title: Fitting a ImageView half the screen height and full the screen width
body: <p>How it is : <a href="http://i49.tinypic.com/352lxdt.png" rel="nofollow">http://i49.tinypic.com/352lxdt.png</a>
  How I want : <a href="http://i45.tinypic.com/bahc1.png" rel="nofollow">http://i45.tinypic.com/bahc1.png</a></p>
  
  <p>how to do this via XML and also via code.?
  I am using RelativeLayout.
  also want API level 8 (from android 2.3+)..
  so cant use setWidth(), setHeight()
  help..?</p>