title: How can I force iOS to change background color immediately?
body: <p>Is there any way to change the background color of a window immediately?</p>
  
  <p>I need a blinking background, i.e. red/green blinking in an interval of a second. As i see, the background color will not change immediately, but only when function is left.</p>
  
  <p>Is there any way to force the system to change it and redraw the window's background immediately?</p>