title: Android Button setPressed does not change animation
body: <p>I would like to abuse a standard button as a toggle button, but only when its longpressed. Therefore I first replaced the default style with background images for pressed, focused and default state.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
      &lt;selector xmlns:android="http://schemas.android.com/apk/res/android"&gt;
          &lt;item android:state_pressed="true" android:drawable="@drawable/btn_pressed" /&gt; &lt;!-- pressed --&gt;
          &lt;item android:state_focused="true" android:drawable="@drawable/btn_focused" /&gt; &lt;!-- focused --&gt;
          &lt;item android:drawable="@drawable/btn_default" /&gt; &lt;!-- default --&gt;
  
      &lt;/selector&gt;
  </code></pre>
  
  <p>I implemented both, onClickListener and OnLongClickListener following:</p>
  
  <pre><code>private OnLongClickListener mFireHoldListener = new OnLongClickListener() {
  
      @Override
      public boolean onLongClick(View view) {
          Log.i(TAG, "Long FIRE");
  
          Button btn = (Button) view;
          btn.setPressed(true);
          btn.invalidate();
          Log.i(TAG, "isPressed: " + btn.isPressed());
  
          return false;
      }
  
  };
  </code></pre>
  
  <p>If I perform a long click, the button doesn't change its background to the state_pressed. How can I keep the button pressed? Using a toggle button doesn't work as a normal click operation should be possible. If the button is pressed for a longer time, the button gets "locked".</p>
  
  <p>Many Thanks</p>