title: How to correctly set icon size of a button in extjs?
body: <p>I'm using extjs4 and What i'm trying to do seems to be simple but i can't find a working solution for it.</p>
  
  <p>I have a 64*64px icon and i want my button to show it as the background image but extjs only shows the image <strong><em>partially</em></strong>.Googled on the net for a solution but nobody suggested a <strong><em>working</em></strong> solution for it.I just want my background image fit to my button.</p>
  
  <p>here is my js code:</p>
  
  <pre class="lang-js prettyprint-override"><code>{
      xtype : 'button',
      text : null,
      iconCls : 'startbutton',
      //icon:'./assets/icons/startbtn.png',
      //style:{height:'60px'},
      width : 64,
      height : 64
  }
  </code></pre>
  
  <p>here is my css code:</p>
  
  <pre class="lang-css prettyprint-override"><code>.x-btn-icon .startbutton {
      background-image: url(start.png) !important;
  }
  </code></pre>
  
  <p>i tried some css combinations and still no success.</p>