title: Make the "up" button behave like the "back" button on Android
body: <p>The Android app design I'm working with calls for the "Up" button to behave the same way the "Back" button behaves, but I'm not sure how to make that happen.</p>
  
  <p>I know that <code>android:parentActivityName</code> must be specified for the "Up" button to be visible on an activity, but specifying a fixed parent activity doesn't really make sense for the activity.  Imagine this scenario with activities A, B, and C:</p>
  
  <ol>
  <li>Launch into activity A, it contains two buttons: each taking you to activities B and C, respectively.</li>
  <li>Tap the button for activity B.</li>
  <li>Transition to activity B. it contains two buttons: each taking you to activities A and C, respectively.</li>
  <li>Tap the button for activity C.</li>
  <li>Transition to activity C.</li>
  <li>Tap the "up" button, you <strong>should</strong> be taken to activity B.</li>
  <li>On activity B now: tap the button for activity A.</li>
  <li>Transition to activity A.</li>
  <li>Tap the "up" button, you <strong>should</strong> be taken to activity B.</li>
  <li>On activity B Tap the "up" button, you <strong>should</strong> be taken to activity A.</li>
  <li>On activity A now: tap the button for activity C.</li>
  <li>Transition to activity C.</li>
  <li>Tap the "up" button, you <strong>should</strong> be taken to activity A.</li>
  </ol>
  
  <p>If I were to specify <code>android:parentActivityName</code> for each activity, it might make sense to have B and C's parent activity be A, but this means that each time we hit the "up" button from activities B or C, we land at activity A (and that's not always what is supposed to happen).</p>
  
  <p>Does anybody have experience with this type of thing?</p>