title: Send message from one activity to another
body: <p>I have an activity <code>(Activity_A)</code> that has a <code>handler</code> and is <code>receiving messages</code> from an external <code>library</code>. The problem is that <code>Activity_A</code> launches activity <code>Activity_B</code>. When <code>Activity_B</code> is launched, <code>Activity_A</code> <code>receives a message</code> on the <code>handler</code> that I want to "send" to <code>Activity_B</code>.</p>
  
  <p>How to do that?</p>
  
  <p>I cannot move the <code>handler</code> from <code>Activity_A</code> to <code>Activity_B</code> as some of the <code>messages</code> that receives have to be managed by <code>Activity_A.</code></p>
  
  <p>I would like to avoid using <code>global/static variables</code>.
  Is it possible to somehow save in <code>Activity_A</code> a reference to <code>Activity_B</code> when I create the <code>intent</code>? How to send a <code>message</code> from <code>Activity_A</code> to <code>Activity_B</code> ? </p>
  
  <p>An important point here is that, yes, I want to pass an object from one activity to another, but not in the moment I create the new activity (passing the object in a bundle). I want to do it asynchronously, whenever I receive a message from an external library. </p>