title: Start Activity with action, but no category
body: <p>I am trying to start an activity defined in another apk, in its AndroidManifest.xml, it defines an activity and with an action, but no category defined.</p>
  
  <p>The format is like</p>
  
  <pre><code>&lt;activity name="..."&gt;
      &lt;intent-filter&gt;
          &lt;action android:name="action name"&gt;
      &lt;intent-filter&gt;
  &lt;/activity&gt;
  </code></pre>
  
  <p>My code is following</p>
  
  <pre><code>Intent i = new Intent("action name");
  startActivity(i);
  </code></pre>
  
  <p>However my apk crashed with uncaught ActivityNotFound exception, the logs read
  No Activity found to handle intent ... "</p>
  
  <p>Any thoughts?</p>
  
  <p>Thanx a lot.</p>