打開WMS的staring window日志
設置WindowManagerDebugConfig的
static final boolean DEBUG_STARTING_WINDOW = true;

從log和代碼分析
1.setAppStartingWindow
首先針對主題進行檢查 有一些主題下是不能顯示startingwindow的

final boolean windowIsTranslucent = ent.array.getBoolean(com.android.internal.R.styleable.Window_windowIsTranslucent, false);final boolean windowIsFloating = ent.array.getBoolean(com.android.internal.R.styleable.Window_windowIsFloating, false);final boolean windowDisableStarting = ent.array.getBoolean(com.android.internal.R.styleable.Window_windowDisablePreview, false);

如上面三種
另外對于設置了
final boolean windowShowWallpaper = ent.array.getBoolean(
com.android.internal.R.styleable.Window_windowShowWallpaper, false); 以背景為壁紙
還要設置
windowFlags |= FLAG_SHOW_WALLPAPER

檢查完主題之后 根據主題設置依稀樣式相關的數據 保存在StartingData 數據結構里面,然后拋出消息給mH所在線程處理

wtoken.startingData = new StartingData(pkg, theme, compatInfo, nonLocalizedLabel,labelRes, icon, logo, windowFlags);Message m = mH.obtainMessage(H.ADD_STARTING, wtoken);// Note: we really want to do sendMessageAtFrontOfQueue() because we// want to process the message ASAP, before any other queued// messages.if (DEBUG_STARTING_WINDOW) Slog.v(TAG_WM, "Enqueueing ADD_STARTING");mH.sendMessageAtFrontOfQueue(m);

設置AppWindowToken.startingView 為創建的decorview

2.處理過程case ADD_STARTING
通過日志可以分析 首先創建window和viww 通過PhoneWindowManager創建window 和viewRoot,并且addWindow到WMS,
創建WindowState和surface數據 整個過程可以根據log看出

mPolicy.addStartingWindow(wtoken.token, sd.pkg, sd.theme,sd.compatInfo, sd.nonLocalizedLabel, sd.labelRes, sd.icon, sd.logo,sd.windowFlags, overrideConfig); 12-29 08:30:31.314 31101-32230/system_process V/WindowManager: setAppStartingWindow: token=Token{5108b27 ActivityRecord{cea59e6 u0 com.android.providers.downloads.ui/.activity.InterDownloadTaskDetailActivity t4}} pkg=com.android.providers.downloads.ui transferFrom=null 12-29 08:30:31.314 31101-32230/system_process V/WindowManager: Checking theme of starting window: 0x100d0017 12-29 08:30:31.314 31101-32230/system_process V/WindowManager: Translucent=false Floating=false ShowWallpaper=false 12-29 08:30:31.314 31101-32230/system_process V/WindowManager: Creating StartingData 12-29 08:30:31.314 31101-32230/system_process V/WindowManager: Enqueueing ADD_STARTING

之后的階段就是有過幾次事務狀態變化,但是mDrawState=DRAW_PENDING 不做任何處理,直到客戶端最后調用mWindowSession.finishDrawing(mWindow) 周后才會對動畫狀態進行切換,切換到COMMIT_DRAW_PENDING

12-29 08:30:31.344 31101-32230/system_process I/WindowManager: commitFinishDrawingLocked: Window{4730896 u0 Starting com.android.providers.downloads.ui} cur mDrawState=DRAW_PENDING 12-29 08:30:31.344 31101-32230/system_process D/WindowManager: updateWindows: starting Window{4730896 u0 Starting com.android.providers.downloads.ui} isOnScreen=false allDrawn=false freezingScreen=false 12-29 08:30:31.358 31101-32230/system_process I/WindowManager: commitFinishDrawingLocked: Window{4730896 u0 Starting com.android.providers.downloads.ui} cur mDrawState=DRAW_PENDING 12-29 08:30:31.358 31101-32230/system_process D/WindowManager: updateWindows: starting Window{4730896 u0 Starting com.android.providers.downloads.ui} isOnScreen=false allDrawn=false freezingScreen=false 12-29 08:30:31.360 31101-31218/system_process V/WindowManager: Finishing drawing window Window{4730896 u0 Starting com.android.providers.downloads.ui}: mDrawState=DRAW_PENDING

4 這是在進行事務處理的時候就會有所變化,切換到READY_TO_SHOW狀態,但是由于現在app還沒有準備好 mAppTransition.isReady() ==false 還不能繪制

12-29 08:30:31.360 31101-31218/system_process V/WindowManager: Draw state now committed in Window{4730896 u0 Starting com.android.providers.downloads.ui} 12-29 08:30:31.361 31101-31218/system_process I/WindowManager: commitFinishDrawingLocked: Window{4730896 u0 Starting com.android.providers.downloads.ui} cur mDrawState=COMMIT_DRAW_PENDING12-29 08:30:31.362 31101-31218/system_process V/WindowManager: performShow on WindowStateAnimator{7e561ed Starting com.android.providers.downloads.ui}: mDrawState=READY_TO_SHOW readyForDisplay=false starting=true during animation: policyVis=true attHidden=false tok.hiddenRequested=true tok.hidden=true animating=false tok animating=false Callers=com.android.server.wm.WindowStateAnimator.commitFinishDrawingLocked:631 com.android.server.wm.WindowSurfacePlacer.applySurfaceChangesTransaction:761 com.android.server.wm.WindowSurfacePlacer.performSurfacePlacementInner:324 12-29 08:30:31.362 31101-31218/system_process D/WindowManager: updateWindows: starting Window{4730896 u0 Starting com.android.providers.downloads.ui} isOnScreen=false allDrawn=false freezingScreen=false 12-29 08:30:31.365 31101-32230/system_process I/WindowManager: commitFinishDrawingLocked: Window{4730896 u0 Starting com.android.providers.downloads.ui} cur mDrawState=READY_TO_SHOW

5 直到handleAppTransitionReadyLocked被調用之后 app才準備好 readyForDisplay,就可以把狀態切換為HAS_DRAWN
mDrawState = HAS_DRAWN

12-29 08:30:31.373 31101-32230/system_process V/WindowManager: performShow on WindowStateAnimator{7e561ed Starting com.android.providers.downloads.ui}: mDrawState=READY_TO_SHOW readyForDisplay=true starting=true during animation: policyVis=true attHidden=false tok.hiddenRequested=false tok.hidden=false animating=false tok animating=false Callers=com.android.server.wm.AppWindowAnimator.showAllWindowsLocked:458 com.android.server.wm.WindowSurfacePlacer.handleOpeningApps:1263 com.android.server.wm.WindowSurfacePlacer.handleAppTransitionReadyLocked:1197

6 真正的window啟動之后,就會改變windowState的mAttrs.type 變成非TYPE_APPLICATION_STARTING的,
執行void onFirstWindowDrawn(WindowState win, WindowStateAnimator winAnimator)方法
該方法會把 方法哦WMS的mFinishString隊列中 之后發送消息

void onFirstWindowDrawn(WindowState win, WindowStateAnimator winAnimator) {firstWindowDrawn = true;// We now have a good window to show, remove dead placeholdersremoveAllDeadWindows();if (startingData != null) {if (DEBUG_STARTING_WINDOW || DEBUG_ANIM) Slog.v(TAG, "Finish starting "+ win.mToken + ": first real window is shown, no animation");// If this initial window is animating, stop it -- we will do an animation to reveal// it from behind the starting window, so there is no need for it to also be doing its// own stuff.winAnimator.clearAnimation();winAnimator.mService.mFinishedStarting.add(this);winAnimator.mService.mH.sendEmptyMessage(H.FINISHED_STARTING);}updateReportedVisibilityLocked();} 12-29 08:30:31.486 31101-31218/system_process V/WindowManager: Finish starting AppWindowToken{8089f7d token=Token{5108b27 ActivityRecord{cea59e6 u0 com.android.providers.downloads.ui/.activity.InterDownloadTaskDetailActivity t4}}}: first real window is shown, no animation

7 之后WMS處理消息 case FINISHED_STARTING:
調用mPolicy.removeStartingWindow(token, view) 移除window

8 最后destorySurface的時候清理

總結

以上是生活随笔為你收集整理的App StartingWindow分析的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。