how to make button clickable or touchable only on image visible area?
<p>I am using custom RadioButton, where i need to make clickable only on the image visible area.
As you can see in the image below , where I need to make clickable only on the image portion ie White and Green portion only, the black area will remain transparent and non clickable.</p>

<p><img src="http://i.stack.imgur.com/hEj2g.png" alt="enter image description here"></p>

<p>Thanks ,
Any help will really be appreciated.</p>
