Android6.0 亮屏灭屏流程(DisplayPowerController、WMS)(一)WMS绘制.doc

Android6.0 亮屏灭屏流程（DisplayPowerController、WMS）（一）WMS绘制亮屏、灭屏流程整个流程涉及的模块比较多，包括PowerManagerService、DisplayPowerControl、WMS、AMS。因此在分析完WMS之后，我们把这块也分析下。DisplayPowerControl我们知道灭屏流程的发起是在PowerManagerService中，会通过updatePowerState函数调用updateDisplayPowerStateLocked函数，再调用DisplayPowerControl的requestPowerState函数，到DisplayPowerControl中。DisplayPowerControl中后面会调用updatePowerState函数，我们也主要从这个函数开始分析：updatePowerState会根据PowerManagerService传过来的显示状态，然后调用animateScreenStateChange函数。cpp view plain copyanimateScreenStateChange(state, performScreenOffTransition); 下面我们先来看animateScreenStateChange函数：cpp view plain copyprivate void animateScreenStateChange(int target, boolean performScreenOffTransition) / If there is already an animation in progress, dont interfere with it. if (mColorFadeOnAnimator.isStarted() | mColorFadeOffAnimator.isStarted() return; / If we were in the process of turning off the screen but didnt quite / finish. Then finish up now to prevent a jarring transition back / to screen on if we skipped blocking screen on as usual. if (mPendingScreenOff & target != Display.STATE_OFF) setScreenState(Display.STATE_OFF); mPendingScreenOff = false; mPowerState.dismissColorFadeResources(); if (target = Display.STATE_ON) /亮屏处理 / Want screen on. The contents of the screen may not yet / be visible if the color fade has not been dismissed because / its last frame of animation is solid black. if (!setScreenState(Display.STATE_ON) return; / screen on blocked if (USE_COLOR_FADE_ON_ANIMATION & mPowerRequest.isBrightOrDim() /亮屏动画 / Perform screen on animation. if (mPowerState.getColorFadeLevel() = 1.0f) mPowerState.dismissColorFade(); else if (mPowerState.prepareColorFade(mContext, mColorFadeFadesConfig ? ColorFade.MODE_FADE : ColorFade.MODE_WARM_UP) mColorFadeOnAnimator.start(); else mColorFadeOnAnimator.end(); else /跳过亮屏动画 / Skip screen on animation. mPowerState.setColorFadeLevel(1.0f); mPowerState.dismissColorFade(); else if (target = Display.STATE_DOZE) / Want screen dozing. / Wait for brightness animation to complete beforehand when entering doze / from screen on to prevent a perceptible jump because brightness may operate / differently when the display is configured for dozing. . else if (target = Display.STATE_DOZE_SUSPEND) / Want screen dozing and suspended. / Wait for brightness animation to complete beforehand unless already / suspended because we may not be able to change it after suspension. . else /灭屏处理 / Want screen off. mPendingScreenOff = true; if (mPowerState.getColorFadeLevel() = 0.0f) /灭屏动画结束 / Turn the screen off. / A black surface is already hiding the contents of the screen. setScreenState(Display.STATE_OFF); mPendingScreenOff = false; mPowerState.dismissColorFadeResources(); else if (performScreenOffTransition & mPowerState.prepareColorFade(mContext, mColorFadeFadesConfig ? ColorFade.MODE_FADE : ColorFade.MODE_COOL_DOWN) & mPowerState.getScreenState() != Display.STATE_OFF) / Perform the screen off animation. mColorFadeOffAnimator.start();/开启灭屏动画 else / Skip the screen off animation and add a black surface to hide the / contents of the screen. mColorFadeOffAnimator.end();/关闭灭屏动画 animateScreenStateChange在亮屏的处理的时候，先会调用setScreenState(Display.STATE_ON），然后根据USE_COLOR_FADE_ON_ANIMATION 判断是否要开启亮屏动画，这里我们是没有设置的。因此直接跳过亮屏动画。灭屏的处理的话，会有一个灭屏动画（也是注册一个VSync信号回调函数处理的，这里我们不分析了），当动画结束后，直接就调用setScreenState(Display.STATE_OFF)结束。我们再来看看setScreenState函数cpp view plain copyprivate boolean setScreenState(int state) if (mPowerState.getScreenState() != state) final boolean wasOn = (mPowerState.getScreenState() != Display.STATE_OFF); mPowerState.setScreenState(state); . / Tell the window manager policy when the screen is turned off or on unless its due / to the proximity sensor. We temporarily block turning the screen on until the / window manager is ready by leaving a black surface covering the screen. / This surface is essentially the final state of the color fade animation and / it is only removed once the window manager tells us that the activity has / finished drawing underneath. final boolean isOff = (state = Display.STATE_OFF); if (isOff & mReportedScreenStateToPolicy != REPORTED_TO_POLICY_SCREEN_OFF & !mScreenOffBecauseOfProximity) mReportedScreenStateToPolicy = REPORTED_TO_POLICY_SCREEN_OFF; unblockScreenOn(); mWindowManagerPolicy.screenTurnedOff();/调用PhoneWindowManager的screenTurnedOff else if (!isOff & mReportedScreenStateToPolicy = REPORTED_TO_POLICY_SCREEN_OFF) mReportedScreenStateToPolicy = REPORTED_TO_POLICY_SCREEN_TURNING_ON; if (mPowerState.getColorFadeLevel() = 0.0f) blockScreenOn(); else unblockScreenOn(); mWindowManagerPolicy.screenTurningOn(mPendingScreenOnUnblocker);/调用PhoneWindowManager的screenTurningOn函数 / Return true if the screen isnt blocked. return mPendingScreenOnUnblocker = null; setScreenState函数，先是调用了DisplayPowerState的setScreenState函数，然后根据屏幕是灭屏还是亮屏调用PhoneWindowManager的相关函数。PhoneWindowManager的screenTurnedOff和screenTurningOn函数PhoneWindowManager的screenTurnedOff函数主要是通知kerguard，屏幕灭屏了。cpp view plain copyOverride public void screenTurnedOff() if (DEBUG_WAKEUP) Slog.i(TAG, Screen turned off.); updateScreenOffSleepToken(true); synchronized (mLock) mScreenOnEarly = false; mScreenOnFully = false; mKeyguardDrawComplete = false; mWindowManagerDrawComplete = false; mScreenOnListener = null; updateOrientationListenerLp(); if (mKeyguardDelegate != null) mKeyguardDelegate.onScreenTurnedOff(); 我们再来看PhoneWindowManager的screenTurningOn函数。当有keyguard时，我们会先发一个延时的MSG_KEYGUARD_DRAWN_TIMEOUT信号，并且会调用keyguard的onScreenTurningOn函数，当完成会调用mKeyguardDrawnCallback回调函数。我们这里还要注意下有一个屏幕点亮后的回调。cpp view plain copy 在CODE上查看代码片派生到我的代码片Override public void screenTurningOn(final ScreenOnListener screenOnListener) if (DEBUG_WAKEUP) Slog.i(TAG, Screen turning on.); updateScreenOffSleepToken(false); synchronized (mLock) mScreenOnEarly = true; mScreenOnFully = false; mKeyguardDrawComplete = false; mWindowManagerDrawComplete = false; mScreenOnListener = screenOnListener;/屏幕点亮后的回调 if (mKeyguardDelegate != null) if (DEBUG_WAKEUP) Slog.d(TAG, send delay message MSG_KEYGUARD_DRAWN_TIMEOUT); mHandler.removeMessages(MSG_KEYGUARD_DRAWN_TIMEOUT); mHandler.sendEmptyMessageDelayed(MSG_KEYGUARD_DRAWN_TIMEOUT, 1000); mKeyguardDelegate.onScreenTurningOn(mKeyguardDrawnCallback); else if (DEBUG_WAKEUP) Slog.d(TAG, null mKeyguardDelegate: setting mKeyguardDrawComplete.); finishKeyguardDrawn(); 我们先看下mKeyguardDrawnCallback 回调，就是发送MSG_KEYGUARD_DRAWN_COMPLETE（keyguard绘制完的消息）cpp view plain copy 在CODE上查看代码片派生到我的代码片final DrawnListener mKeyguardDrawnCallback = new DrawnListener() Override public void onDrawn() if (DEBUG_WAKEUP) Slog.d(TAG, mKeyguardDelegate.ShowListener.onDrawn.); mHandler.sendEmptyMessage(MSG_KEYGUARD_DRAWN_COMPLETE); ; 我们再来看看MSG_KEYGUARD_DRAWN_COMPLETE以及MSG_KEYGUARD_DRAWN_TIMEOUT信号的处理，都会调用finishKeyguardDrawn函数。cpp view plain copy 在CODE上查看代码片派生到我的代码片case MSG_KEYGUARD_DRAWN_COMPLETE: if (DEBUG_WAKEUP) Slog.w(TAG, Setting mKeyguardDrawComplete); finishKeyguardDrawn(); break; case MSG_KEYGUARD_DRAWN_TIMEOUT: Slog.w(TAG, Keyguard drawn timeout. Setting mKeyguardDrawComplete); finishKeyguardDrawn(); break; 我们再来看看finishKeyguardDrawn函数，会先去除队列中的MSG_KEYGUARD_DRAWN_TIMEOUT消息（因为之前发的MSG_KEYGUARD_DRAWN_TIMEOUT消息，可能keyguard结束发送MSG_KEYGUARD_DRAWN_COMPLETE消息调用的finishKeyguardDrawn就要把MSG_KEYGUARD_DRAWN_TIMEOUT去除了）。然后会调用cpp view plain copy 在CODE上查看代码片派生到我的代码片private void finishKeyguardDrawn() synchronized (mLock) if (!mScreenOnEarly | mKeyguardDrawComplete) return; / We are not awake yet or we have already informed of this event. mKeyguardDrawComplete = true; if (mKeyguardDelegate != null) mHandler.removeMessages(MSG_KEYGUARD_DRAWN_TIMEOUT); mWindowManagerDrawComplete = false; / . eventually calls finishWindowsDrawn which will finalize our screen turn on / as well as enabling the orientation change logic/sensor. mWindowManagerInternal.waitForAllWindowsDrawn(mWindowManagerDrawCallback, WAITING_FOR_DRAWN_TIMEOUT); 最后我们再看看WMS的waitForAllWindowsDrawn函数，以及两个参数mWindowManagerDrawCallback和一个WAITING_FOR_DRAWN_TIMEOUT（1秒）。WMS的waitForAllWindowsDrawn函数我们先来看看WMS的waitForAllWindowsDrawn函数，会把传进来的回调保存在mWaitingForDrawnCallback 。然后遍历所有的windows，把需要显示或者已经显示的窗口全部加入到mWaitingForDrawn，然后调用requestTraversalLocked这个函数我们之前分析过，就是发送一个消息，重新刷新UI布局。然后我们继续分析这个函数，如果mWaitingForDrawn为空，代表没啥显示的直接调用回调函数，如果mWaitingForDrawn有要显示的窗口，就要会先发送一个WAITING_FOR_DRAWN_TIMEOUT，这个timeout之前传进来的是1秒。然后调用checkDrawnWindowsLocked函数。cpp view plain copy 在CODE上查看代码片派生到我的代码片Override public void waitForAllWindowsDrawn(Runnable callback, long timeout) synchronized (mWindowMap) mWaitingForDrawnCallback = callback;/回调保存在mWaitingForDrawnCallback final WindowList windows = getDefaultWindowListLocked(); for (int winNdx = windows.size() - 1; winNdx = 0; -winNdx) final WindowState win = windows.get(winNdx); final boolean isForceHiding = mPolicy.isForceHiding(win.mAttrs); Slog.i(TAG,In the function waitForAllWindowsDrawn); if (win.isVisibleLw() & (win.mAppToken != null | isForceHiding) Slog.i(TAG,In the function win.isVisibleLw(); win.mWinAnimator.mDrawState = WindowStateAnimator.DRAW_PENDING; / Force add to mResizingWindows. win.mLastContentInsets.set(-1, -1, -1, -1); mWaitingForDrawn.add(win); / No need to wait for the windows below Keyguard. if (isForceHiding) break; requestTraversalLocked(); mH.removeMessages(H.WAITING_FOR_DRAWN_TIMEOUT); if (mWaitingForDrawn.isEmpty() callback.run(); Slog.i(TAG,In the function mWaitingForDrawn.isEmpty(); else mH.sendEmptyMessageDelayed(H.WAITING_FOR_DRAWN_TIMEOUT, timeout); checkDrawnWindowsLocked(); Slog.i(TAG,In the function checkDrawnWindowsLocked(); 我们先来看下checkDrawnWindowsLocked函数，这个函数。遍历之前加入的mWaitingForDrawn（要显示的窗口），这个时候我们把已经去除的，不需要显示的，没有surface的窗口从mWaitingForDrawn去除，还有已经绘制好的也去除。然后再当mWaitingForDrawn为空时，就发送ALL_WINDOWS_DRAWN消息。cpp view plain copy 在CODE上查看代码片派生到我的代码片void checkDrawnWindowsLocked() if (mWaitingForDrawn.isEmpty() | mWaitingForDrawnCallback = null) return; for (int j = mWaitingForDrawn.size() - 1; j = 0; j-) WindowState win = mWaitingForDrawn.get(j); if (win.mRemoved | !win.mHasSurface | !win.mPolicyVisibility) / Window has been removed or hidden; no draw will now happen, so stop waiting. if (DEBUG_SCREEN_ON) Slog.w(TAG, Aborted waiting for drawn: + win); mWaitingForDrawn.remove(win); else if (win.hasDrawnLw() / Window is w drawn (and shown). if (DEBUG_SCREEN_ON) Slog.d(TAG, Window drawn win= + win); mWaitingForDrawn.remove(win); if (mWaitingForDrawn.isEmpty() if (DEBUG_SCREEN_ON) Slog.d(TAG, All windows drawn!); mH.removeMessages(H.WAITING_FOR_DRAWN_TIMEOUT); mH.sendEmptyMessage(H.ALL_WINDOWS_DRAWN); ALL_WINDOWS_DRAWN消息的处理就是清除mWaitingForDrawnCallback ，然后调用回调。cpp view plain copy 在CODE上查看代码片派生到我的代码片case ALL_WINDOWS_DRAWN: Runnable callback; synchronized (mWindowMap) callback = mWaitingForDrawnCallback; mWaitingForDrawnCallback = null; if (callback != null) callback.run(); 还有当我们调用waitForAllWindowsDrawn一般都是有需要显示的窗口，但是我们直接调用checkDrawnWindowsLocked函数，发现有的窗口还没绘制完成。那么我们就要等，会在刷新的核心函数中performLayoutAndPlaceSurfacesLockedInner有如下代码，这个时候如果之前还没绘制完成的窗口，绘制好了。会再调用checkDrawnWindowsLocked函数，如果mWaitingForDrawn中的窗口绘制好了，会在mWaitingForDrawn中去除这个窗口。然后mWaitingForDrawn为空了，之后会发送ALL_WINDOWS_DRAWN消息，还调用mWaitingForDrawnCallback回调函数。cpp view plain copy 在CODE上查看代码片派生到我的代码片if (mWaitingForDrawnCallback != null | (mInnerFields.mOrientationChangeComplete & !defaultDisplay.layoutNeeded & !mInnerFields.mUpdateRotation) checkDrawnWindowsLocked(); 当然如果我们之前没有把mWaitingForDrawn中的窗口清空，最后在WAITING_FOR_DRAWN_TIMEOUT（这里是1秒）时间到了也会调用回调的。cpp view plain copy 在CODE上查看代码片派生到我的代码片case WAITING_FOR_DRAWN_TIMEOUT: Runnable callback = null; synchronized (mWindowMap) Slog.w(TAG, Timeout waiting for drawn: undrawn= + mWaitingForDrawn); mWaitingForDrawn.clear(); callback = mWaitingForDrawnCallback; mWaitingForDrawnCallback = null; if (callback != null) callback.run(); break; PhoneWindowManager窗口绘制完成的回调函数那下面我们就要继续看PhoneWindowManager中窗口绘制完成之后的回调函数。代码如下就是发送了一个消息。cpp view plain copy 在CODE上查看代码片派生到我的代码片final Runnable mWindowManagerDrawCallback = new Runnable() Override public void run() if (DEBUG_WAKEUP) Slog.i(TAG, All windows ready for display!); mHandler.sendEmptyMessage(MSG_WINDOW_MANAGER_DRAWN_COMPLETE); ; 我们来看这个消息的处理cpp view plain copy 在CODE上查看代码片派生到我的代码片case MSG_WINDOW_MANAGER_DRAWN_COMPLETE: if (DEBUG_WAKEUP) Slog.w(TAG, Setting mWindowManagerDrawComplete); finishWindowsDrawn(); break; finishWindowsDrawn就是把mWindowManagerDrawComplete 置为true，然后调用finishScreenTurningOn函数。cpp view plain copy 在CODE上查看代码片派生到我的代码片private void finishWindowsDrawn() synchronized (mLock) if (!mScreenOnEarly | mWindowManagerDrawComplete) return; / Screen is not turned on or we did already handle this case earlier. mWindowManagerDrawComplete = true; finishScreenTurningOn(); finishScreenTurningOn函数调用了之前在DisplayPowerControl中调用screenTurningOn传入的回调，然后再调用WMS的enableScreenIfNeeded函数。cpp view plain copy 在CODE上查看代码片派生到我的代码片private void finishScreenTurningOn() ed (mLock) updateOrientationListenerLp(); final ScreenOnListener listener; final boolean enableScreen; synchronized (mLock) if (mScreenOnFully | !mScreenOnEarly | !mWindowManagerDrawComplete | (mAwake & !mKeyguardDrawComplete) return; / spurious or not ready yet listener = mScreenOnListener; mScreenOnListener = null; mScreenOnFully = true; . if (listener != null) listener.onScreenOn(); if (enableScreen) try mWindowManager.enableScreenIfNeeded(); catch (RemoteException unhandled) 我们先分析下WMS的enableScreenIfNeeded函数，然后再看DisplayPowerControl的回调onScreenOn函数。WMS的enableScreenIfNeeded函数WMS的enableScreenIfNeeded函数就是调用了enableScreenIfNeededLocked函数cpp view plain copy 在CODE上查看代码片派生到我的代码片Override public void enableScreenIfNeeded() synchronized (mWindowMap) enableScreenIfNeededLocked(); enableScreenIfNeededLocked这个函数仅仅是保证mDisplayEnabled为true，如果为true直接结束。cpp view plain copy 在CODE上查看代码片派生到我的代码片void enableScreenIfNeededLocked() if (mDisplayEnabled) return; if (!mSystemBooted & !mShowingBootMessages) return; mH.sendEmptyMessage