title: Fragments overlapping when I am using fragmentTransaction.add method
body: <p>I am facing some weird issue with fragments, I am displaying google map on these two fragments, while switching from <code>Home Fragment</code> to <code>Request cab</code> fragment, in <code>Request cab</code> fragment, fragments are overlapping, I can see <code>Home Fragment</code> in background and its also clickable I can move map of <code>Home Fragment</code> too. This issue occur when I use <code>fragmentTransaction.add(R.id.frame, fragment, fragmenttag);</code>
   but if I use replace then its working fine, but I want to get the view back <code>onBackPressed</code> that is not possible with replacing the fragmnet. I am attaching screenshots and code. </p>
  
  <pre><code> public void changeFragment(final Fragment fragment, final String fragmenttag) {
      try {
          drawer_close();
          FragmentManager fragmentManager = getSupportFragmentManager();
          FragmentTransaction fragmentTransaction =
                  fragmentManager.beginTransaction().addToBackStack(null);
          fragmentTransaction.add(R.id.frame, fragment, fragmenttag);
          fragmentTransaction.commit();
      } catch (Exception e) {
      }
  }
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/Wuaki.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Wuaki.jpg" alt="Home Fragment"></a></p>
  
  <p><a href="https://i.stack.imgur.com/qzhrQ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qzhrQ.jpg" alt="Request Cab Fragment"></a></p>