如何检测用户是否正在查看我的应用（Android）

Question

I am trying to check to see if the user is looking at my app when it receives a c2dm message. If the user is looking at it then there is no need to generate a notification, otherwise I will generate a notification. This seems to me like it would be quite trivial. However I have had a tough time trying to find a solution. Any help would be greatly appreciated.

Answer 1

If the user is looking at it then there is no need to generate a notification, otherwise I will generate a notification.

Have your C2DM receiver send an ordered broadcast. Have your activity (or activities) register a high-priority receiver for your broadcast, where they update themselves and abort the broadcast. Have a low-priority receiver for the broadcast registered in the manifest -- if it gets control, have it raise the Notification .

Answer 2

我唯一能想到的是在onResume（）中设置了一些标志，通知检查该标志...然后清除标志onDestroy或onPause

Answer 3

final ActivityManager activityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
if (yourActivity.getComponentName() == activityManager.getRunningTasks(1).get(0).topActivity) {
  // Activity is currently running

}

That's one way. Although I would probably use my activity's onStart() and onStop() to save a reference. There may be simpler ways too.