[移动开发]Android R: mFocusedWindow和mFocusedApp更新流程

Android R: mFocusedWindow和mFocusedApp更新流程

有些场景下会根据mFocusedWindow和mFocusedApp做一下开发。
所以，分析mFocusedWindow和mFocusedApp更新流程还是有必要的。

1，mFocusedWindow更新流程

mFocusedWindow是WindowState类
mFocusedWindow在DisplayPolicy类中
mFocusedWindow更新的接口在：
WindowManagerService.updateFocusedWindowLocked()

其他类也会调用updateFocusedWindowLocked方法。
例如: WindowToken, ActivityRecord, WindowState
例如ActivityRecord 在 commitVisibility() 通过：
    mWmService.updateFocusedWindowLocked(UPDATE_FOCUS_WILL_PLACE_SURFACES,false)
来更新mFocusedWindow

WindowManagerService.java
boolean updateFocusedWindowLocked(int mode, boolean updateInputWindows)
->
RootWindowContainer.java
updateFocusedWindowLocked()
->
DisplayContent.java
updateFocusedWindowLocked() {
  getDisplayPolicy().focusChangedLw()
}
->
DisplayPolicy.java
public int focusChangedLw(WindowState lastFocus, WindowState newFocus) {
    mFocusedWindow = newFocus;
}

2, mFocusedApp更新流程

mFocusedApp是ActivityRecord类
mFocusedApp在DisplayContent类中
mFocusedApp的更新接口在：
ActivityTaskManagerService.setResumedActivityUncheckLocked()

其他类，如ActivityRecord也会调用setFocusedApp()
ActivityTaskManagerService.java
setResumedActivityUncheckLocked() {
  r.getDisplay().setFocusedApp(r, true);
}
->
DisplayContent.java
void setFocusedApp(ActivityRecord r, boolean moveFocusNow)
->
boolean setFocusedApp(ActivityRecord newFocus) {
  mFocusedApp = newFocus;
  ..
  // 更新焦点应用到InputDispatcher.cpp中
  getInputMonitor().setFocusedAppLw(newFocus);
}

InputMonitor.java
public void setFocusedAppLw(ActivityRecord newApp) {
    // Focused app has changed.
    if (newApp == null) {
        mService.mInputManager.setFocusedApplication(mDisplayId, null);
    } else {
        final InputApplicationHandle handle = newApp.mInputApplicationHandle;
        handle.name = newApp.toString();
        handle.dispatchingTimeoutNanos = newApp.mInputDispatchingTimeoutNanos;

        mService.mInputManager.setFocusedApplication(mDisplayId, handle);
    }
}

3，调试

dumpsys input | grep -i focus
dumpsys window | grep -i focus