title: How image resources are recycled?
body: <p>Normally I always use <code>Drawable</code> resources in <code>Imageviews</code> because I haven't to manually release them.</p>
  
  <p>But in some cases I need to dynamically create bitmaps and then I've to manually call <code>recycle()</code> on them in <code>onDestroy()</code>. That's the best solution I've found according to <a href="https://stackoverflow.com/questions/7009086/recycle-imageviews-bitmap">that other StackOverflow question</a>.</p>
  
  <p>I want to understand how Android manages <code>Drawable</code> resources and why I haven't to manually recycle them. And when understood see if similar logic can be applied to manually created bitmaps. </p>