Android P WMS(4) -- removewindow
Android P WMS(5) -- relayoutWindow
Android P WMS(6) -- windowanimator
Android P WMS(7) --wms 問題種類和debug技巧
Android P WMS(8) --View SYstem 簡介
1.APP啓動addWindow過程
我們在WMS addWindow添加打印堆棧log
//在WMS添加如下堆棧
@WindowManagerService.java
public int addWindow(Session session, IWindow client, int seq,
LayoutParams attrs, int viewVisibility, int displayId, Rect outFrame,
Rect outContentInsets, Rect outStableInsets, Rect outOutsets,
DisplayCutout.ParcelableWrapper outDisplayCutout, InputChannel outInputChannel) {
new Exception("William WindowManagerService stack").printStackTrace(); //add log
然後在launcher點擊啓動settings,log如下。第一次在啓動splash screen時執行addWindow，來至於SplashScreenStartingData.createStartingSurface,第二次是啓動settings主界面 com.android.settings/com.android.settings.Settings。這一部分可以參考：
Android解析WindowManager（三）Window的添加過程
//發現啓動settings時，會先啓動Splash Screen(啓動畫面也叫歡迎頁)
1077 1148 W System.err: java.lang.Exception: William WindowManagerService stack
1077 1148 W System.err: at com.android.server.wm.WindowManagerService.addWindow(WindowManagerService.java:1157)
1077 1148 W System.err: at com.android.server.wm.Session.addToDisplay(Session.java:205)
1077 1148 W System.err: at android.view.ViewRootImpl.setView(ViewRootImpl.java:771)
1077 1148 W System.err: at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:356)
1077 1148 W System.err: at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:93)
1077 1148 W System.err: at com.android.server.policy.PhoneWindowManager.addSplashScreen(PhoneWindowManager.java:3214)
1077 1148 W System.err: at com.android.server.wm.SplashScreenStartingData.createStartingSurface(SplashScreenStartingData.java:56)
1077 1148 W System.err: at com.android.server.wm.AppWindowContainerController$1.run(AppWindowContainerController.java:170)
1077 1148 W System.err: at android.os.Handler.handleCallback(Handler.java:873)
1077 1148 W System.err: at android.os.Handler.dispatchMessage(Handler.java:99)
1077 1148 W System.err: at android.os.Looper.loop(Looper.java:193)
1077 1148 W System.err: at android.os.HandlerThread.run(HandlerThread.java:65)
1077 1148 W System.err: at com.android.server.ServiceThread.run(ServiceThread.java:44)
1077 1148 V WindowManager: Window Window{e56651a u0 Splash Screen com.android.settings} client=android.view.ViewRootImpl$W@f2667c5 token=AppWindowToken{4be29e3 token=Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}} (Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}) params={(0,0)(fillxfill) ty=APPLICATION_STARTING wanim=0x10302f8
1077 1148 V WindowManager: Attaching Window{e56651a u0 Splash Screen com.android.settings} token=AppWindowToken{4be29e3 token=Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}}
1077 1148 V WindowManager: addWindow: New client android.view.ViewRootImpl$W@f2667c5: window=Window{e56651a u0 Splash Screen com.android.settings} Callers=com.android.server.wm.Session.addToDisplay:205 android.view.ViewRootImpl.setView:771 android.view.WindowManagerGlobal.addView:356 android.view.WindowManagerImpl.addView:93 com.android.server.policy.PhoneWindowManager.addSplashScreen:3214
//然後才add settings window(com.android.settings/com.android.settings.Settings)
1077 1236 W System.err: java.lang.Exception: William WindowManagerService stack
1077 1236 W System.err: at com.android.server.wm.WindowManagerService.addWindow(WindowManagerService.java:1157)
1077 1236 W System.err: at com.android.server.wm.Session.addToDisplay(Session.java:205)
1077 1236 W System.err: at android.view.IWindowSession$Stub.onTransact(IWindowSession.java:129)
1077 1236 W System.err: at com.android.server.wm.Session.onTransact(Session.java:164)
1077 1236 V WindowManager: Window Window{c70e488 u0 com.android.settings/com.android.settings.Settings} client=android.os.BinderProxy@d12a82b token=AppWindowToken{4be29e3 token=Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}} (Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}) params={(0,0)(fillxfill) sim={forwardNavigation} ty=BASE_APPLICATION wanim=0x10302f8
1077 1236 V WindowManager: Attaching Window{c70e488 u0 com.android.settings/com.android.settings.Settings} token=AppWindowToken{4be29e3 token=Token{afc8e12 ActivityRecord{f88399d u0 com.android.settings/.Settings t7}}}
1077 1236 V WindowManager: First window added to Session{d84ba9c 3168:1000}, creating SurfaceSession
1077 1236 V WindowManager: addWindow: New client android.os.BinderProxy@d12a82b: window=Window{c70e488 u0 com.android.settings/com.android.settings.Settings} Callers=com.android.server.wm.Session.addToDisplay:205 android.view.IWindowSession$Stub.onTransact:129 com.android.server.wm.Session.onTransact:164 android.os.Binder.execTransact:731 <bottom of call stack>
Android解析WindowManager（三）Window的添加過程
1.0 概述
WindowManager對Window進行管理，說到管理那就離不開對Window的添加、更新和刪除的操作，在這裏我們把它們統稱爲Window的操作。對於Window的操作，最終都是交由WMS來進行處理。窗口的操作分爲兩大部分，一部分是WindowManager處理部分，另一部分是WMS處理部分。我們知道Window分爲三大類，分別是：Application Window（應用程序窗口）、Sub Windwow（子窗口）和System Window（系統窗口），對於不同類型的窗口添加過程會有所不同，但是對於WMS處理部分，添加的過程基本上是一樣的， WMS對於這三大類的窗口基本是“一視同仁”的。
1.1 Activity的添加過程
@frameworks/base/core/java/android/app/ActivityThread.java
final void handleResumeActivity(IBinder token,
boolean clearHide, boolean isForward, boolean reallyResume, int seq, String reason) {
...
r = performResumeActivity(token, clearHide, reason);//1
...
if (r.window == null && !a.mFinished && willBeVisible) {
r.window = r.activity.getWindow();
View decor = r.window.getDecorView();
decor.setVisibility(View.INVISIBLE);
ViewManager wm = a.getWindowManager();//2
WindowManager.LayoutParams l = r.window.getAttributes();
a.mDecor = decor;
l.type = WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
l.softInputMode |= forwardBit;
if (r.mPreserveWindow) {
a.mWindowAdded = true;
r.mPreserveWindow = false;
ViewRootImpl impl = decor.getViewRootImpl();
if (impl != null) {
impl.notifyChildRebuilt();
}
}
if (a.mVisibleFromClient && !a.mWindowAdded) {
a.mWindowAdded = true;
wm.addView(decor, l);//3
}
}
註釋1處的performResumeActivity方法最終會調用Activity的onResume方法。在註釋2處得到ViewManager類型的wm對象，
在註釋3處調用了wm的addView方法，而addView方法的實現則是在WindowManagerImpl中，此後的過程在上面的系統窗口的添加過程已經講過，
唯一需要注意的是addView的第一個參數是DecorView。
1.2 系統窗口的添加過程
三大類窗口的添加過程會有所不同，這裏以系統窗口StatusBar爲例，StatusBar是SystemUI的重要組成部分，具體就是指系統狀態欄，用於顯示時間、電量和信號等信息。我們來查看StatusBar的實現類PhoneStatusBar的addStatusBarWindow方法，這個方法負責爲StatusBar添加Window，如下所示。
@/frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBar.java
private void addStatusBarWindow() {
makeStatusBarView();
mStatusBarWindowManager = Dependency.get(StatusBarWindowManager.class);
mRemoteInputController = new RemoteInputController(mHeadsUpManager);
mStatusBarWindowManager.add(mStatusBarWindow, getStatusBarHeight());
}
@/frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarWindowManager.java
public void add(View statusBarView, int barHeight) {
// Now that the status bar window encompasses the sliding panel and its
// translucent backdrop, the entire thing is made TRANSLUCENT and is
// hardware-accelerated.
mLp = new WindowManager.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
barHeight,
WindowManager.LayoutParams.TYPE_STATUS_BAR,
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
| WindowManager.LayoutParams.FLAG_TOUCHABLE_WHEN_WAKING
| WindowManager.LayoutParams.FLAG_SPLIT_TOUCH
| WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
| WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS,
PixelFormat.TRANSLUCENT);
mLp.token = new Binder();
mLp.flags |= WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED;
mLp.gravity = Gravity.TOP;
mLp.softInputMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE;
mLp.setTitle("StatusBar");
mLp.packageName = mContext.getPackageName();
mStatusBarView = statusBarView;
mBarHeight = barHeight;
mWindowManager.addView(mStatusBarView, mLp); //mWindowManager
mLpChanged = new WindowManager.LayoutParams();
mLpChanged.copyFrom(mLp);
}
//WindowManager繼承ViewManager，因此還是在ViewManager
@frameworks/base/core/java/android/view/WindowManager.java
/**
* The interface that apps use to talk to the window manager.
* </p><p>
@SystemService(Context.WINDOW_SERVICE)
public interface WindowManager extends ViewManager {
//包括addview update remove
@/frameworks/base/core/java/android/view/ViewManager.java
public interface ViewManager
public void addView(View view, ViewGroup.LayoutParams params);
public void updateViewLayout(View view, ViewGroup.LayoutParams params);
public void removeView(View view);
}
//WindowManagerImpl具體實現addView
public final class WindowManagerImpl implements WindowManager {
private final WindowManagerGlobal mGlobal = WindowManagerGlobal.getInstance();
@Override
public void addView(@NonNull View view, @NonNull ViewGroup.LayoutParams params) {
applyDefaultToken(params);
mGlobal.addView(view, params, mContext.getDisplay(), mParentWindow);
}
@frameworks/base/core/java/android/view/WindowManagerGlobal.java
public void addView(View view, ViewGroup.LayoutParams params,
Display display, Window parentWindow) {
...//參數檢查
final WindowManager.LayoutParams wparams = (WindowManager.LayoutParams) params;
if (parentWindow != null) {
parentWindow.adjustLayoutParamsForSubWindow(wparams);//1
} else {
...
}
ViewRootImpl root;
View panelParentView = null;
...
root = new ViewRootImpl(view.getContext(), display);//2
view.setLayoutParams(wparams);
mViews.add(view);
mRoots.add(root);//3
mParams.add(wparams);
}
try {
root.setView(view, wparams, panelParentView);//4
} catch (RuntimeException e) {
...
}
}
/**
* We have one child
*/
public void setView(View view, WindowManager.LayoutParams attrs, View panelParentView) {
synchronized (this) {
try {
mOrigWindowType = mWindowAttributes.type;
mAttachInfo.mRecomputeGlobalAttributes = true;
collectViewAttributes();
res = mWindowSession.addToDisplay(mWindow, mSeq, mWindowAttributes,
getHostVisibility(), mDisplay.getDisplayId(),
mAttachInfo.mContentInsets, mAttachInfo.mStableInsets,
mAttachInfo.mOutsets, mInputChannel);
}
}
@/frameworks/base/services/core/java/com/android/server/wm/Session.java
public int addToDisplay(IWindow window, int seq, WindowManager.LayoutParams attrs,
int viewVisibility, int displayId, Rect outContentInsets, Rect outStableInsets,
Rect outOutsets, InputChannel outInputChannel) {
return mService.addWindow(this, window, seq, attrs, viewVisibility, displayId, //就調用到了wms::addWindow
outContentInsets, outStableInsets, outOutsets, outInputChannel);
}
2.Window的添加過程（WMS部分）
frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
public int addWindow(Session session, IWindow client, int seq,
WindowManager.LayoutParams attrs, int viewVisibility, int displayId,
Rect outContentInsets, Rect outStableInsets, Rect outOutsets,
InputChannel outInputChannel) {
int[] appOp = new int[1];
int res = mPolicy.checkAddPermission(attrs, appOp);//1
if (res != WindowManagerGlobal.ADD_OKAY) {
return res;
}
...
synchronized(mWindowMap) {
if (!mDisplayReady) {
throw new IllegalStateException("Display has not been initialialized");
}
final DisplayContent displayContent = mRoot.getDisplayContentOrCreate(displayId);//2
if (displayContent == null) {
Slog.w(TAG_WM, "Attempted to add window to a display that does not exist: "
+ displayId + ". Aborting.");
return WindowManagerGlobal.ADD_INVALID_DISPLAY;
}
...
if (type >= FIRST_SUB_WINDOW && type <= LAST_SUB_WINDOW) {//3
parentWindow = windowForClientLocked(null, attrs.token, false);//4
if (parentWindow == null) {
Slog.w(TAG_WM, "Attempted to add window with token that is not a window: "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_SUBWINDOW_TOKEN;
}
if (parentWindow.mAttrs.type >= FIRST_SUB_WINDOW
&& parentWindow.mAttrs.type <= LAST_SUB_WINDOW) {
Slog.w(TAG_WM, "Attempted to add window with token that is a sub-window: "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_SUBWINDOW_TOKEN;
}
}
...
}
...
}
WMS的addWindow返回的是addWindow的各種狀態，比如添加Window成功，無效的display等等，這些狀態被定義在WindowManagerGlobal中。
註釋1處根據Window的屬性，調用WMP的checkAddPermission方法來檢查權限，具體的實現在PhoneWindowManager的checkAddPermission方法中，如果沒有權限則不會執行後續的代碼邏輯。註釋2處通過displayId來獲得窗口要添加到哪個DisplayContent上，如果沒有找到DisplayContent，則返回WindowManagerGlobal.ADD_INVALID_DISPLAY這一狀態，其中DisplayContent用來描述一塊屏幕。註釋3處，type代表一個窗口的類型，它的數值介於FIRST_SUB_WINDOW和LAST_SUB_WINDOW之間（1000~1999），這個數值定義在WindowManager中，說明這個窗口是一個子窗口，不瞭解窗口類型取值範圍的請閱讀Android解析WindowManager（二）Window的屬性這篇文章。註釋4處，attrs.token是IBinder類型的對象，windowForClientLocked方法內部會根據attrs.token作爲key值從mWindowMap中得到該子窗口的父窗口。接着對父窗口進行判斷，如果父窗口爲null或者type的取值範圍不正確則會返回錯誤的狀態。
...
AppWindowToken atoken = null;
final boolean hasParent = parentWindow != null;
WindowToken token = displayContent.getWindowToken(
hasParent ? parentWindow.mAttrs.token : attrs.token);//1
final int rootType = hasParent ? parentWindow.mAttrs.type : type;//2
boolean addToastWindowRequiresToken = false;
if (token == null) {
if (rootType >= FIRST_APPLICATION_WINDOW && rootType <= LAST_APPLICATION_WINDOW) {
Slog.w(TAG_WM, "Attempted to add application window with unknown token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
if (rootType == TYPE_INPUT_METHOD) {
Slog.w(TAG_WM, "Attempted to add input method window with unknown token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
if (rootType == TYPE_VOICE_INTERACTION) {
Slog.w(TAG_WM, "Attempted to add voice interaction window with unknown token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
if (rootType == TYPE_WALLPAPER) {
Slog.w(TAG_WM, "Attempted to add wallpaper window with unknown token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
...
if (type == TYPE_TOAST) {
// Apps targeting SDK above N MR1 cannot arbitrary add toast windows.
if (doesAddToastWindowRequireToken(attrs.packageName, callingUid,
parentWindow)) {
Slog.w(TAG_WM, "Attempted to add a toast window with unknown token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
}
final IBinder binder = attrs.token != null ? attrs.token : client.asBinder();
token = new WindowToken(this, binder, type, false, displayContent,
session.mCanAddInternalSystemWindow);//3
} else if (rootType >= FIRST_APPLICATION_WINDOW && rootType <= LAST_APPLICATION_WINDOW) {//4
atoken = token.asAppWindowToken();//5
if (atoken == null) {
Slog.w(TAG_WM, "Attempted to add window with non-application token "
+ token + ". Aborting.");
return WindowManagerGlobal.ADD_NOT_APP_TOKEN;
} else if (atoken.removed) {
Slog.w(TAG_WM, "Attempted to add window with exiting application token "
+ token + ". Aborting.");
return WindowManagerGlobal.ADD_APP_EXITING;
}
} else if (rootType == TYPE_INPUT_METHOD) {
if (token.windowType != TYPE_INPUT_METHOD) {
Slog.w(TAG_WM, "Attempted to add input method window with bad token "
+ attrs.token + ". Aborting.");
return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
}
}
...
addWindow方法總結
addWindow方法分了3個部分來進行講解，主要就是做了下面4件事：
1. 對所要添加的窗口進行檢查，如果窗口不滿足一些條件，就不會再執行下面的代碼邏輯。
2. WindowToken相關的處理，比如有的窗口類型需要提供WindowToken，沒有提供的話就不會執行下面的代碼邏輯，有的窗口類型則需要由WMS隱式創建WindowToken。
3. WindowState的創建和相關處理，將WindowToken和WindowState相關聯。
4. 創建和配置DisplayContent，完成窗口添加到系統前的準備工作。
參考鏈接：
Android解析WindowManagerService（二）WMS的重要成員和Window的添加過程
http://androidxref.com/8.0.0_r4/
《深入理解Android：卷III》