Launcher.java 文件源码

@Override
public void onDestroy() {
    super.onDestroy();

    // Remove all pending runnables
    mHandler.removeMessages(ADVANCE_MSG);
    mHandler.removeMessages(0);
    mWorkspace.removeCallbacks(mBuildLayersRunnable);

    // Stop callbacks from LauncherModel
    LauncherAppState app = (LauncherAppState.getInstance());

    // It's possible to receive onDestroy after a new Launcher activity has
    // been created. In this case, don't interfere with the new Launcher.
    if (mModel.isCurrentCallbacks(this)) {
        mModel.stopLoader();
        app.setLauncher(null);
    }

    try {
        mAppWidgetHost.stopListening();
    } catch (NullPointerException ex) {
        Log.w(TAG, "problem while stopping AppWidgetHost during Launcher destruction", ex);
    }
    mAppWidgetHost = null;

    mWidgetsToAdvance.clear();

    TextKeyListener.getInstance().release();

    unregisterReceiver(mCloseSystemDialogsReceiver);

    mDragLayer.clearAllResizeFrames();
    ((ViewGroup) mWorkspace.getParent()).removeAllViews();
    mWorkspace.removeAllWorkspaceScreens();
    mWorkspace = null;
    mDragController = null;

    LauncherAnimUtils.onDestroyActivity();

    if (mLauncherCallbacks != null) {
        mLauncherCallbacks.onDestroy();
    }
}