastReceiver mServiceBroadcastReceiver = new BroadcastReceiver() {
	@Override
	public void onReceive(Context context, Intent intent) {
	String action = intent.getAction();
	if (action.equals(ACTION_HIDE_RECENTS_ACTIVITY)) {
	if (intent.getBooleanExtra(EXTRA_TRIGGERED_FROM_ALT_TAB, false)) {
	// If we are hiding from releasing Alt-Tab, dismiss Recents to the focused app
	dismissRecentsToFocusedTaskOrHome(false);
	} else {
	// Otherwise, dismiss Recents to Home
	dismissRecentsToHome(true);
	}
	} else if (action.equals(ACTION_TOGGLE_RECENTS_ACTIVITY)) {
	// If we are toggling Recents, then first unfilter any filtered stacks first
	dismissRecentsToFocusedTaskOrHome(true);
	} else if (action.equals(ACTION_START_ENTER_ANIMATION)) {
	// Try and start the enter animation (or restart it on configuration changed)
	ReferenceCountedTrigger t = new ReferenceCountedTrigger(context, null, null, null);
	mRecentsView.startEnterRecentsAnimation(new ViewAnimation.TaskViewEnterContext(
	mFullScreenOverlayView, t));
	onEnterAnimationTriggered();
	}
	}
	};

	/**
	* Broadcast receiver to handle messages from the system
	*/
	final BroadcastReceiver mSystemBroadcastReceiver = new BroadcastReceiver() {
	@Override
	public void onReceive(Context context, Intent intent) {
	String action = intent.getAction();
	if (action.equals(Intent.ACTION_SCREEN_OFF)) {
	// When the screen turns off, dismiss Recents to Home
	dismissRecentsToHome(false);
	} else if (action.equals(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED)) {
	// When the search activity changes, update the Search widget
	refreshSearchWidget();
	}
	}
	};

	/**
	* A custom debug trigger to listen for a debug key chord.
	*/
	final DebugTrigger mDebugTrigger = new DebugTrigger(new Runnable() {
	@Override
	public void run() {
	onDebugModeTriggered();
	}
	});

	/** Updates the set of recent tasks */
	void updateRecentsTasks(Intent launchIntent) {
	RecentsTaskLoader loader = RecentsTaskLoader.getInstance();
	SpaceNode root = loader.reload(this, Constants.Values.RecentsTaskLoader.PreloadFirstTasksCount);
	ArrayList<TaskStack> stacks = root.getStacks();
	if (!stacks.isEmpty()) {
	mRecentsView.setBSP(root);
	}

	// Update the configuration based on the launch intent
	mConfig.launchedFromHome = launchIntent.getBooleanExtra(
	AlternateRecentsComponent.EXTRA_FROM_HOME, false);
	mConfig.launchedFromAppWithThumbnail = launchIntent.getBooleanExtra(
	AlternateRecentsComponent.EXTRA_FROM_APP_THUMBNAIL, false);
	mConfig.launchedFromAppWithScreenshot = launchIntent.getBooleanExtra(
	AlternateRecentsComponent.EXTRA_FROM_APP_FULL_SCREENSHOT, false);
	mConfig.launchedWithAltTab = launchIntent.getBooleanExtra(
	AlternateRecentsComponent.EXTRA_TRIGGERED_FROM_ALT_TAB, false);
	mConfig.launchedWithNoRecentTasks = !root.hasTasks();
	mConfig.launchedToTaskId = launchIntent.getIntExtra(
	AlternateRecentsComponent.EXTRA_TRIGGERED_FROM_TASK_ID, -1);

	// Update the top level view's visibilities
	if (mConfig.launchedWithNoRecentTasks) {
	if (mEmptyView == null) {
	mEmptyView = mEmptyViewStub.inflate();
	}
	mEmptyView.setVisibility(View.VISIBLE);
	mRecentsView.setSearchBarVisibility(View.GONE);
	} else {
	if (mEmptyView != null) {
	mEmptyView.setVisibility(View.GONE);
	}
	if (mRecentsView.hasSearchBar()) {
	mRecentsView.setSearchBarVisibility(View.VISIBLE);
	} else {
	addSearchBarAppWidgetView();
	}
	}

	// Animate the SystemUI scrims into view
	mScrimViews.prepareEnterRecentsAnimation();
	}

	/** Attempts to allocate and bind the search bar app widget */
	void bindSearchBarAppWidget() {
	if (Constants.DebugFlags.App.EnableSearchLayout) {
	SystemServicesProxy ssp = RecentsTaskLoader.getInstance().getSystemServicesProxy();

	// Reset the host view and widget info
	mSearchAppWidgetHostView = null;
	mSearchAppWidgetInfo = null;

	// Try and load the app widget id from the settings
	int appWidgetId = mConfig.searchBarAppWidgetId;
	if (appWidgetId >= 0) {
	mSearchAppWidgetInfo = ssp.getAppWidgetInfo(appWidgetId);
	if (mSearchAppWidgetInfo == null) {
	// If there is no actual widget associated with that id, then delete it and
	// prepare to bind another app widget in its place
	ssp.unbindSearchAppWidget(mAppWidgetHost, appWidgetId);
	appWidgetId = -1;
	}
	}

	// If there is no id, then bind a new search app widget
	if (appWidgetId < 0) {
	Pair<Integer, AppWidgetProviderInfo> widgetInfo =
	ssp.bindSearchAppWidget(mAppWidgetHost);
	if (widgetInfo != null) {
	// Save the app widget id into the settings
	mConfig.updateSearchBarAppWidgetId(this, widgetInfo.first);
	mSearchAppWidgetInfo = widgetInfo.second;
	}
	}
	}
	}

	/** Creates the search bar app widget view */
	void addSearchBarAppWidgetView() {
	if (Constants.DebugFlags.App.EnableSearchLayout) {
	int appWidgetId = mConfig.searchBarAppWidgetId;
	if (appWidgetId >= 0) {
	mSearchAppWidgetHostView = mAppWidgetHost.createView(this, appWidgetId,
	mSearchAppWidgetInfo);
	Bundle opts = new Bundle();
	opts.putInt(AppWidgetManager.OPTION_APPWIDGET_HOST_CATEGORY,
	AppWidgetProviderInfo.WIDGET_CATEGORY_RECENTS);
	mSearchAppWidgetHostView.updateAppWidgetOptions(opts);
	// Set the padding to 0 for this search widget
	mSearchAppWidgetHostView.setPadding(0, 0, 0, 0);
	mRecentsView.setSearchBar(mSearchAppWidgetHostView);
	} else {
	mRecentsView.setSearchBar(null);
	}
	}
	}

	/** Dismisses recents if we are already visible and the intent is to toggle the recents view */
	boolean dismissRecentsToFocusedTaskOrHome(boolean checkFilteredStackState) {
	if (mVisible) {
	// If we are mid-animation into Recents, reverse the animation now
	if (mFullScreenOverlayView != null &&
	mFullScreenOverlayView.cancelAnimateOnEnterRecents(mFinishRunnable)) return true;
	// If we currently have filtered stacks, then unfilter those first
	if (checkFilteredStackState &&
	mRecentsView.unfilterFilteredStacks()) return true;
	// If we have a focused Task, launch that Task now
	if (mRecentsView.launchFocusedTask()) return true;
	// If we launched from Home, then return to Home
	if (mConfig.launchedFromHome) {
	dismissRecentsToHomeRaw(true);
	return true;
	}
	// Otherwise, try and return to the first Task in the stack
	if (mRecentsView.launchFirstTask()) return true;
	// If none of the other cases apply, then just go Home
	dismissRecentsToHomeRaw(true);
	return true;
	}
	return false;
	}

	/** Dismisses Recents directly to Home. */
	void dismissRecentsToHomeRaw(boolean animated) {
	if (animated) {
	ReferenceCountedTrigger exitTrigger = new ReferenceCountedTrigger(this,
	null, mFinishLaunchHomeRunnable, null);
	mRecentsView.startExitToHomeAnimation(
	new ViewAnimation.TaskViewExitContext(exitTrigger));
	} else {
	mFinishLaunchHomeRunnable.run();
	}
	}

	/** Dismisses Recents directly to Home if we currently aren't transitioning. */
	boolean dismissRecentsToHome(boolean animated) {
	if (mVisible) {
	// If we are mid-animation into Recents, reverse the animation now
	if (mFullScreenOverlayView != null &&
	mFullScreenOverlayView.cancelAnimateOnEnterRecents(mFinishRunnable)) return true;
	// Return to Home
	dismissRecentsToHomeRaw(animated);
	return true;
	}
	return false;
	}

	/** Called with the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	// Initialize the loader and the configuration
	RecentsTaskLoader.initialize(this);
	mConfig = RecentsConfiguration.reinitialize(this);

	// Create the home intent runnable
	Intent homeIntent = new Intent(Intent.ACTION_MAIN, null);
	homeIntent.addCategory(Intent.CATEGORY_HOME);
	homeIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK \|
	Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
	mFinishLaunchHomeRunnable = new FinishRecentsRunnable(homeIntent,
	ActivityOptions.makeCustomAnimation(this, R.anim.recents_to_launcher_enter,
	R.anim.recents_to_launcher_exit));

	// Initialize the widget host (the host id is static and does not change)
	mAppWidgetHost = new RecentsAppWidgetHost(this, Constants.Values.App.AppWidgetHostId);

	// Set the Recents layout
	setContentView(R.layout.recents);
	mRecentsView = (RecentsView) findViewById(R.id.recents_view);
	mRecentsView.setCallbacks(this);
	mRecentsView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE \|
	View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN \|
	View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
	mEmptyViewStub = (ViewStub) findViewById(R.id.empty_view_stub);
	mFullscreenOverlayStub = (ViewStub) findViewById(R.id.fullscreen_overlay_stub);
	mScrimViews = new SystemBarScrimViews(this, mConfig);

	// Bind the search app widget when we first start up
	bindSearchBarAppWidget();
	// Update the recent tasks
	updateRecentsTasks(getIntent());

	// Register the broadcast receiver to handle messages when the screen is turned off
	IntentFilter filter = new IntentFilter();
	filter.addAction(Intent.ACTION_SCREEN_OFF);
	filter.addAction(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED);
	registerReceiver(mSystemBroadcastReceiver, filter);

	// Register any broadcast receivers for the task loader
	RecentsTaskLoader.getInstance().registerReceivers(this, mRecentsView);

	// Private API calls to make the shadows look better
	try {
	Utilities.setShadowProperty("ambientShadowStrength", String.valueOf(35f));
	Utilities.setShadowProperty("ambientRatio", String.valueOf(0.5f));
	} catch (IllegalAccessException e) {
	e.printStackTrace();
	} catch (InvocationTargetException e) {
	e.printStackTrace();
	}

	// Prepare the screenshot transition if necessary
	if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
	mFullScreenOverlayView = (FullscreenTransitionOverlayView) mFullscreenOverlayStub.inflate();
	mFullScreenOverlayView.setCallbacks(this);
	mFullScreenOverlayView.prepareAnimateOnEnterRecents(AlternateRecentsComponent.getLastScreenshot());
	}

	// Update if we are getting a configuration change
	if (savedInstanceState != null) {
	mConfig.updateOnConfigurationChange();
	onConfigurationChange();
	}
	}

	void onConfigurationChange() {
	// Update RecentsConfiguration
	mConfig = RecentsConfiguration.reinitialize(this);

	// Try and start the enter animation (or restart it on configuration changed)
	ReferenceCountedTrigger t = new ReferenceCountedTrigger(this, null, null, null);
	mRecentsView.startEnterRecentsAnimation(new ViewAnimation.TaskViewEnterContext(
	mFullScreenOverlayView, t));
	onEnterAnimationTriggered();
	}

	@Override
	protected void onNewIntent(Intent intent) {
	super.onNewIntent(intent);
	setIntent(intent);

	// Update the recent tasks
	updateRecentsTasks(intent);

	// Prepare the screenshot transition if necessary
	if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
	mFullScreenOverlayView.prepareAnimateOnEnterRecents(AlternateRecentsComponent.getLastScreenshot());
	}
	}

	@Override
	protected void onStart() {
	super.onStart();

	// Register the broadcast receiver to handle messages from our service
	IntentFilter filter = new IntentFilter();
	filter.addAction(ACTION_HIDE_RECENTS_ACTIVITY);
	filter.addAction(ACTION_TOGGLE_RECENTS_ACTIVITY);
	filter.addAction(ACTION_START_ENTER_ANIMATION);
	registerReceiver(mServiceBroadcastReceiver, filter);
	}

	@Override
	protected void onResume() {
	super.onResume();

	// Start listening for widget package changes if there is one bound, post it since we don't
	// want it stalling the startup
	if (mConfig.searchBarAppWidgetId >= 0) {
	final WeakReference<RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks> callback =
	new WeakReference<RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks>(this);
	mRecentsView.postDelayed(new Runnable() {
	@Override
	public void run() {
	RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks cb = callback.get();
	if (cb != null) {
	mAppWidgetHost.startListening(cb);
	}
	}
	}, 1);
	}

	// Mark Recents as visible
	mVisible = true;
	}

	@Override
	protected void onStop() {
	super.onStop();

	// Unregister the RecentsService receiver
	unregisterReceiver(mServiceBroadcastReceiver);

	// Stop listening for widget package changes if there was one bound
	if (mAppWidgetHost.isListening()) {
	mAppWidgetHost.stopListening();
	}
	}

	@Override
	protected void onDestroy() {
	super.onDestroy();

	// Unregister the system broadcast receivers
	unregisterReceiver(mSystemBroadcastReceiver);
	RecentsTaskLoader.getInstance().unregisterReceivers();
	}

	@Override
	public void onTrimMemory(int level) {
	RecentsTaskLoader loader = RecentsTaskLoader.getInstance();
	if (loader != null) {
	loader.onTrimMemory(level);
	}
	}

	@Override
	public boolean onKeyDown(int keyCode, KeyEvent event) {
	if (keyCode == KeyEvent.KEYCODE_TAB) {
	// Focus the next task in the stack
	final boolean backward = event.isShiftPressed();
	mRecentsView.focusNextTask(!backward);
	return true;
	} else if (keyCode == KeyEvent.KEYCODE_DPAD_UP) {
	mRecentsView.focusNextTask(true);
	return true;
	} else if (keyCode == KeyEvent.KEYCODE_DPAD_DOWN) {
	mRecentsView.focusNextTask(false);
	return true;
	}
	// Pass through the debug trigger
	mDebugTrigger.onKeyEvent(keyCode);
	return super.onKeyDown(keyCode, event);
	}

	@Override
	public void onUserInteraction() {
	mRecentsView.onUserInteraction();
	}

	@Override
	public void onBackPressed() {
	// Test mode where back does not do anything
	if (mConfig.debugModeEnabled) return;

	// Dismiss Recents to the focused Task or Home
	dismissRecentsToFocusedTaskOrHome(true);
	}

	/** Called when debug mode is triggered */
	public void onDebugModeTriggered() {
	if (mConfig.developerOptionsEnabled) {
	SharedPreferences settings = getSharedPreferences(getPackageName(), 0);
	if (settings.getBoolean(Constants.Values.App.Key_DebugModeEnabled, false)) {
	// Disable the debug mode
	settings.edit().remove(Constants.Values.App.Key_DebugModeEnabled).apply();
	} else {
	// Enable the debug mode
	settings.edit().putBoolean(Constants.Values.App.Key_DebugModeEnabled, true).apply();
	}
	Toast.makeText(this, "Debug mode (" + Constants.Values.App.DebugModeVersion +
	") toggled, please restart Recents now", Toast.LENGTH_SHORT).show();
	}
	}

	/** Called when the enter recents animation is triggered. */
	public void onEnterAnimationTriggered() {
	// Animate the SystemUI scrim views
	mScrimViews.startEnterRecentsAnimation();
	}

	/** FullscreenTransitionOverlayView.FullScreenTransitionViewCallbacks Implementation **/

	@Override
	public void onEnterAnimationComplete() {
	// Reset the full screenshot transition view
	if (Constants.DebugFlags.App.EnableScreenshotAppTransition) {
	mFullScreenOverlayView.reset();

	// Recycle the full screen screenshot
	AlternateRecentsComponent.consumeLastScreenshot();
	}
	}

	/** RecentsView.RecentsViewCallbacks Implementation **/

	@Override
	public void onExitToHomeAnimationTriggered() {
	// Animate the SystemUI scrim views out
	mScrimViews.startExitRecentsAnimation();
	}

	@Override
	public void onTaskViewClicked() {
	// Mark recents as no longer visible
	AlternateRecentsComponent.notifyVisibilityChanged(false);
	mVisible = false;
	}

	@Override
	public void onAllTaskViewsDismissed() {
	mFinishLaunchHomeRunnable.run();
	}

	/** RecentsAppWidgetHost.RecentsAppWidgetHostCallbacks Implementation **/

	@Override
	public void refreshSearchWidget() {
	bindSearchBarAppWidget();
	addSearchBarAppWidgetView();
	}
	}