无论是系统中窗口的动画,还是应用中某一个View的动画,它们的原理都是一样的。当一个窗口打开的时候,为了看起来更缓和一点,系统都会给每一个Activity窗口添加一个动画,关于动画的部分,我所想写的有四点。第一、动画有哪些类型;第二动画是怎么设置的,由于窗口动画和过度动画(Activity窗口动画)是不一样的,就需要分开讲,在小米手机上,可以去开发者选项中将窗口动画的播放速度降慢5倍或者10倍,可以清楚的看到动画的过程。第三,动画设置完成之后,怎么触发垂直刷新信号一帧帧显示的,由于一个窗口可能存在多个动画,比如转屏动画、过度动画、窗口动画,自身动画等等,最终交给SurfaceFlinger绘制显示的时候,需要合成为一个动画,所以在谈一下动画的合成;第四,简单总结应用动画,用一个贝塞尔曲线绘制直播间点赞效果的例子讲解一下,总结而言,系统中的动画和应用中的动画原理是一样的,这篇文章是站在系统的角度上,搞清楚动画的原理,本文基于Android7.0源码。
####一、动画类型
在Apptransition.java中定义了很多动画的类型,每个类型以一个int值来表示。
动画类型 | 值 | 含义 |
---|---|---|
TRANSIT_UNSET | -1 | 初始值,尚未设定 |
TRANSIT_NONE | 0 | 没有动画 |
TRANSIT_ACTIVITY_OPEN | 6 | 在同一task中在最顶端打开一个窗口 |
TRANSIT_ACTIVITY_CLOSE | 7 | 关闭当前活动窗口,恢复同一个task中的上一个窗口 |
TRANSIT_TASK_OPEN | 8 | 新建任务并创建窗口 |
TRANSIT_TASK_CLOSE | 9 | 关闭当前活动窗口,回到上一个任务 |
TRANSIT_TASK_TO_FRONT | 10 | 将任务移至最顶 |
TRANSIT_TASK_TO_BACK | 11 | 将当前任务移至最末 |
TRANSIT_WALLPAPER_CLOSE | 12 | 关闭到无墙纸的应用 |
TRANSIT_WALLPAPER_OPEN | 13 | 启动墙纸应用 |
TRANSIT_WALLPAPER_INTRA_OPEN | 14 | 有墙纸打开 |
TRANSIT_WALLPAPER_INTRA_CLOSE | 15 | 有墙纸关闭 |
默认是没有动画,即类型是TRANSIT_UNSET,拿Activity的启动来举例子,比如当一个Activity打开的时候,那么系统就会设置一个TRANSIT_ACTIVITY_OPEN的动画,如果你startActivity组件的时候,Intent对象带有FLAG_ACTIVITY_NO_ANIMATION这样的flag,那么系统就会给你设置一个TRANSIT_NONE,表示没有动画,不需要动画,如果你指定了lauchMode,跨Task栈新起了一个Actiivty,那么就会设置一个TRANSIT_TASK_OPEN类型,表示新建任务并创建窗口时候要用的动画,同理当Activity的关闭的时候,也类似,总之根据不同的case,设置不同的类型,后面根据这个设置好的类型,加载不同的动画。
####二、动画设置
了解了动画类型了,我们看一下Activity切换的时候,动画是怎么设置的,先简单看一下Activity的切换。
#####1、Activiy切换
什么是Activity的切换呢?
前一个Activity从resume状态变成pause状态,后一个Activity进入到resume状态,将前一个resume状态的窗口设置成不可见,后一个窗口设置成可见。
切换的步骤
首先梳理一下prepareAppTransition方法。设置什么样的切换操作,其实由Activity的行为决定。
- frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
- @Override
- public void prepareAppTransition(int transit, boolean alwaysKeepCurrent) {
- if (!checkCallingPermission(android.Manifest.permission.MANAGE_APP_TOKENS,
- "prepareAppTransition()")) {
- throw new SecurityException("Requires MANAGE_APP_TOKENS permission");
- }
- synchronized(mWindowMap) {
- boolean prepared = mAppTransition.prepareAppTransitionLocked(
- transit, alwaysKeepCurrent);
- //prepared为ture,说明已经被成功设置了切换操作,但是当前冻屏、熄屏、Display没有准备好的情况下,
- //设置mSkipAppTransitionAnimation等于true,表示要跳过这切换操作对应动画的执行。
- if (prepared && okToDisplay()) {
- mSkipAppTransitionAnimation = false;
- }
- }
- }
- frameworks / base / services / core / java / com / android / server / wm / AppTransition.java
- boolean prepareAppTransitionLocked(int transit, boolean alwaysKeepCurrent) {.....
- //isTransitionSet()表示已经设置了切换操作类型
- if (!isTransitionSet() || mNextAppTransition == TRANSIT_NONE) {
- setAppTransition(transit);
- } else if (!alwaysKeepCurrent) {
- //alwaysKeepCurrent若等于true,表示要维持上次设置的切换类型,本次新设置的不能覆盖它
- if (transit == TRANSIT_TASK_OPEN && isTransitionEqual(TRANSIT_TASK_CLOSE)) {
- // Opening a new task always supersedes a close for the anim.
- setAppTransition(transit);
- } else if (transit == TRANSIT_ACTIVITY_OPEN && isTransitionEqual(TRANSIT_ACTIVITY_CLOSE)) {
- // Opening a new activity always supersedes a close for the anim.
- setAppTransition(transit);
- }
- }
- boolean prepared = prepare();
- if (isTransitionSet()) {
- //发送一个5秒的超时消息给WMS运行的线程(android.display线程),表示要在5秒时间类完成设置的切换操作。
- mService.mH.removeMessages(H.APP_TRANSITION_TIMEOUT);
- mService.mH.sendEmptyMessageDelayed(H.APP_TRANSITION_TIMEOUT, APP_TRANSITION_TIMEOUT_MS);
- }
- return prepared;
- }
如果transit == TRANSIT_TASK_OPEN 并且isTransitionEqual(TRANSIT_TASK_CLOSE)返回true,表示上次(之前)给Activity设置的切换操作是TRANSIT_TASK_CLOSE,那么可以调用setAppTransition,因为打开的动画要比关闭的动画优先级要高。
如果transit == TRANSIT_ACTIVITY_OPEN 并且isTransitionEqual(TRANSIT_ACTIVITY_CLOSE)返回true,表示上次(之前)给Activity设置的切换操作是TRANSIT_ACTIVITY_CLOSE,那么可以调用setAppTransition,因为打开的动画要比关闭的动画优先级要高。
- frameworks/base/services/core/java/com/android/server/wm/AppTransition.java
- private void setAppTransition(int transit) {
- mNextAppTransition = transit;
- setLastAppTransition(TRANSIT_UNSET, null, null);
- }
setAppTransition执行过后,并且前一个激活的Activity组件进入到Paused状态了,并且客户端进程已经启动了,这个时候ActivityManagerService服务就会调用ActivityStack类的成员函数realStartActivityLocked来将正在启动的Activity组件加载起来,并且将它的状态设置为Resumed,首先看一下setAppVisibility,将窗口可见性的设置。
- frameworks / base / services / core / java / com / android / server / wm / WindowManagerService.java
- @Override public void setAppVisibility(IBinder token, boolean visible) {.....AppWindowToken wtoken;
- synchronized(mWindowMap) {
- //通过ActivityRecord:Token找到AppWindowToken,即找到这个token对应的Activity窗口
- wtoken = findAppWindowToken(token);
- if (wtoken == null) {
- Slog.w(TAG_WM, "Attempted to set visibility of non-existing app token: " + token);
- return;
- }.....
- //mOpeningApps是WMS的成员,里面存放所有打开的窗口的AppWindowToken,首先移除,后面根据visible添加
- mOpeningApps.remove(wtoken);
- //mClosingApps是WMS的成员,里面存放所有关闭的窗口的AppWindowToken,首先移除,后面根据visible添加
- mClosingApps.remove(wtoken);
- //表示等待着去显示
- wtoken.waitingToShow = false;
- wtoken.hiddenRequested = !visible;
- if (!visible) {
- // If the app is dead while it was visible, we kept its dead window on screen.
- // Now that the app is going invisible, we can remove it. It will be restarted
- // if made visible again.
- wtoken.removeAllDeadWindows();
- wtoken.setVisibleBeforeClientHidden();
- } else if (visible) {
- if (!mAppTransition.isTransitionSet() && mAppTransition.isReady()) {
- // Add the app mOpeningApps if transition is unset but ready. This means
- // we're doing a screen freeze, and the unfreeze will wait for all opening
- // apps to be ready.
- mOpeningApps.add(wtoken);
- }
- wtoken.startingMoved = false;
- // If the token is currently hidden (should be the common case), or has been
- // stopped, then we need to set up to wait for its windows to be ready.
- if (wtoken.hidden || wtoken.mAppStopped) {
- wtoken.clearAllDrawn();
- // If the app was already visible, don't reset the waitingToShow state.
- //如果hidden的值等于false,说明Activity组件当前是不可见的。又由于上面visible为true,表示Activity将要被设置成可见的,
- //因此,这时候就需要将AppWindowToken对象wtoken的成员变量waitingToShow的值设置为true。
- if (wtoken.hidden) {
- wtoken.waitingToShow = true;
- }
- if (wtoken.clientHidden) {
- // In the case where we are making an app visible
- // but holding off for a transition, we still need
- // to tell the client to make its windows visible so
- // they get drawn. Otherwise, we will wait on
- // performing the transition until all windows have
- // been drawn, they never will be, and we are sad.
- wtoken.clientHidden = false;
- //通知应用程序进程将参数token所描述的Activity组件设置为true
- wtoken.sendAppVisibilityToClients();
- }
- }
- wtoken.requestUpdateWallpaperIfNeeded();
- if (DEBUG_ADD_REMOVE) Slog.v(TAG_WM, "No longer Stopped: " + wtoken);
- wtoken.mAppStopped = false;
- }
- //这个if分之在动画设置完成并且屏幕不冻屏,亮屏、Display OK的情况下才会走
- if (okToDisplay() && mAppTransition.isTransitionSet()) {
- if (wtoken.mAppAnimator.usingTransferredAnimation && wtoken.mAppAnimator.animation == null) {
- Slog.wtf(TAG_WM, "Will NOT set dummy animation on: " + wtoken + ", using null transfered animation!");
- }
- if (!wtoken.mAppAnimator.usingTransferredAnimation && (!wtoken.startingDisplayed || mSkipAppTransitionAnimation)) {
- if (DEBUG_APP_TRANSITIONS) Slog.v(TAG_WM, "Setting dummy animation on: " + wtoken);
- //设置哑动画,可以理解是一个站位的作用,后面会对它设置真正的动画
- wtoken.mAppAnimator.setDummyAnimation();
- }
- wtoken.inPendingTransaction = true;
- if (visible) {
- //可见,把wtoken加入到mOpeningApps
- mOpeningApps.add(wtoken);
- wtoken.mEnteringAnimation = true;
- } else {
- //不可见,把wtoken加入到mClosingApps
- mClosingApps.add(wtoken);
- wtoken.mEnteringAnimation = false;
- }
- if (mAppTransition.getAppTransition() == AppTransition.TRANSIT_TASK_OPEN_BEHIND) {
- // We're launchingBehind, add the launching activity to mOpeningApps.
- final WindowState win = findFocusedWindowLocked(getDefaultDisplayContentLocked());
- if (win != null) {
- final AppWindowToken focusedToken = win.mAppToken;
- if (focusedToken != null) {
- focusedToken.hidden = true;
- mOpeningApps.add(focusedToken);
- }
- }
- }
- return;
- }
- final long origId = Binder.clearCallingIdentity();
- wtoken.inPendingTransaction = false;
- //将参数token所描述的Activity组件的可见性设置为参数visible所描述的值;
- setTokenVisibilityLocked(wtoken, null, visible, AppTransition.TRANSIT_UNSET, true, wtoken.voiceInteraction);
- //向WMS服务上报参数token所描述的Activity组件的可见性
- wtoken.updateReportedVisibilityLocked();
- Binder.restoreCallingIdentity(origId);
- }
- }
这个方法变量比较多,要全部弄明白,还是要花费一些功夫的。setAppVisibility设置好之后,就可以通知客户端启动APP进程了,(所以这样看来,当一个Activity的实例还不存在的时候,它的窗口的token就已经被确定了)接着往下走,completeResumeLocked方法主要是从上下到检查哪些Activity组件是需要设置为可见的,哪些Activity组件是需要设置为不可见的,找到栈顶部第一个全屏显示的Activity组件,调用setAppVisibility设置为true,这个全屏显示Activity组件下面的所有Activity组件的可见性设置为false。
最后通知WindowManagerService服务调用executeAppTransition方法执行前面所准备的切换操作,执行这个切换操作跟Activity窗口动画(过度动画)有关系,现在就开始第二节内容。
#####2、过度动画设置
粗略的看一共19个步骤,前面prepareAppTransition设置切换操作和sendAppVisibility方法设置哪个Activity要隐藏,哪个Activity的要显示,已经解释过了,现在从sendAppVisibilityToClient开始。sendAppVisibilityToClient/dispatchAppVibility 这两个函数就是通知上层应用窗口可见性发生变化。如果下一个Activity是冷启动,那么这个函数并不能通知下一个Activity的窗口变为可见,因为此时该函数调用时,下一个Activity的窗口还没加到到WMS中来,Activity的窗口添加是Activity 的onResume方法中添加的。然后到第四步finishDrawingWindow下一个被Resume起来后,添加窗口、measure、layout、draw等一系列操作完成后便会调用WMS.finishDrawingWindow()来通知WMS,该窗口已经绘制好了,可以开始做动画了。WMS.finishDrawingWindow()会调用WindowStateAnimator.finishDrawingLocked()更新窗口状态mDrawState为COMMIT_DRAW_PENDING。其次WindowSurfacePlacer的requestTraversal方法,WindowSurfacePlacer的requestTraversal方法只是向WMS的主线程发送了一个DO_TRAVERSAL消息,WMS收到这个消息后,performSurfacePlacement方法就会执行。
- frameworks / base / services / core / java / com / android / server / wm / WindowSurfacePlacer.java final void performSurfacePlacement() {
- if (mDeferDepth > 0) {
- return;
- }
- int loopCount = 6;
- do {
- mTraversalScheduled = false;
- performSurfacePlacementLoop();
- mService.mH.removeMessages(DO_TRAVERSAL);
- loopCount--;
- } while ( mTraversalScheduled && loopCount > 0 );
- mWallpaperActionPending = false;
- }
序列图中performSurfacePlacement、performSurfacePlacementLoop、performSurfacePlacementInner三个方法都是跟渲染相关的。performSurfacePlacement中调用了performSurfacePlacementLoop,performSurfacePlacementLoop中调用了performSurfacePlacementInner。(todolist:梳理performSurfacePlacement方法)
第十步commitFinishDrawingLocked是applySurfaceChangesTransaction方法调用进来的,该函数将窗口状态为COMMIT_DRAW_PENDING或READY_TO_SHOW的窗口,全部更新到READY_TO_SHOW状态
第十一步updateAllDrawnLocked函数更新AppWindowToken.allDrawn值。只有属于该AppWindowToken的所有窗口都是绘制完成状态(一般情况下只有一个窗口,有时候会有父窗口、子窗口,这时属于该AppWindowToken的窗口数量就不止一个了),AppWindowToken.allDrawn才会置为true。AppWindowToken.allDrawn为true才会使得第十步中的WMS.handleAppTransitionReadyLocked()完整的执行。
第十二步handleAppTransitionReadyLocked主要做了以下几件事情。
- private int handleAppTransitionReadyLocked(WindowList windows) {
- //获取系统中所有打开的activity数量
- int appsCount = mService.mOpeningApps.size();
- //transitionGoodToGo会判断多种case情况下,不用执行动画的情况,
- //比如正在做转屏动画,mOpeningApps中任何一个allDrawn不等于true等
- if (!transitionGoodToGo(appsCount)) {
- return 0;
- }
- Trace.traceBegin(Trace.TRACE_TAG_WINDOW_MANAGER, "AppTransitionReady");
- if (DEBUG_APP_TRANSITIONS) Slog.v(TAG, "**** GOOD TO GO");
- //获取前面设置好的切换操作
- int transit = mService.mAppTransition.getAppTransition();
- //如果因为动画没有成功设置好,或者因为冻屏等原因,导致的WMS中mSkipAppTransitionAnimation为true的话,切换操作类型设置为TRANSIT_UNSET
- if (mService.mSkipAppTransitionAnimation) {
- transit = AppTransition.TRANSIT_UNSET;
- }
- mService.mSkipAppTransitionAnimation = false;
- mService.mNoAnimationNotifyOnTransitionFinished.clear();
- //这个时候可以移除prepareAppTransition中设置的超时消息
- mService.mH.removeMessages(H.APP_TRANSITION_TIMEOUT);
- //重新进行窗口的排序,防止乱序
- mService.rebuildAppWindowListLocked();
- mWallpaperMayChange = false;
- // The top-most window will supply the layout params,
- // and we will determine it below.
- //用来保存窗口参数
- LayoutParams animLp = null;
- int bestAnimLayer = -1;
- boolean fullscreenAnim = false;
- //是否有语音交互
- boolean voiceInteraction = false;
- int i;
- for (i = 0; i < appsCount; i++) {
- final AppWindowToken wtoken = mService.mOpeningApps.valueAt(i);
- // Clearing the mAnimatingExit flag before entering animation. It's set to
- // true if app window is removed, or window relayout to invisible.
- // This also affects window visibility. We need to clear it *before*
- // maybeUpdateTransitToWallpaper() as the transition selection depends on
- // wallpaper target visibility.
- wtoken.clearAnimatingFlags();
- }
- // Adjust wallpaper before we pull the lower/upper target, since pending changes
- // (like the clearAnimatingFlags() above) might affect wallpaper target result.
- final DisplayContent displayContent = mService.getDefaultDisplayContentLocked();
- if ((displayContent.pendingLayoutChanges & FINISH_LAYOUT_REDO_WALLPAPER) != 0 && mWallpaperControllerLocked.adjustWallpaperWindows()) {
- //上面执行了clearAnimatingFlags,会影响Z-order.这里重新调整一下
- mService.mLayersController.assignLayersLocked(windows);
- displayContent.layoutNeeded = true;
- }
- //在调整壁纸窗口在窗口堆栈的位置的时候,如果碰到系统在执行两个Activity组件的切换操作,
- //并且这两个Activity组件都需要显示壁纸,
- //那么Z轴位置较低的窗口就会lowerWallpaperTarget中,
- //而Z轴位置较高的窗口就会保存在upperWallpaperTarget中。
- final WindowState lowerWallpaperTarget = mWallpaperControllerLocked.getLowerWallpaperTarget();
- final WindowState upperWallpaperTarget = mWallpaperControllerLocked.getUpperWallpaperTarget();
- boolean openingAppHasWallpaper = false;
- boolean closingAppHasWallpaper = false;
- final AppWindowToken lowerWallpaperAppToken;
- final AppWindowToken upperWallpaperAppToken;
- if (lowerWallpaperTarget == null) {
- lowerWallpaperAppToken = upperWallpaperAppToken = null;
- } else {
- lowerWallpaperAppToken = lowerWallpaperTarget.mAppToken;
- upperWallpaperAppToken = upperWallpaperTarget.mAppToken;
- }
- // Do a first pass through the tokens for two
- // things:
- // (1) Determine if both the closing and opening
- // app token sets are wallpaper targets, in which
- // case special animations are needed
- // (since the wallpaper needs to stay static
- // behind them).
- // (2) Find the layout params of the top-most
- // application window in the tokens, which is
- // what will control the animation theme.
- //获取关闭的activiy数量
- final int closingAppsCount = mService.mClosingApps.size();
- //获取打开的activiy数量
- appsCount = closingAppsCount + mService.mOpeningApps.size();
- //这段代码的for循环就是要从参与切换操作的Activity组件的窗口的WindowManager.LayoutParams对象中挑选出一个来创建切换动画
- //要求是主窗口,它是所有候选窗口中Z轴位置最高的
- for (i = 0; i < appsCount; i++) {
- final AppWindowToken wtoken;
- if (i < closingAppsCount) {
- wtoken = mService.mClosingApps.valueAt(i);
- if (wtoken == lowerWallpaperAppToken || wtoken == upperWallpaperAppToken) {
- //Activity关闭的时候,要显示墙纸窗口
- closingAppHasWallpaper = true;
- }
- } else {
- wtoken = mService.mOpeningApps.valueAt(i - closingAppsCount);
- if (wtoken == lowerWallpaperAppToken || wtoken == upperWallpaperAppToken) {
- //Activity打开的时候,要显示墙纸窗口
- openingAppHasWallpaper = true;
- }
- }
- voiceInteraction |= wtoken.voiceInteraction;
- //是否是全屏
- if (wtoken.appFullscreen) {
- //找到主窗口,类型为TYPE_BASE_APPLICATION或者TYPE_APPLICATION_STARTING类型的
- WindowState ws = wtoken.findMainWindow();
- if (ws != null) {
- animLp = ws.mAttrs;
- bestAnimLayer = ws.mLayer;
- fullscreenAnim = true;
- }
- } else if (!fullscreenAnim) {
- WindowState ws = wtoken.findMainWindow();
- if (ws != null) {
- if (ws.mLayer > bestAnimLayer) {
- animLp = ws.mAttrs;
- bestAnimLayer = ws.mLayer;
- }
- }
- }
- }
- //判断切换操作跟墙纸类型是否相关,调整窗口的类型(mayUpdateTransitionToWallpaper)
- transit = maybeUpdateTransitToWallpaper(transit, openingAppHasWallpaper, closingAppHasWallpaper, lowerWallpaperTarget, upperWallpaperTarget);
- // If all closing windows are obscured, then there is
- // no need to do an animation. This is the case, for
- // example, when this transition is being done behind
- // the lock screen.
- if (!mService.mPolicy.allowAppAnimationsLw()) {
- if (DEBUG_APP_TRANSITIONS) Slog.v(TAG, "Animations disallowed by keyguard or dream.");
- animLp = null;
- }
- processApplicationsAnimatingInPlace(transit);
- mTmpLayerAndToken.token = null;
- // MIUI ADD:
- mService.mAppTransition.updateAllowCustomAnimationIfNeeded(mService.mClosingApps);
- //处理关闭的Activity
- handleClosingApps(transit, animLp, voiceInteraction, mTmpLayerAndToken);
- final AppWindowToken topClosingApp = mTmpLayerAndToken.token;
- final int topClosingLayer = mTmpLayerAndToken.layer;
- //处理打开的Activity,下面会说
- final AppWindowToken topOpeningApp = handleOpeningApps(transit, animLp, voiceInteraction, topClosingLayer);
- mService.mAppTransition.setLastAppTransition(transit, topOpeningApp, topClosingApp);
- final AppWindowAnimator openingAppAnimator = (topOpeningApp == null) ? null: topOpeningApp.mAppAnimator;
- final AppWindowAnimator closingAppAnimator = (topClosingApp == null) ? null: topClosingApp.mAppAnimator;
- mService.mAppTransition.goodToGo(openingAppAnimator, closingAppAnimator, mService.mOpeningApps, mService.mClosingApps);
- mService.mAppTransition.postAnimationCallback();
- mService.mAppTransition.clear();
- mService.mOpeningApps.clear();
- mService.mClosingApps.clear();
- .....
- return FINISH_LAYOUT_REDO_LAYOUT | FINISH_LAYOUT_REDO_CONFIG;
- }
总体来说大致有八个步骤
第十三步handleOpeningApps这个函数用来设置APPWindowToken.hidden的可见性、设置Activity切换动画(如果参数transit==AppTransition.TRANSIT_UNSET,那就是会设置窗口动画,否则就会设置Activity切换动画),如果存在Activity切换动画或属于该Activity的窗口正在做窗口动画,那么返回值为true,handleOpeningApps中调用了setTokenVisibilityLocked方法。
- /frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
- boolean setTokenVisibilityLocked(AppWindowToken wtoken, WindowManager.LayoutParams lp,
- boolean visible, int transit, boolean performLayout, boolean isVoiceInteraction) {
- boolean delayed = false;
- if (wtoken.clientHidden == visible) {
- wtoken.clientHidden = !visible;
- //再次通知应用程序端设置窗口可见性
- wtoken.sendAppVisibilityToClients();
- }
- boolean visibilityChanged = false;
- if (wtoken.hidden == visible || (wtoken.hidden && wtoken.mIsExiting) ||
- (visible && wtoken.waitingForReplacement())) {
- boolean changed = false;
- boolean runningAppAnimation = false;
- if (transit != AppTransition.TRANSIT_UNSET) {
- if (wtoken.mAppAnimator.animation == AppWindowAnimator.sDummyAnimation) {
- //把前面的哑动画清空
- wtoken.mAppAnimator.setNullAnimation();
- }
- //创建动画
- if (applyAnimationLocked(wtoken, lp, transit, visible, isVoiceInteraction)) {
- delayed = runningAppAnimation = true;
- }
- WindowState window = wtoken.findMainWindow();
- if (window != null && mAccessibilityController != null
- && window.getDisplayId() == Display.DEFAULT_DISPLAY) {
- mAccessibilityController.onAppWindowTransitionLocked(window, transit);
- }
- changed = true;
- }
- .......
- }
- .......
- return delayed;
- }
创建动画是applyAnimationLocked方法干的事情。
- frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
- private boolean applyAnimationLocked(AppWindowToken atoken, WindowManager.LayoutParams lp,
- int transit, boolean enter, boolean isVoiceInteraction) {
- // Only apply an animation if the display isn't frozen. If it is
- // frozen, there is no reason to animate and it can cause strange
- // artifacts when we unfreeze the display if some different animation
- // is running.
- Trace.traceBegin(Trace.TRACE_TAG_WINDOW_MANAGER, "WM#applyAnimationLocked");
- if (okToDisplay()) {
- ....
- //传入各种参数,用AppTransition的loadAnimation创建一个动画
- Animation a = mAppTransition.loadAnimation(lp, transit, enter, mCurConfiguration.uiMode,
- mCurConfiguration.orientation, frame, displayFrame, insets, surfaceInsets,
- isVoiceInteraction, freeform, atoken.mTask.mTaskId, mIsInMultiWindowMode);
- ....
- if (a != null) {
- ....
- atoken.mAppAnimator.setAnimation(a, containingWidth, containingHeight,
- mAppTransition.canSkipFirstFrame(), mAppTransition.getAppStackClipMode());
- ....
- }
- } else {
- atoken.mAppAnimator.clearAnimation();
- }
- return atoken.mAppAnimator.animation != null;
- }
applyAnimationLocked内部实质上还是调用loadAnimation。
- frameworks/base/services/core/java/com/android/server/wm/AppTransition.java
- Animation loadAnimation(WindowManager.LayoutParams lp, int transit, boolean enter, int uiMode,
- int orientation, Rect frame, Rect displayFrame, Rect insets,
- @Nullable Rect surfaceInsets, boolean isVoiceInteraction, boolean freeform,
- int taskId, boolean isInMultiWindowMode) {
- if (transit == TRANSIT_WALLPAPER_OPEN && mNextAppTransitionType == NEXT_TRANSIT_TYPE_CUSTOM
- && !mAllowCustomAnimation) {
- mNextAppTransitionType = AppTransitionInjector.NEXT_TRANSIT_TYPE_BACK_HOME;
- }
- Animation a;
- if (isVoiceInteraction && (transit == TRANSIT_ACTIVITY_OPEN
- || transit == TRANSIT_TASK_OPEN
- || transit == TRANSIT_TASK_TO_FRONT)) {
- a = loadAnimationRes(lp, enter
- ? com.android.internal.R.anim.voice_activity_open_enter
- : com.android.internal.R.anim.voice_activity_open_exit);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation voice:"
- + " anim=" + a + " transit=" + appTransitionToString(transit)
- + " isEntrance=" + enter + " Callers=" + Debug.getCallers(3));
- } else if (isVoiceInteraction && (transit == TRANSIT_ACTIVITY_CLOSE
- || transit == TRANSIT_TASK_CLOSE
- || transit == TRANSIT_TASK_TO_BACK)) {
- a = loadAnimationRes(lp, enter
- ? com.android.internal.R.anim.voice_activity_close_enter
- : com.android.internal.R.anim.voice_activity_close_exit);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation voice:"
- + " anim=" + a + " transit=" + appTransitionToString(transit)
- + " isEntrance=" + enter + " Callers=" + Debug.getCallers(3));
- } else if (transit == TRANSIT_ACTIVITY_RELAUNCH) {
- a = createRelaunchAnimation(frame, insets);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a + " nextAppTransition=" + mNextAppTransition
- + " transit=" + appTransitionToString(transit)
- + " Callers=" + Debug.getCallers(3));
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_CUSTOM) {
- a = loadAnimationRes(mNextAppTransitionPackage, enter ?
- mNextAppTransitionEnter : mNextAppTransitionExit);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a + " nextAppTransition=ANIM_CUSTOM"
- + " transit=" + appTransitionToString(transit) + " isEntrance=" + enter
- + " Callers=" + Debug.getCallers(3));
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_CUSTOM_IN_PLACE) {
- a = loadAnimationRes(mNextAppTransitionPackage, mNextAppTransitionInPlace);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a + " nextAppTransition=ANIM_CUSTOM_IN_PLACE"
- + " transit=" + appTransitionToString(transit)
- + " Callers=" + Debug.getCallers(3));
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_CLIP_REVEAL) {
- a = createClipRevealAnimationLocked(transit, enter, frame, displayFrame);
- mLauncherAnimationRect.setEmpty();
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a + " nextAppTransition=ANIM_CLIP_REVEAL"
- + " transit=" + appTransitionToString(transit)
- + " Callers=" + Debug.getCallers(3));
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_SCALE_UP) {
- a = createScaleUpAnimationLocked(transit, enter, frame);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a + " nextAppTransition=ANIM_SCALE_UP"
- + " transit=" + appTransitionToString(transit) + " isEntrance=" + enter
- + " Callers=" + Debug.getCallers(3));
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_SCALE_UP ||
- mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_SCALE_DOWN) {
- mNextAppTransitionScaleUp =
- (mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_SCALE_UP);
- a = createThumbnailEnterExitAnimationLocked(getThumbnailTransitionState(enter),
- frame, transit, taskId);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) {
- String animName = mNextAppTransitionScaleUp ?
- "ANIM_THUMBNAIL_SCALE_UP" : "ANIM_THUMBNAIL_SCALE_DOWN";
- Slog.v(TAG, "applyAnimation:"
- + " anim=" + a + " nextAppTransition=" + animName
- + " transit=" + appTransitionToString(transit) + " isEntrance=" + enter
- + " Callers=" + Debug.getCallers(3));
- }
- } else if (mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_ASPECT_SCALE_UP ||
- mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_ASPECT_SCALE_DOWN) {
- mNextAppTransitionScaleUp =
- (mNextAppTransitionType == NEXT_TRANSIT_TYPE_THUMBNAIL_ASPECT_SCALE_UP);
- a = createAspectScaledThumbnailEnterExitAnimationLocked(
- getThumbnailTransitionState(enter), uiMode, orientation, transit, frame,
- insets, surfaceInsets, freeform, taskId);
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) {
- String animName = mNextAppTransitionScaleUp ?
- "ANIM_THUMBNAIL_ASPECT_SCALE_UP" : "ANIM_THUMBNAIL_ASPECT_SCALE_DOWN";
- Slog.v(TAG, "applyAnimation:"
- + " anim=" + a + " nextAppTransition=" + animName
- + " transit=" + appTransitionToString(transit) + " isEntrance=" + enter
- + " Callers=" + Debug.getCallers(3));
- }
- } else {
- int animAttr = 0;
- switch (transit) {
- case TRANSIT_ACTIVITY_OPEN:
- animAttr = enter
- ? WindowAnimation_activityOpenEnterAnimation
- : WindowAnimation_activityOpenExitAnimation;
- break;
- case TRANSIT_ACTIVITY_CLOSE:
- animAttr = enter
- ? WindowAnimation_activityCloseEnterAnimation
- : WindowAnimation_activityCloseExitAnimation;
- break;
- case TRANSIT_DOCK_TASK_FROM_RECENTS:
- case TRANSIT_TASK_OPEN:
- animAttr = enter
- ? WindowAnimation_taskOpenEnterAnimation
- : WindowAnimation_taskOpenExitAnimation;
- break;
- case TRANSIT_TASK_CLOSE:
- animAttr = enter
- ? WindowAnimation_taskCloseEnterAnimation
- : WindowAnimation_taskCloseExitAnimation;
- break;
- case TRANSIT_TASK_TO_FRONT:
- animAttr = enter
- ? WindowAnimation_taskToFrontEnterAnimation
- : WindowAnimation_taskToFrontExitAnimation;
- break;
- case TRANSIT_TASK_TO_BACK:
- animAttr = enter
- ? WindowAnimation_taskToBackEnterAnimation
- : WindowAnimation_taskToBackExitAnimation;
- break;
- case TRANSIT_WALLPAPER_OPEN:
- animAttr = enter
- ? WindowAnimation_wallpaperOpenEnterAnimation
- : WindowAnimation_wallpaperOpenExitAnimation;
- break;
- case TRANSIT_WALLPAPER_CLOSE:
- animAttr = enter
- ? WindowAnimation_wallpaperCloseEnterAnimation
- : WindowAnimation_wallpaperCloseExitAnimation;
- break;
- case TRANSIT_WALLPAPER_INTRA_OPEN:
- animAttr = enter
- ? WindowAnimation_wallpaperIntraOpenEnterAnimation
- : WindowAnimation_wallpaperIntraOpenExitAnimation;
- break;
- case TRANSIT_WALLPAPER_INTRA_CLOSE:
- animAttr = enter
- ? WindowAnimation_wallpaperIntraCloseEnterAnimation
- : WindowAnimation_wallpaperIntraCloseExitAnimation;
- break;
- case TRANSIT_TASK_OPEN_BEHIND:
- animAttr = enter
- ? WindowAnimation_launchTaskBehindSourceAnimation
- : WindowAnimation_launchTaskBehindTargetAnimation;
- }
- a = animAttr != 0 ? loadAnimationAttr(lp, animAttr) : null;
- if (DEBUG_APP_TRANSITIONS || DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation:"
- + " anim=" + a
- + " animAttr=0x" + Integer.toHexString(animAttr)
- + " transit=" + appTransitionToString(transit) + " isEntrance=" + enter
- + " Callers=" + Debug.getCallers(3));
- }
- return a;
- }
关于loadAnimation这个方法代码也是很多,但是逻辑非常简单了,就是根据设置的操作类型, 根据参数,使用loadAnimationRes()或loadAnimationAttr()或其他创建Animation接口来加载一个Animation出来。加载动画的时候需要注意一个优先级的问题。
比如Activity关闭的时候,加载的动画资源是下面这样
- <set xmlns:android="http://schemas.android.com/apk/res/android" android:zAdjustment="normal">
- <alpha android:fromAlpha="0.7" android:toAlpha="1.0"
- android:fillEnabled="true" android:fillBefore="true" android:fillAfter="true"
- android:interpolator="@interpolator/linear_out_slow_in"
- android:duration="250"/>
- </set>
动画设置好了之后,就会通过setAnimation方法将动画anim保存在AppWindowAnimator的成员变量animation中,动画的执行时候,就会来取这个animation。
- frameworks/base/services/core/java/com/android/server/wm/AppWindowAnimator.java
- public void setAnimation(Animation anim, int width, int height, boolean skipFirstFrame,
- int stackClip) {
- animation = anim;
- animating = false;
- if (!anim.isInitialized()) {
- anim.initialize(width, height, width, height);
- }
- ....
- }
刚刚在说动画的优先级的时候,说过如果设置了某种mNextAppTransitionType类型,就跟以这个mNextAppTransitionType类型作为返回,优先级高于第一种。这个过程的时序图如下。
- frameworks / base / services / core / java / com / android / server / wm / AppTransition.java
- void overridePendingAppTransition(String packageName, int enterAnim, int exitAnim, IRemoteCallback startedCallback) {
- if (isTransitionSet()) {
- clear();
- mNextAppTransitionType = NEXT_TRANSIT_TYPE_CUSTOM;
- mNextAppTransitionPackage = packageName;
- mNextAppTransitionEnter = enterAnim;
- mNextAppTransitionExit = exitAnim;
- postAnimationCallback();
- mNextAppTransitionCallback = startedCallback;
- } else {
- postAnimationCallback();
- }
- }
mNextAppTransitionType被覆盖了之后,创建动画的时候就会优先返回设置了这种类型的动画。
#####3、窗口动画设置
相对与过度动画,窗口动画的设置过程会简单一些,从commitFinishDrawingLocked方法说起,commitFinishDrawingLocked是也是从performSurfacePlacementInner里面调用而来的。
- boolean commitFinishDrawingLocked() {
- .....
- mDrawState = READY_TO_SHOW;
- boolean result = false;
- final AppWindowToken atoken = mWin.mAppToken;
- //去取出atoken,如果atoken等于null,那么说明不是Activity窗口,就可以调用performShowLocked,进行窗口动画的设置
- if (atoken == null || atoken.allDrawn || mWin.mAttrs.type == TYPE_APPLICATION_STARTING) {
- result = performShowLocked();
- }
- return result;
- }
performShowLocked中主要是调用了applyEnterAnimationLocked方法进行创建动画。
- void applyEnterAnimationLocked() {
- // If we are the new part of a window replacement transition and we have requested
- // not to animate, we instead want to make it seamless, so we don't want to apply
- // an enter transition.
- if (mWin.mSkipEnterAnimationForSeamlessReplacement) {
- return;
- }
- final int transit;
- if (mEnterAnimationPending) {
- mEnterAnimationPending = false;
- transit = WindowManagerPolicy.TRANSIT_ENTER;
- } else {
- transit = WindowManagerPolicy.TRANSIT_SHOW;
- }
- applyAnimationLocked(transit, true);.....
- }
mEnterAnimationPending的值等于true,说明当前所描述的窗口正在等待显示,也就是正处于不可见到可见状态的过程中,那WindowManagerService类的成员函数applyEnterAnimationLocked就会对该窗口设置一个类型为WindowManagerPolicy.TRANSIT_ENTER的动画,否则的话,就会对该窗口设置一个类型为WindowManagerPolicy.TRANSIT_SHOW的动画。后面会根据这个类型,确定styleable, 将参数transit的值转化为一个对应的动画样式名称。
- frameworks/base/services/core/java/com/android/server/wm/WindowStateAnimator.java
- boolean applyAnimationLocked(int transit, boolean isEntrance) {
- ......
- if (mService.okToDisplay()) {
- int anim = mPolicy.selectAnimationLw(mWin, transit);
- int attr = -1;
- Animation a = null;
- if (anim != 0) {
- a = anim != -1 ? AnimationUtils.loadAnimation(mContext, anim) : null;
- } else {
- switch (transit) {
- case WindowManagerPolicy.TRANSIT_ENTER:
- attr = com.android.internal.R.styleable.WindowAnimation_windowEnterAnimation;
- break;
- case WindowManagerPolicy.TRANSIT_EXIT:
- attr = com.android.internal.R.styleable.WindowAnimation_windowExitAnimation;
- break;
- case WindowManagerPolicy.TRANSIT_SHOW:
- attr = com.android.internal.R.styleable.WindowAnimation_windowShowAnimation;
- break;
- case WindowManagerPolicy.TRANSIT_HIDE:
- attr = com.android.internal.R.styleable.WindowAnimation_windowHideAnimation;
- break;
- }
- if (attr >= 0) {
- a = mService.mAppTransition.loadAnimationAttr(mWin.mAttrs, attr);
- }
- }
- if (DEBUG_ANIM) Slog.v(TAG,
- "applyAnimation: win=" + this
- + " anim=" + anim + " attr=0x" + Integer.toHexString(attr)
- + " a=" + a
- + " transit=" + transit
- + " isEntrance=" + isEntrance + " Callers " + Debug.getCallers(3));
- if (a != null) {
- if (DEBUG_ANIM) logWithStack(TAG, "Loaded animation " + a + " for " + this);
- setAnimation(a);
- mAnimationIsEntrance = isEntrance;
- }
- } else {
- clearAnimation();
- }
- Trace.traceEnd(Trace.TRACE_TAG_WINDOW_MANAGER);
- if (mWin.mAttrs.type == TYPE_INPUT_METHOD) {
- mService.adjustForImeIfNeeded(mWin.mDisplayContent);
- if (isEntrance) {
- mWin.setDisplayLayoutNeeded();
- mService.mWindowPlacerLocked.requestTraversal();
- }
- }
- return mAnimation != null;
- }
首先会调用PhoneWindowManager的selectAnimationLw方法去查找特殊窗口的动画类型,这里特殊窗口主要是StatusBar、NavigationBar或者窗口的类型是TYPE_DOCK_DIVIDER(分屏)等,如果是这些窗口的话,就会直接返回一个动画类型(transit)保存在anim中,接下来会判断anim是否为-1,因为selectAnimationLw在窗口是Keyguard或者DREAM类型的时候会返回-1,如果不是-1,说明查找到了,返回到WindowStateAnimator中使用AnimationUtils的loadAnimation方法去查找出一个动画a保存在Animation所描述的变量a中。
如果上面都不是,那么就根据transit类型,确定attr,调用AppTransition的loadAnimationAttr方法加载一个动画
- frameworks / base / services / core / java / com / android / server / wm / AppTransition.java Animation loadAnimationAttr(WindowManager.LayoutParams lp, int animAttr) {
- int anim = 0;
- Context context = mContext;
- if (animAttr >= 0) {
- AttributeCache.Entry ent = getCachedAnimations(lp);
- if (ent != null) {
- context = ent.context;
- anim = ent.array.getResourceId(animAttr, 0);
- }
- }
- if (anim != 0) {
- return AnimationUtils.loadAnimation(context, anim);
- }
- return null;
- }
- frameworks/base/services/core/java/com/android/server/wm/WindowStateAnimator.java
- public void setAnimation(Animation anim, long startTime, int stackClip) {
- if (localLOGV) Slog.v(TAG, "Setting animation in " + this + ": " + anim);
- mAnimating = false;
- mLocalAnimating = false;
- mAnimation = anim;
- ...
- }
最后动画被保存在WindowStateAnimator的成员变量mAnimation中。对比前面的过度动画,最后是
通过setAnimation方法将动画anim保存在AppWindowAnimator的成员变量animation中。当动画的执行时候,就会来取这个animation,动画的执行,放在接下来一节中更新。
来源: https://juejin.im/post/5a0581e451882534af256ca2