title: blank screen appears before video is started playing android
body: <p>In my android app Ads are there which are like 20 sec after ads get finished the video which user wants to play is started but blank screen is appear for few minutes.</p>
  
  <p>After click on button in my activity the ads will be displayed as ads finished the video is displayed.My problem is that as soon as ads are finished then blank screen appear I think android is trying to buffer that video.
  I want to show some notification like progress bar/alert dialog telling the user that something is happening now since blank screen is appears user we feel nothing is happening. But I am not able to identify the point at which I should put notification. It depends on internet speed that video buffering.</p>