Android : How to show dialog or activity over lock screen[ not unlock the screen]

Question

I hava a app, it will receive msg from server and make a dialog to user.So when phone is on lock screen i want dialog will show on the top of lock screen but not unlock it.c

Answer 1

public void onAttachedToWindow() {
      Window window = getWindow();
      window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
           | WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
           | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
           | WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
}