title: Can fragment be created with only one instance
body: <p>I was just wondering, can fragment creation only have one instance or singleton?<br>
  I went through <em>Google iosched</em> project too. They simply create</p>
  
  <pre><code>Fragment a = new Fragment();
  </code></pre>
  
  <p>Whenever they want...</p>
  
  <p>Suppose eg:</p>
  
  <pre><code>public static FragmentManager instance;
  
      public static FragmentManager getInstance() {
          if (instance == null) {
              instance = new FragmentManager();
          }
          return instance;
      }
  
      public TestFragment getTestFragment() {
          if (testFragment == null) {
              testFragment = new TestFragment ();
          }
  
          return  testFragment 
      }
  }
  </code></pre>
  
  <p>Can I use everywhere 
  <code>FragmentManager.getInstance().getTestFragment()</code> for transaction?</p>
  
  <p>eg:</p>
  
  <pre><code>getSupportFragmentManager()
      .beginTransaction()
      .replace(R.id.content_frame, FragmentManager.getInstance().getTestFragment())
      .commit();
  </code></pre>
  
  <p>Or OS automatically destroy the reference or some issues related to it?</p>