title: Android ImageView - setAlpha(float) vs setImageAlpha(int)
body: <p>Using <a href="https://stackoverflow.com/a/31551723/2810825">this</a> answer as a reference, I understand that a <code>View's</code> <code>setAlpha(float)</code> basically draws the view normally on a buffer, then uses a 2nd pass to draw the view with the alpha value on the scene, and because of this, setting a <code>View's</code> alpha usually involves harming the performance of the app.</p>
  
  <p>However, <code>ImageViews</code> have another method called <code>setImageAlpha(int)</code> which, from what I've gathered, applies the alpha value on the <code>ImageView's</code> colour filter - removing the need for a 2nd pass all together and is therefore much more efficient.</p>
  
  <p>My question is - since using <code>setImageAlpha</code> on an <code>ImageView</code> is much more efficient, is there any reason to ever use <code>setAlpha(float)</code> on an <code>ImageView</code>? Or should this be avoided in general in favour for <code>setImageAlpha(int)?</code></p>