focus.md

IActivityManager setFocusedRootTask

试试switch user

moveActivityTaskToBack 是不是能将activity暂停

ActivityManager 这个也是调用的 IActivityManager @RequiresPermission(android.Manifest.permission.REORDER_TASKS) public void moveTaskToFront(int taskId, @MoveTaskFlags int flags, Bundle options) { try { ActivityThread thread = ActivityThread.currentActivityThread(); IApplicationThread appThread = thread.getApplicationThread(); String packageName = mContext.getOpPackageName(); getTaskService().moveTaskToFront(appThread, packageName, taskId, flags, options); } catch (RemoteException e) { throw e.rethrowFromSystemServer(); } }

试试 

WindowManagerGlobal.java 的 addview

IActivityTaskManager setFocusedTask

 @Override
public void setFocusedTask(int taskId) {
    enforceTaskPermission("setFocusedTask()");
    final long callingId = Binder.clearCallingIdentity();
    try {
        synchronized (mGlobalLock) {
            setFocusedTask(taskId, null /* touchedActivity */);
        }
    } finally {
        Binder.restoreCallingIdentity(callingId);
    }
}

@Override
public void focusTopTask(int displayId) {
    enforceTaskPermission("focusTopTask()");
    final long callingId = Binder.clearCallingIdentity();
    try {
        synchronized (mGlobalLock) {
            final DisplayContent dc = mRootWindowContainer.getDisplayContent(displayId);
            if (dc == null) return;
            final Task task = dc.getTask((t) -> t.isLeafTask() && t.isTopActivityFocusable(),
                    true /*  traverseTopToBottom */);
            if (task == null) return;
            setFocusedTask(task.mTaskId, null /* touchedActivity */);
        }
    } finally {
        Binder.restoreCallingIdentity(callingId);
    }
}