title: Is there any way to have one and only one instance of each activity?
body: <p>I'm finding that in my application, the user can get quite 'nested' in the various activities that are opened while the user is using the application.</p>
  
  <p>For example:</p>
  
  <ol>
  <li>Main Menu</li>
  <li>Object List</li>
  <li>Object Details</li>
  <li>Object Edit</li>
  <li>Object Details</li>
  <li>Object Child Details</li>
  <li>Object Child Edit</li>
  <li>Object Child Details</li>
  </ol>
  
  <p>Now, when the user presses back, it has to go through 'Object Child Details' twice (same object, when it is edited it returns to the detailed page), and the same thing happens for the 'Parent Object Details'.</p>
  
  <p>Is there a way to reuse activities, if they are already open in the stack, and reorder them to the front? The only way I have seen is on activities with the <code>launcher</code> attribute. I believe I saw <code>singleTask</code> and <code>singleTop</code>.</p>
  
  <p>If am supposed to be using these two attributes, <code>singleTask</code> and <code>singleTop</code>, how am I supposed to use them? When I tried to include them in the application, it made no difference. Do I also need to set a flag while launching the intent using <code>startActivity</code>?</p>