title: How to invalidate() a View from another thread?
body: <p>I've got a couple of Views that are updated once a second by a Timer task. They can't <code>invalidate()</code> themselves because "only the original thread that created a view hierarchy can touch its views".</p>
  
  <p>There is a function called <a href="http://developer.android.com/reference/android/app/Activity.html#runOnUiThread%28java.lang.Runnable%29" rel="nofollow"><code>runOnUiThread</code></a> for this, but I need an Activity to run it.</p>
  
  <p>How can I solve this problem?</p>
  
  <p>Edit: Is this what <code>postInvalidate()</code> is for? How guaranteed am I that the invalidation and update will happen soon (if the UI thread isn't busy)?</p>