Youtube player on my Android App

Hi how can I implement a youtube player for my App using a webview? I've done this before but when I press the back button the youtube player/webview should also close. Here's my current code:

var movieUrl = "http://www.youtube.com/embed/" + trailerId + "?fs=1&autoplay=1";
webview = Ti.UI.createWebView({
  url : movieUrl,
  width: Titanium.UI.FILL,
  enableZoomControls: false,
  scalesPageToFit: true,
  scrollsToTop: false,
});
 
win.add(webview);