title: how to remove background resource of Button?
body: <p><a href="https://stackoverflow.com/questions/9269896/how-to-remove-button-background-resource">How to remove button background resource</a> i refered this, But my need is to remove button background and that should change background as per deviceDefault theme.  Means just removing the resource added last time, not assigning new Resource.</p>
  
  <p>Can anybody help to solve this prob ? Thank You</p>