summaryrefslogtreecommitdiffstats
path: root/services/core/java/com/android/server/wm/TaskStack.java
blob: 480da441593fe428e392f94b104cd97f1fb77e14 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
/*
 * Copyright (C) 2013 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.server.wm;

import static com.android.server.wm.WindowManagerService.DEBUG_TASK_MOVEMENT;
import static com.android.server.wm.WindowManagerService.TAG;

import android.content.res.Configuration;
import android.graphics.Rect;
import android.os.Debug;
import android.util.DisplayMetrics;
import android.util.EventLog;
import android.util.Slog;
import android.util.TypedValue;
import android.view.Surface;

import com.android.server.EventLogTags;

import java.io.PrintWriter;
import java.util.ArrayList;

public class TaskStack {
    /** Amount of time in milliseconds to animate the dim surface from one value to another,
     * when no window animation is driving it. */
    private static final int DEFAULT_DIM_DURATION = 200;
    private static final int DEFAULT_BLUR_DURATION = 50;
    private static final float MAX_BLUR_AMOUNT = 1.0f;

    /** Unique identifier */
    final int mStackId;

    /** The service */
    private final WindowManagerService mService;

    /** The display this stack sits under. */
    private DisplayContent mDisplayContent;

    /** The Tasks that define this stack. Oldest Tasks are at the bottom. The ordering must match
     * mTaskHistory in the ActivityStack with the same mStackId */
    private final ArrayList<Task> mTasks = new ArrayList<Task>();

    /** For comparison with DisplayContent bounds. */
    private Rect mTmpRect = new Rect();
    /** For handling display rotations. */
    private Rect mTmpRect2 = new Rect();

    /** Content limits relative to the DisplayContent this sits in. */
    private Rect mBounds = new Rect();

    /** Whether mBounds is fullscreen */
    private boolean mFullscreen = true;

    /** Used to support {@link android.view.WindowManager.LayoutParams#FLAG_DIM_BEHIND} */
    private DimLayer mDimLayer;

    /** The particular window with FLAG_DIM_BEHIND set. If null, hide mDimLayer. */
    WindowStateAnimator mDimWinAnimator;

    /** Support for non-zero {@link android.view.animation.Animation#getBackgroundColor()} */
    DimLayer mAnimationBackgroundSurface;

    /** The particular window with an Animation with non-zero background color. */
    WindowStateAnimator mAnimationBackgroundAnimator;

    /** Set to false at the start of performLayoutAndPlaceSurfaces. If it is still false by the end
     * then stop any dimming. */
    boolean mDimmingTag;

    boolean mBlurringTag;
    BlurLayer mBlurLayer;
    WindowStateAnimator mBlurWinAnimator;

    /** Application tokens that are exiting, but still on screen for animations. */
    final AppTokenList mExitingAppTokens = new AppTokenList();

    /** Detach this stack from its display when animation completes. */
    boolean mDeferDetach;

    // Contains configurations settings that are different from the global configuration due to
    // stack specific operations. E.g. {@link #setBounds}.
    Configuration mOverrideConfig;
    // True if the stack was forced to fullscreen disregarding the override configuration.
    private boolean mForceFullscreen;
    // The {@link #mBounds} before the stack was forced to fullscreen. Will be restored as the
    // stack bounds once the stack is no longer forced to fullscreen.
    final private Rect mPreForceFullscreenBounds;

    // Device rotation as of the last time {@link #mBounds} was set.
    int mRotation;

    TaskStack(WindowManagerService service, int stackId) {
        mService = service;
        mStackId = stackId;
        mOverrideConfig = Configuration.EMPTY;
        mForceFullscreen = false;
        mPreForceFullscreenBounds = new Rect();
        // TODO: remove bounds from log, they are always 0.
        EventLog.writeEvent(EventLogTags.WM_STACK_CREATED, stackId, mBounds.left, mBounds.top,
                mBounds.right, mBounds.bottom);
    }

    DisplayContent getDisplayContent() {
        return mDisplayContent;
    }

    ArrayList<Task> getTasks() {
        return mTasks;
    }

    void resizeWindows() {
        final ArrayList<WindowState> resizingWindows = mService.mResizingWindows;
        for (int taskNdx = mTasks.size() - 1; taskNdx >= 0; --taskNdx) {
            final ArrayList<AppWindowToken> activities = mTasks.get(taskNdx).mAppTokens;
            for (int activityNdx = activities.size() - 1; activityNdx >= 0; --activityNdx) {
                final ArrayList<WindowState> windows = activities.get(activityNdx).allAppWindows;
                for (int winNdx = windows.size() - 1; winNdx >= 0; --winNdx) {
                    final WindowState win = windows.get(winNdx);
                    if (!resizingWindows.contains(win)) {
                        if (WindowManagerService.DEBUG_RESIZE) Slog.d(TAG,
                                "setBounds: Resizing " + win);
                        resizingWindows.add(win);
                    }
                }
            }
        }
    }

    /** Set the stack bounds. Passing in null sets the bounds to fullscreen. */
    boolean setBounds(Rect bounds) {
        boolean oldFullscreen = mFullscreen;
        int rotation = Surface.ROTATION_0;
        if (mDisplayContent != null) {
            mDisplayContent.getLogicalDisplayRect(mTmpRect);
            rotation = mDisplayContent.getDisplayInfo().rotation;
            if (bounds == null) {
                bounds = mTmpRect;
                mFullscreen = true;
            } else {
                // ensure bounds are entirely within the display rect
                if (!bounds.intersect(mTmpRect)) {
                    // Can't set bounds outside the containing display.. Sorry!
                    return false;
                }
                mFullscreen = mTmpRect.equals(bounds);
            }
        }

        if (bounds == null) {
            // Can't set to fullscreen if we don't have a display to get bounds from...
            return false;
        }
        if (mBounds.equals(bounds) && oldFullscreen == mFullscreen && mRotation == rotation) {
            return false;
        }

        mDimLayer.setBounds(bounds);
        mBlurLayer.setBounds(bounds);
        mAnimationBackgroundSurface.setBounds(bounds);
        mBounds.set(bounds);
        mRotation = rotation;
        updateOverrideConfiguration();
        return true;
    }

    void getBounds(Rect out) {
        out.set(mBounds);
    }

    private void updateOverrideConfiguration() {
        final Configuration serviceConfig = mService.mCurConfiguration;
        if (mFullscreen) {
            mOverrideConfig = Configuration.EMPTY;
            return;
        }

        if (mOverrideConfig == Configuration.EMPTY) {
            mOverrideConfig  = new Configuration();
        }

        // TODO(multidisplay): Update Dp to that of display stack is on.
        final float density = serviceConfig.densityDpi * DisplayMetrics.DENSITY_DEFAULT_SCALE;
        mOverrideConfig.screenWidthDp =
                Math.min((int)(mBounds.width() / density), serviceConfig.screenWidthDp);
        mOverrideConfig.screenHeightDp =
                Math.min((int)(mBounds.height() / density), serviceConfig.screenHeightDp);
        mOverrideConfig.smallestScreenWidthDp =
                Math.min(mOverrideConfig.screenWidthDp, mOverrideConfig.screenHeightDp);
        mOverrideConfig.orientation =
                (mOverrideConfig.screenWidthDp <= mOverrideConfig.screenHeightDp)
                        ? Configuration.ORIENTATION_PORTRAIT : Configuration.ORIENTATION_LANDSCAPE;
    }

    void updateDisplayInfo() {
        if (mFullscreen) {
            setBounds(null);
        } else if (mDisplayContent != null) {
            final int newRotation = mDisplayContent.getDisplayInfo().rotation;
            if (mRotation == newRotation) {
                return;
            }

            // Device rotation changed. We don't want the stack to move around on the screen when
            // this happens, so update the stack bounds so it stays in the same place.
            final int rotationDelta = DisplayContent.deltaRotation(mRotation, newRotation);
            mDisplayContent.getLogicalDisplayRect(mTmpRect);
            switch (rotationDelta) {
                case Surface.ROTATION_0:
                    mTmpRect2.set(mBounds);
                    break;
                case Surface.ROTATION_90:
                    mTmpRect2.top = mTmpRect.bottom - mBounds.right;
                    mTmpRect2.left = mBounds.top;
                    mTmpRect2.right = mTmpRect2.left + mBounds.height();
                    mTmpRect2.bottom = mTmpRect2.top + mBounds.width();
                    break;
                case Surface.ROTATION_180:
                    mTmpRect2.top = mTmpRect.bottom - mBounds.bottom;
                    mTmpRect2.left = mTmpRect.right - mBounds.right;
                    mTmpRect2.right = mTmpRect2.left + mBounds.width();
                    mTmpRect2.bottom = mTmpRect2.top + mBounds.height();
                    break;
                case Surface.ROTATION_270:
                    mTmpRect2.top = mBounds.left;
                    mTmpRect2.left = mTmpRect.right - mBounds.bottom;
                    mTmpRect2.right = mTmpRect2.left + mBounds.height();
                    mTmpRect2.bottom = mTmpRect2.top + mBounds.width();
                    break;
            }
            setBounds(mTmpRect2);
        }
    }

    boolean isFullscreen() {
        return mFullscreen;
    }

    /** Forces the stack to fullscreen if input is true, else un-forces the stack from fullscreen.
     * Returns true if something happened.
     */
    boolean forceFullscreen(boolean forceFullscreen) {
        if (mForceFullscreen == forceFullscreen) {
            return false;
        }
        mForceFullscreen = forceFullscreen;
        if (forceFullscreen) {
            if (mFullscreen) {
                return false;
            }
            mPreForceFullscreenBounds.set(mBounds);
            return setBounds(null);
        } else {
            if (!mFullscreen || mPreForceFullscreenBounds.isEmpty()) {
                return false;
            }
            return setBounds(mPreForceFullscreenBounds);
        }
    }

    boolean isAnimating() {
        for (int taskNdx = mTasks.size() - 1; taskNdx >= 0; --taskNdx) {
            final ArrayList<AppWindowToken> activities = mTasks.get(taskNdx).mAppTokens;
            for (int activityNdx = activities.size() - 1; activityNdx >= 0; --activityNdx) {
                final ArrayList<WindowState> windows = activities.get(activityNdx).allAppWindows;
                for (int winNdx = windows.size() - 1; winNdx >= 0; --winNdx) {
                    final WindowStateAnimator winAnimator = windows.get(winNdx).mWinAnimator;
                    if (winAnimator.isAnimating() || winAnimator.mWin.mExiting) {
                        return true;
                    }
                }
            }
        }
        return false;
    }

    void addTask(Task task, boolean toTop) {
        addTask(task, toTop, task.showForAllUsers());
    }

    /**
     * Put a Task in this stack. Used for adding and moving.
     * @param task The task to add.
     * @param toTop Whether to add it to the top or bottom.
     * @param showForAllUsers Whether to show the task regardless of the current user.
     */
    void addTask(Task task, boolean toTop, boolean showForAllUsers) {
        int stackNdx;
        if (!toTop) {
            stackNdx = 0;
        } else {
            stackNdx = mTasks.size();
            if (!showForAllUsers && !mService.isCurrentProfileLocked(task.mUserId)) {
                // Place the task below all current user tasks.
                while (--stackNdx >= 0) {
                    final Task tmpTask = mTasks.get(stackNdx);
                    if (!tmpTask.showForAllUsers()
                            || !mService.isCurrentProfileLocked(tmpTask.mUserId)) {
                        break;
                    }
                }
                // Put it above first non-current user task.
                ++stackNdx;
            }
        }
        if (DEBUG_TASK_MOVEMENT) Slog.d(TAG, "addTask: task=" + task + " toTop=" + toTop
                + " pos=" + stackNdx);
        mTasks.add(stackNdx, task);

        task.mStack = this;
        if (toTop) {
            mDisplayContent.moveStack(this, true);
        }
        EventLog.writeEvent(EventLogTags.WM_TASK_MOVED, task.mTaskId, toTop ? 1 : 0, stackNdx);
    }

    void moveTaskToTop(Task task) {
        if (DEBUG_TASK_MOVEMENT) Slog.d(TAG, "moveTaskToTop: task=" + task + " Callers="
                + Debug.getCallers(6));
        mTasks.remove(task);
        addTask(task, true);
    }

    void moveTaskToBottom(Task task) {
        if (DEBUG_TASK_MOVEMENT) Slog.d(TAG, "moveTaskToBottom: task=" + task);
        mTasks.remove(task);
        addTask(task, false);
    }

    /**
     * Delete a Task from this stack. If it is the last Task in the stack, move this stack to the
     * back.
     * @param task The Task to delete.
     */
    void removeTask(Task task) {
        if (DEBUG_TASK_MOVEMENT) Slog.d(TAG, "removeTask: task=" + task);
        mTasks.remove(task);
        if (mDisplayContent != null) {
            if (mTasks.isEmpty()) {
                mDisplayContent.moveStack(this, false);
            }
            mDisplayContent.layoutNeeded = true;
        }
        for (int appNdx = mExitingAppTokens.size() - 1; appNdx >= 0; --appNdx) {
            final AppWindowToken wtoken = mExitingAppTokens.get(appNdx);
            if (wtoken.mTask == task) {
                wtoken.mIsExiting = false;
                mExitingAppTokens.remove(appNdx);
            }
        }
    }

    void attachDisplayContent(DisplayContent displayContent) {
        if (mDisplayContent != null) {
            throw new IllegalStateException("attachDisplayContent: Already attached");
        }

        mDisplayContent = displayContent;
        mDimLayer = new DimLayer(mService, this, displayContent);
        mAnimationBackgroundSurface = new DimLayer(mService, this, displayContent);
        mBlurLayer = new BlurLayer(mService, this, displayContent);
        updateDisplayInfo();
    }

    void detachDisplay() {
        EventLog.writeEvent(EventLogTags.WM_STACK_REMOVED, mStackId);

        boolean doAnotherLayoutPass = false;
        for (int taskNdx = mTasks.size() - 1; taskNdx >= 0; --taskNdx) {
            final AppTokenList appWindowTokens = mTasks.get(taskNdx).mAppTokens;
            for (int appNdx = appWindowTokens.size() - 1; appNdx >= 0; --appNdx) {
                final WindowList appWindows = appWindowTokens.get(appNdx).allAppWindows;
                for (int winNdx = appWindows.size() - 1; winNdx >= 0; --winNdx) {
                    // We are in the middle of changing the state of displays/stacks/tasks. We need
                    // to finish that, before we let layout interfere with it.
                    mService.removeWindowInnerLocked(appWindows.get(winNdx),
                            false /* performLayout */);
                    doAnotherLayoutPass = true;
                }
            }
        }
        if (doAnotherLayoutPass) {
            mService.requestTraversalLocked();
        }
        close();
    }

    void resetAnimationBackgroundAnimator() {
        mAnimationBackgroundAnimator = null;
        mAnimationBackgroundSurface.hide();
    }

    private long getBlurBehindFadeDuration(long duration) {
        return getDimBehindFadeDuration(duration);
    }

    private long getDimBehindFadeDuration(long duration) {
        TypedValue tv = new TypedValue();
        mService.mContext.getResources().getValue(
                com.android.internal.R.fraction.config_dimBehindFadeDuration, tv, true);
        if (tv.type == TypedValue.TYPE_FRACTION) {
            duration = (long)tv.getFraction(duration, duration);
        } else if (tv.type >= TypedValue.TYPE_FIRST_INT && tv.type <= TypedValue.TYPE_LAST_INT) {
            duration = tv.data;
        }
        return duration;
    }

    boolean animateDimLayers() {
        final int dimLayer;
        final float dimAmount;
        if (mDimWinAnimator == null) {
            dimLayer = mDimLayer.getLayer();
            dimAmount = 0;
        } else {
            dimLayer = mDimWinAnimator.mAnimLayer - WindowManagerService.LAYER_OFFSET_DIM;
            dimAmount = mDimWinAnimator.mWin.mAttrs.dimAmount;
        }
        final float targetAlpha = mDimLayer.getTargetAlpha();
        if (targetAlpha != dimAmount) {
            if (mDimWinAnimator == null) {
                mDimLayer.hide(DEFAULT_DIM_DURATION);
            } else {
                long duration = (mDimWinAnimator.mAnimating && mDimWinAnimator.mAnimation != null)
                        ? mDimWinAnimator.mAnimation.computeDurationHint()
                        : DEFAULT_DIM_DURATION;
                if (targetAlpha > dimAmount) {
                    duration = getDimBehindFadeDuration(duration);
                }
                mDimLayer.show(dimLayer, dimAmount, duration);
            }
        } else if (mDimLayer.getLayer() != dimLayer) {
            mDimLayer.setLayer(dimLayer);
        }
        if (mDimLayer.isAnimating()) {
            if (!mService.okToDisplay()) {
                // Jump to the end of the animation.
                mDimLayer.show();
            } else {
                return mDimLayer.stepAnimation();
            }
        }
        return false;
    }

    void resetDimmingTag() {
        mDimmingTag = false;
    }

    void setDimmingTag() {
        mDimmingTag = true;
    }

    boolean testDimmingTag() {
        return mDimmingTag;
    }

    boolean isDimming() {
        return mDimLayer.isDimming();
    }

    boolean isDimming(WindowStateAnimator winAnimator) {
        return mDimWinAnimator == winAnimator && mDimLayer.isDimming();
    }

    void startDimmingIfNeeded(WindowStateAnimator newWinAnimator) {
        // Only set dim params on the highest dimmed layer.
        // Don't turn on for an unshown surface, or for any layer but the highest dimmed layer.
        if (newWinAnimator.mSurfaceShown && (mDimWinAnimator == null
                || !mDimWinAnimator.mSurfaceShown
                || mDimWinAnimator.mAnimLayer < newWinAnimator.mAnimLayer)) {
            mDimWinAnimator = newWinAnimator;
            if (mDimWinAnimator.mWin.mAppToken == null
                    && !mFullscreen && mDisplayContent != null) {
                // Dim should cover the entire screen for system windows.
                mDisplayContent.getLogicalDisplayRect(mTmpRect);
                mDimLayer.setBounds(mTmpRect);
            }
        }
    }

    void stopDimmingIfNeeded() {
        if (!mDimmingTag && isDimming()) {
            mDimWinAnimator = null;
            mDimLayer.setBounds(mBounds);
        }
    }

    void setAnimationBackground(WindowStateAnimator winAnimator, int color) {
        int animLayer = winAnimator.mAnimLayer;
        if (mAnimationBackgroundAnimator == null
                || animLayer < mAnimationBackgroundAnimator.mAnimLayer) {
            mAnimationBackgroundAnimator = winAnimator;
            animLayer = mService.adjustAnimationBackground(winAnimator);
            mAnimationBackgroundSurface.show(animLayer - WindowManagerService.LAYER_OFFSET_DIM,
                    ((color >> 24) & 0xff) / 255f, 0);
        }
    }

    boolean animateBlurLayers() {
        boolean result = false;
        final int blurLayer;
        final float blurAmount;
        if (mBlurWinAnimator == null) {
            blurLayer = mBlurLayer.getLayer();
            blurAmount = 0;
        } else {
            blurLayer = mBlurWinAnimator.mAnimLayer - WindowManagerService.LAYER_OFFSET_BLUR;
            blurAmount = mBlurWinAnimator.mWin.mAttrs.blurAmount;
        }
        final float targetBlur = mBlurLayer.getTargetBlur();
        if (targetBlur != blurAmount) {
            if (mBlurWinAnimator == null) {
                mBlurLayer.hide(DEFAULT_BLUR_DURATION);
            } else {
                long duration = (mBlurWinAnimator.mAnimating && mBlurWinAnimator.mAnimation != null)
                        ? mBlurWinAnimator.mAnimation.computeDurationHint()
                        : DEFAULT_BLUR_DURATION;
                if (targetBlur > blurAmount) {
                    duration = getBlurBehindFadeDuration(duration);
                }
                if (duration > DEFAULT_BLUR_DURATION)
                    duration = DEFAULT_BLUR_DURATION;
                mBlurLayer.show(blurLayer, blurAmount, duration);
            }
        } else if (mBlurLayer.getLayer() != blurLayer) {
            mBlurLayer.setLayer(blurLayer);
        }
        if (mBlurLayer.isAnimating()) {
            if (!mService.okToDisplay()) {
                // Jump to the end of the animation.
                mBlurLayer.show();
            } else {
                result = mBlurLayer.stepAnimation();
            }
        }
        return result;
    }

    void resetBlurringTag() {
        mBlurringTag = false;
    }

    void setBlurringTag() {
        mBlurringTag = true;
    }

    boolean testBlurringTag() {
        return mBlurringTag;
    }

    boolean isBlurring() {
        return mBlurLayer.isBlurring();
    }

    boolean isBlurring(WindowStateAnimator winAnimator) {
        return mBlurWinAnimator == winAnimator && mBlurLayer.isBlurring();
    }

    void stopBlurringIfNeeded() {
        if (!mBlurringTag && isBlurring()) {
            mBlurWinAnimator = null;
        }
    }

    void startBlurringIfNeeded(WindowStateAnimator newWinAnimator) {
        final WindowStateAnimator existingBlurWinAnimator = mBlurWinAnimator;
        // Don't turn on for an unshown surface, or for any layer but the highest blur layer.
        if (newWinAnimator.mSurfaceShown && (existingBlurWinAnimator == null
                || !existingBlurWinAnimator.mSurfaceShown
                || existingBlurWinAnimator.mAnimLayer < newWinAnimator.mAnimLayer)) {
            mBlurWinAnimator = newWinAnimator;
        }
    }

    void switchUser() {
        int top = mTasks.size();
        for (int taskNdx = 0; taskNdx < top; ++taskNdx) {
            Task task = mTasks.get(taskNdx);
            if (mService.isCurrentProfileLocked(task.mUserId) || task.showForAllUsers()) {
                mTasks.remove(taskNdx);
                mTasks.add(task);
                --top;
            }
        }
    }

    void close() {
        if (mAnimationBackgroundSurface != null) {
            mAnimationBackgroundSurface.destroySurface();
            mAnimationBackgroundSurface = null;
        }
        if (mDimLayer != null) {
            mDimLayer.destroySurface();
            mDimLayer = null;
        }
        if (mBlurLayer != null) {
            mBlurLayer.destroySurface();
            mBlurLayer = null;
        }
        mDisplayContent = null;
    }

    public void dump(String prefix, PrintWriter pw) {
        pw.print(prefix); pw.print("mStackId="); pw.println(mStackId);
        pw.print(prefix); pw.print("mDeferDetach="); pw.println(mDeferDetach);
        for (int taskNdx = 0; taskNdx < mTasks.size(); ++taskNdx) {
            pw.print(prefix); pw.println(mTasks.get(taskNdx));
        }
        if (mAnimationBackgroundSurface.isDimming()) {
            pw.print(prefix); pw.println("mWindowAnimationBackgroundSurface:");
            mAnimationBackgroundSurface.printTo(prefix + "  ", pw);
        }
        if (mDimLayer.isDimming()) {
            pw.print(prefix); pw.println("mDimLayer:");
            mDimLayer.printTo(prefix + " ", pw);
            pw.print(prefix); pw.print("mDimWinAnimator="); pw.println(mDimWinAnimator);
        }
        if (mBlurLayer.isBlurring()) {
            pw.print(prefix); pw.println("mBlurLayer:");
            mBlurLayer.printTo(prefix, pw);
            pw.print(prefix); pw.print("mBlurWinAnimator="); pw.println(mBlurWinAnimator);
        }
        if (!mExitingAppTokens.isEmpty()) {
            pw.println();
            pw.println("  Exiting application tokens:");
            for (int i=mExitingAppTokens.size()-1; i>=0; i--) {
                WindowToken token = mExitingAppTokens.get(i);
                pw.print("  Exiting App #"); pw.print(i);
                pw.print(' '); pw.print(token);
                pw.println(':');
                token.dump(pw, "    ");
            }
        }
    }

    @Override
    public String toString() {
        return "{stackId=" + mStackId + " tasks=" + mTasks + "}";
    }
}