RecentsView.java revision 250608a5cd08862f4752a924d51710805850db8a 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.systemui.recents.views;
18
19import android.content.Context;
20import android.content.res.Resources;
21import android.graphics.Canvas;
22import android.graphics.Rect;
23import android.graphics.drawable.Drawable;
24import android.os.Handler;
25import android.util.ArraySet;
26import android.util.AttributeSet;
27import android.view.LayoutInflater;
28import android.view.MotionEvent;
29import android.view.View;
30import android.view.WindowInsets;
31import android.view.animation.AnimationUtils;
32import android.view.animation.Interpolator;
33import android.widget.FrameLayout;
34import com.android.systemui.R;
35import com.android.systemui.recents.Recents;
36import com.android.systemui.recents.RecentsActivity;
37import com.android.systemui.recents.RecentsActivityLaunchState;
38import com.android.systemui.recents.RecentsAppWidgetHostView;
39import com.android.systemui.recents.RecentsConfiguration;
40import com.android.systemui.recents.RecentsDebugFlags;
41import com.android.systemui.recents.events.EventBus;
42import com.android.systemui.recents.events.activity.CancelEnterRecentsWindowAnimationEvent;
43import com.android.systemui.recents.events.activity.DebugFlagsChangedEvent;
44import com.android.systemui.recents.events.activity.DismissRecentsToHomeAnimationStarted;
45import com.android.systemui.recents.events.activity.HideHistoryButtonEvent;
46import com.android.systemui.recents.events.activity.HideHistoryEvent;
47import com.android.systemui.recents.events.activity.ShowHistoryButtonEvent;
48import com.android.systemui.recents.events.activity.ShowHistoryEvent;
49import com.android.systemui.recents.events.component.RecentsVisibilityChangedEvent;
50import com.android.systemui.recents.events.ui.DraggingInRecentsEndedEvent;
51import com.android.systemui.recents.events.ui.DraggingInRecentsEvent;
52import com.android.systemui.recents.events.ui.dragndrop.DragDropTargetChangedEvent;
53import com.android.systemui.recents.events.ui.dragndrop.DragEndEvent;
54import com.android.systemui.recents.events.ui.dragndrop.DragStartEvent;
55import com.android.systemui.recents.misc.SystemServicesProxy;
56import com.android.systemui.recents.model.Task;
57import com.android.systemui.recents.model.TaskStack;
58
59import java.util.ArrayList;
60import java.util.List;
61
62import static android.app.ActivityManager.StackId.INVALID_STACK_ID;
63
64/**
65 * This view is the the top level layout that contains TaskStacks (which are laid out according
66 * to their SpaceNode bounds.
67 */
68public class RecentsView extends FrameLayout implements TaskStackView.TaskStackViewCallbacks {
69
70    private static final String TAG = "RecentsView";
71    private static final boolean DEBUG = false;
72
73    Handler mHandler;
74
75    TaskStack mStack;
76    TaskStackView mTaskStackView;
77    RecentsAppWidgetHostView mSearchBar;
78    View mHistoryButton;
79    boolean mAwaitingFirstLayout = true;
80    boolean mLastTaskLaunchedWasFreeform;
81
82    RecentsTransitionHelper mTransitionHelper;
83    RecentsViewTouchHandler mTouchHandler;
84    DragView mDragView;
85    TaskStack.DockState[] mVisibleDockStates = {
86            TaskStack.DockState.LEFT,
87            TaskStack.DockState.TOP,
88            TaskStack.DockState.RIGHT,
89            TaskStack.DockState.BOTTOM,
90    };
91
92    private Interpolator mFastOutSlowInInterpolator;
93    private Interpolator mFastOutLinearInInterpolator;
94    private int mHistoryTransitionDuration;
95
96    Rect mSystemInsets = new Rect();
97
98    public RecentsView(Context context) {
99        super(context);
100    }
101
102    public RecentsView(Context context, AttributeSet attrs) {
103        this(context, attrs, 0);
104    }
105
106    public RecentsView(Context context, AttributeSet attrs, int defStyleAttr) {
107        this(context, attrs, defStyleAttr, 0);
108    }
109
110    public RecentsView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
111        super(context, attrs, defStyleAttr, defStyleRes);
112        Resources res = context.getResources();
113        setWillNotDraw(false);
114        mHandler = new Handler();
115        mTransitionHelper = new RecentsTransitionHelper(getContext(), mHandler);
116        mFastOutSlowInInterpolator = AnimationUtils.loadInterpolator(context,
117                com.android.internal.R.interpolator.fast_out_slow_in);
118        mFastOutLinearInInterpolator = AnimationUtils.loadInterpolator(context,
119                com.android.internal.R.interpolator.fast_out_linear_in);
120        mHistoryTransitionDuration = res.getInteger(R.integer.recents_history_transition_duration);
121        mTouchHandler = new RecentsViewTouchHandler(this);
122
123        LayoutInflater inflater = LayoutInflater.from(context);
124        mHistoryButton = inflater.inflate(R.layout.recents_history_button, this, false);
125        mHistoryButton.setOnClickListener(new View.OnClickListener() {
126            @Override
127            public void onClick(View v) {
128                EventBus.getDefault().send(new ShowHistoryEvent());
129            }
130        });
131    }
132
133    /** Set/get the bsp root node */
134    public void setTaskStack(TaskStack stack) {
135        RecentsConfiguration config = Recents.getConfiguration();
136        mStack = stack;
137        if (config.getLaunchState().launchedReuseTaskStackViews) {
138            if (mTaskStackView != null) {
139                // If onRecentsHidden is not triggered, we need to the stack view again here
140                mTaskStackView.reset();
141                mTaskStackView.setStack(stack);
142            } else {
143                mTaskStackView = new TaskStackView(getContext(), stack);
144                mTaskStackView.setCallbacks(this);
145                addView(mTaskStackView);
146            }
147        } else {
148            if (mTaskStackView != null) {
149                removeView(mTaskStackView);
150            }
151            mTaskStackView = new TaskStackView(getContext(), stack);
152            mTaskStackView.setCallbacks(this);
153            addView(mTaskStackView);
154        }
155        if (indexOfChild(mHistoryButton) == -1) {
156            addView(mHistoryButton);
157        } else {
158            mHistoryButton.bringToFront();
159        }
160
161        // Trigger a new layout
162        requestLayout();
163    }
164
165    /**
166     * Returns whether the last task launched was in the freeform stack or not.
167     */
168    public boolean isLastTaskLaunchedFreeform() {
169        return mLastTaskLaunchedWasFreeform;
170    }
171
172    /**
173     * Returns the currently set task stack.
174     */
175    public TaskStack getTaskStack() {
176        return mStack;
177    }
178
179    /** Gets the next task in the stack - or if the last - the top task */
180    public Task getNextTaskOrTopTask(Task taskToSearch) {
181        Task returnTask = null;
182        boolean found = false;
183        if (mTaskStackView != null) {
184            TaskStack stack = mTaskStackView.getStack();
185            ArrayList<Task> taskList = stack.getStackTasks();
186            // Iterate the stack views and try and find the focused task
187            for (int j = taskList.size() - 1; j >= 0; --j) {
188                Task task = taskList.get(j);
189                // Return the next task in the line.
190                if (found)
191                    return task;
192                // Remember the first possible task as the top task.
193                if (returnTask == null)
194                    returnTask = task;
195                if (task == taskToSearch)
196                    found = true;
197            }
198        }
199        return returnTask;
200    }
201
202    /** Launches the focused task from the first stack if possible */
203    public boolean launchFocusedTask() {
204        if (mTaskStackView != null) {
205            TaskStack stack = mTaskStackView.getStack();
206            Task task = mTaskStackView.getFocusedTask();
207            if (task != null) {
208                TaskView taskView = mTaskStackView.getChildViewForTask(task);
209                onTaskViewClicked(mTaskStackView, taskView, stack, task, false, null,
210                        INVALID_STACK_ID);
211                return true;
212            }
213        }
214        return false;
215    }
216
217    /** Launches a given task. */
218    public boolean launchTask(Task task, Rect taskBounds, int destinationStack) {
219        if (mTaskStackView != null) {
220            TaskStack stack = mTaskStackView.getStack();
221            // Iterate the stack views and try and find the given task.
222            List<TaskView> taskViews = mTaskStackView.getTaskViews();
223            int taskViewCount = taskViews.size();
224            for (int j = 0; j < taskViewCount; j++) {
225                TaskView tv = taskViews.get(j);
226                if (tv.getTask() == task) {
227                    onTaskViewClicked(mTaskStackView, tv, stack, task, false,
228                            taskBounds, destinationStack);
229                    return true;
230                }
231            }
232        }
233        return false;
234    }
235
236    /** Requests all task stacks to start their enter-recents animation */
237    public void startEnterRecentsAnimation(ViewAnimation.TaskViewEnterContext ctx) {
238        // We have to increment/decrement the post animation trigger in case there are no children
239        // to ensure that it runs
240        ctx.postAnimationTrigger.increment();
241        if (mTaskStackView != null) {
242            mTaskStackView.startEnterRecentsAnimation(ctx);
243        }
244        ctx.postAnimationTrigger.decrement();
245    }
246
247    /** Requests all task stacks to start their exit-recents animation */
248    public void startExitToHomeAnimation(ViewAnimation.TaskViewExitContext ctx) {
249        // We have to increment/decrement the post animation trigger in case there are no children
250        // to ensure that it runs
251        ctx.postAnimationTrigger.increment();
252        if (mTaskStackView != null) {
253            mTaskStackView.startExitToHomeAnimation(ctx);
254        }
255        ctx.postAnimationTrigger.decrement();
256
257        // Hide the history button
258        int taskViewExitToHomeDuration = getResources().getInteger(
259                R.integer.recents_task_exit_to_home_duration);
260        hideHistoryButton(taskViewExitToHomeDuration);
261
262        // If we are going home, cancel the previous task's window transition
263        EventBus.getDefault().send(new CancelEnterRecentsWindowAnimationEvent(null));
264
265        // Notify sof the exit animation
266        EventBus.getDefault().send(new DismissRecentsToHomeAnimationStarted());
267    }
268
269    /** Adds the search bar */
270    public void setSearchBar(RecentsAppWidgetHostView searchBar) {
271        // Remove the previous search bar if one exists
272        if (mSearchBar != null && indexOfChild(mSearchBar) > -1) {
273            removeView(mSearchBar);
274        }
275        // Add the new search bar
276        if (searchBar != null) {
277            mSearchBar = searchBar;
278            addView(mSearchBar);
279        }
280    }
281
282    /** Returns whether there is currently a search bar */
283    public boolean hasValidSearchBar() {
284        return mSearchBar != null && !mSearchBar.isReinflateRequired();
285    }
286
287    /** Sets the visibility of the search bar */
288    public void setSearchBarVisibility(int visibility) {
289        if (mSearchBar != null) {
290            mSearchBar.setVisibility(visibility);
291            // Always bring the search bar to the top
292            mSearchBar.bringToFront();
293        }
294    }
295
296    /**
297     * Returns the last known system insets.
298     */
299    public Rect getSystemInsets() {
300        return mSystemInsets;
301    }
302
303    @Override
304    protected void onAttachedToWindow() {
305        EventBus.getDefault().register(this, RecentsActivity.EVENT_BUS_PRIORITY + 1);
306        EventBus.getDefault().register(mTouchHandler, RecentsActivity.EVENT_BUS_PRIORITY + 1);
307        super.onAttachedToWindow();
308    }
309
310    @Override
311    protected void onDetachedFromWindow() {
312        super.onDetachedFromWindow();
313        EventBus.getDefault().unregister(this);
314        EventBus.getDefault().unregister(mTouchHandler);
315    }
316
317    /**
318     * This is called with the full size of the window since we are handling our own insets.
319     */
320    @Override
321    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
322        RecentsConfiguration config = Recents.getConfiguration();
323        int width = MeasureSpec.getSize(widthMeasureSpec);
324        int height = MeasureSpec.getSize(heightMeasureSpec);
325
326        // Get the search bar bounds and measure the search bar layout
327        Rect searchBarSpaceBounds = new Rect();
328        if (mSearchBar != null) {
329            config.getSearchBarBounds(new Rect(0, 0, width, height), mSystemInsets.top,
330                    searchBarSpaceBounds);
331            mSearchBar.measure(
332                    MeasureSpec.makeMeasureSpec(searchBarSpaceBounds.width(), MeasureSpec.EXACTLY),
333                    MeasureSpec.makeMeasureSpec(searchBarSpaceBounds.height(), MeasureSpec.EXACTLY));
334        }
335
336        Rect taskStackBounds = new Rect();
337        config.getTaskStackBounds(new Rect(0, 0, width, height), mSystemInsets.top,
338                mSystemInsets.right, searchBarSpaceBounds, taskStackBounds);
339        if (mTaskStackView != null && mTaskStackView.getVisibility() != GONE) {
340            mTaskStackView.setTaskStackBounds(taskStackBounds, mSystemInsets);
341            mTaskStackView.measure(widthMeasureSpec, heightMeasureSpec);
342        }
343
344        if (mDragView != null) {
345            Rect taskRect = mTaskStackView.mLayoutAlgorithm.mTaskRect;
346            mDragView.measure(
347                    MeasureSpec.makeMeasureSpec(taskRect.width(), MeasureSpec.AT_MOST),
348                    MeasureSpec.makeMeasureSpec(taskRect.height(), MeasureSpec.AT_MOST));
349        }
350
351        // Measure the history button with the full space above the stack, but width-constrained
352        // to the stack
353        Rect stackRect = mTaskStackView.mLayoutAlgorithm.mCurrentStackRect;
354        measureChild(mHistoryButton,
355                MeasureSpec.makeMeasureSpec(stackRect.width(), MeasureSpec.EXACTLY),
356                MeasureSpec.makeMeasureSpec(mTaskStackView.mLayoutAlgorithm.getStackTopOffset(),
357                        MeasureSpec.EXACTLY));
358        setMeasuredDimension(width, height);
359    }
360
361    /**
362     * This is called with the full size of the window since we are handling our own insets.
363     */
364    @Override
365    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
366        RecentsConfiguration config = Recents.getConfiguration();
367
368        // Get the search bar bounds so that we lay it out
369        Rect measuredRect = new Rect(0, 0, getMeasuredWidth(), getMeasuredHeight());
370        Rect searchBarSpaceBounds = new Rect();
371        if (mSearchBar != null) {
372            config.getSearchBarBounds(measuredRect,
373                    mSystemInsets.top, searchBarSpaceBounds);
374            mSearchBar.layout(searchBarSpaceBounds.left, searchBarSpaceBounds.top,
375                    searchBarSpaceBounds.right, searchBarSpaceBounds.bottom);
376        }
377
378        if (mTaskStackView != null && mTaskStackView.getVisibility() != GONE) {
379            mTaskStackView.layout(left, top, left + getMeasuredWidth(), top + getMeasuredHeight());
380        }
381
382        if (mDragView != null) {
383            mDragView.layout(left, top, left + mDragView.getMeasuredWidth(),
384                    top + mDragView.getMeasuredHeight());
385        }
386
387        // Layout the history button left-aligned with the stack, but offset from the top of the
388        // view
389        Rect stackRect = mTaskStackView.mLayoutAlgorithm.mCurrentStackRect;
390        mHistoryButton.layout(stackRect.left, top + mSystemInsets.top,
391                stackRect.left + mHistoryButton.getMeasuredWidth(),
392                top + mSystemInsets.top + mHistoryButton.getMeasuredHeight());
393
394        if (mAwaitingFirstLayout) {
395            mAwaitingFirstLayout = false;
396
397            // If launched via dragging from the nav bar, then we should translate the whole view
398            // down offscreen
399            RecentsActivityLaunchState launchState = Recents.getConfiguration().getLaunchState();
400            if (launchState.launchedViaDragGesture) {
401                setTranslationY(getMeasuredHeight());
402            }
403        }
404    }
405
406    @Override
407    public WindowInsets onApplyWindowInsets(WindowInsets insets) {
408        mSystemInsets.set(insets.getSystemWindowInsets());
409        requestLayout();
410        return insets;
411    }
412
413    @Override
414    public boolean onInterceptTouchEvent(MotionEvent ev) {
415        return mTouchHandler.onInterceptTouchEvent(ev);
416    }
417
418    @Override
419    public boolean onTouchEvent(MotionEvent ev) {
420        return mTouchHandler.onTouchEvent(ev);
421    }
422
423    @Override
424    protected void dispatchDraw(Canvas canvas) {
425        super.dispatchDraw(canvas);
426        for (int i = mVisibleDockStates.length - 1; i >= 0; i--) {
427            Drawable d = mVisibleDockStates[i].viewState.dockAreaOverlay;
428            if (d.getAlpha() > 0) {
429                d.draw(canvas);
430            }
431        }
432    }
433
434    @Override
435    protected boolean verifyDrawable(Drawable who) {
436        for (int i = mVisibleDockStates.length - 1; i >= 0; i--) {
437            Drawable d = mVisibleDockStates[i].viewState.dockAreaOverlay;
438            if (d == who) {
439                return true;
440            }
441        }
442        return super.verifyDrawable(who);
443    }
444
445    public void disableLayersForOneFrame() {
446        if (mTaskStackView != null) {
447            mTaskStackView.disableLayersForOneFrame();
448        }
449    }
450
451    /**** TaskStackView.TaskStackCallbacks Implementation ****/
452
453    @Override
454    public void onTaskViewClicked(final TaskStackView stackView, final TaskView tv,
455            final TaskStack stack, final Task task, final boolean lockToTask,
456            final Rect bounds, int destinationStack) {
457        mLastTaskLaunchedWasFreeform = SystemServicesProxy.isFreeformStack(task.key.stackId);
458        mTransitionHelper.launchTaskFromRecents(stack, task, stackView, tv, lockToTask, bounds,
459                destinationStack);
460    }
461
462    /**** EventBus Events ****/
463
464    public final void onBusEvent(DragStartEvent event) {
465        // Add the drag view
466        mDragView = event.dragView;
467        addView(mDragView);
468
469        updateVisibleDockRegions(mTouchHandler.getDockStatesForCurrentOrientation(),
470                TaskStack.DockState.NONE.viewState.dockAreaAlpha);
471    }
472
473    public final void onBusEvent(DragDropTargetChangedEvent event) {
474        if (event.dropTarget == null || !(event.dropTarget instanceof TaskStack.DockState)) {
475            updateVisibleDockRegions(mTouchHandler.getDockStatesForCurrentOrientation(),
476                    TaskStack.DockState.NONE.viewState.dockAreaAlpha);
477        } else {
478            final TaskStack.DockState dockState = (TaskStack.DockState) event.dropTarget;
479            updateVisibleDockRegions(new TaskStack.DockState[] {dockState}, -1);
480        }
481    }
482
483    public final void onBusEvent(final DragEndEvent event) {
484        final Runnable cleanUpRunnable = new Runnable() {
485            @Override
486            public void run() {
487                // Remove the drag view
488                removeView(mDragView);
489                mDragView = null;
490            }
491        };
492
493        // Animate the overlay alpha back to 0
494        updateVisibleDockRegions(null, -1);
495
496        if (event.dropTarget == null) {
497            // No drop targets for hit, so just animate the task back to its place
498            event.postAnimationTrigger.increment();
499            event.postAnimationTrigger.addLastDecrementRunnable(new Runnable() {
500                @Override
501                public void run() {
502                    cleanUpRunnable.run();
503                }
504            });
505            // Animate the task back to where it was before then clean up afterwards
506            TaskViewTransform taskTransform = new TaskViewTransform();
507            TaskStackLayoutAlgorithm layoutAlgorithm = mTaskStackView.getStackAlgorithm();
508            layoutAlgorithm.getStackTransform(event.task,
509                    mTaskStackView.getScroller().getStackScroll(), taskTransform, null);
510            event.dragView.animate()
511                    .scaleX(taskTransform.scale)
512                    .scaleY(taskTransform.scale)
513                    .translationX((layoutAlgorithm.mTaskRect.left - event.dragView.getLeft())
514                            + taskTransform.translationX)
515                    .translationY((layoutAlgorithm.mTaskRect.top - event.dragView.getTop())
516                            + taskTransform.translationY)
517                    .setDuration(175)
518                    .setInterpolator(mFastOutSlowInInterpolator)
519                    .withEndAction(event.postAnimationTrigger.decrementAsRunnable())
520                    .start();
521
522        } else if (event.dropTarget instanceof TaskStack.DockState) {
523            final TaskStack.DockState dockState = (TaskStack.DockState) event.dropTarget;
524
525            // For now, just remove the drag view and the original task
526            // TODO: Animate the task to the drop target rect before launching it above
527            cleanUpRunnable.run();
528
529            // Dock the task and launch it
530            SystemServicesProxy ssp = Recents.getSystemServices();
531            ssp.startTaskInDockedMode(event.task.key.id, dockState.createMode);
532            launchTask(event.task, null, INVALID_STACK_ID);
533
534        } else {
535            // We dropped on another drop target, so just add the cleanup to the post animation
536            // trigger
537            event.postAnimationTrigger.addLastDecrementRunnable(new Runnable() {
538                @Override
539                public void run() {
540                    cleanUpRunnable.run();
541                }
542            });
543        }
544    }
545
546    public final void onBusEvent(DraggingInRecentsEvent event) {
547        if (mTaskStackView.getTaskViews().size() > 0) {
548            setTranslationY(event.distanceFromTop - mTaskStackView.getTaskViews().get(0).getY());
549        }
550    }
551
552    public final void onBusEvent(DraggingInRecentsEndedEvent event) {
553        animate().translationY(0f);
554    }
555
556    public final void onBusEvent(ShowHistoryEvent event) {
557        // Hide the history button when the history view is shown
558        hideHistoryButton(mHistoryTransitionDuration);
559    }
560
561    public final void onBusEvent(HideHistoryEvent event) {
562        // Show the history button when the history view is hidden
563        showHistoryButton(mHistoryTransitionDuration);
564    }
565
566    public final void onBusEvent(ShowHistoryButtonEvent event) {
567        showHistoryButton(150);
568    }
569
570    public final void onBusEvent(HideHistoryButtonEvent event) {
571        hideHistoryButton(100);
572    }
573
574    public final void onBusEvent(DebugFlagsChangedEvent event) {
575        RecentsDebugFlags debugFlags = Recents.getDebugFlags();
576        if (!debugFlags.isHistoryEnabled()) {
577            hideHistoryButton(100);
578        }
579    }
580
581    /**
582     * Shows the history button.
583     */
584    private void showHistoryButton(int duration) {
585        RecentsDebugFlags debugFlags = Recents.getDebugFlags();
586        if (!debugFlags.isHistoryEnabled()) {
587            return;
588        }
589
590        mHistoryButton.setVisibility(View.VISIBLE);
591        mHistoryButton.animate()
592                .alpha(1f)
593                .setDuration(duration)
594                .setInterpolator(mFastOutSlowInInterpolator)
595                .withLayer()
596                .start();
597    }
598
599    /**
600     * Hides the history button.
601     */
602    private void hideHistoryButton(int duration) {
603        mHistoryButton.animate()
604                .alpha(0f)
605                .setDuration(duration)
606                .setInterpolator(mFastOutLinearInInterpolator)
607                .withEndAction(new Runnable() {
608                    @Override
609                    public void run() {
610                        mHistoryButton.setVisibility(View.INVISIBLE);
611                    }
612                })
613                .withLayer()
614                .start();
615    }
616
617    /**
618     * Updates the dock region to match the specified dock state.
619     */
620    private void updateVisibleDockRegions(TaskStack.DockState[] newDockStates, int overrideAlpha) {
621        ArraySet<TaskStack.DockState> newDockStatesSet = new ArraySet<>();
622        if (newDockStates != null) {
623            for (TaskStack.DockState dockState : newDockStates) {
624                newDockStatesSet.add(dockState);
625            }
626        }
627        for (TaskStack.DockState dockState : mVisibleDockStates) {
628            TaskStack.DockState.ViewState viewState = dockState.viewState;
629            if (newDockStates == null || !newDockStatesSet.contains(dockState)) {
630                // This is no longer visible, so hide it
631                viewState.startAlphaAnimation(0, 150);
632            } else {
633                // This state is now visible, update the bounds and show it
634                int alpha = (overrideAlpha != -1 ? overrideAlpha : viewState.dockAreaAlpha);
635                viewState.dockAreaOverlay.setBounds(
636                        dockState.getDockedBounds(getMeasuredWidth(), getMeasuredHeight()));
637                viewState.dockAreaOverlay.setCallback(this);
638                viewState.startAlphaAnimation(alpha, 150);
639            }
640        }
641    }
642
643    public final void onBusEvent(RecentsVisibilityChangedEvent event) {
644        if (!event.visible) {
645            // Reset the view state
646            mAwaitingFirstLayout = true;
647            mLastTaskLaunchedWasFreeform = false;
648        }
649    }
650}
651