title: When should one use android:clickable?
body: <p>When should we use <code>android:clickable</code> in XML? Should we ever?<br>
  Is there any difference between such XML declaration and in-code declaration <code>myButton.setOnClickListener</code>? I have read the documentation, but I could not find out when and why should I ever use this attribute. </p>
  
  <p>PS. I was implementing an ad SDK and found that their developers were using <code>android:clickable</code> with <code>WebView</code> and I was intrigued why did they use it.</p>