/* The following are each of the ActionBar.TabListener callbacks */
 @Override
 public void onTabSelected(CompatTab tab, FragmentTransaction ft) {
   // Check if the fragment is already initialized
   Fragment fragment = tab.getFragment();
   if (fragment == null) {
     // If not, instantiate and add it to the activity
     fragment = Fragment.instantiate(mActivity, mClass.getName());
     tab.setFragment(fragment);
     ft.add(android.R.id.tabcontent, fragment, tab.getTag());
   } else {
     // If it exists, simply attach it in order to show it
     ft.attach(fragment);
   }
 }
 @Override
 public void onTabUnselected(CompatTab tab, FragmentTransaction ft) {
   Fragment fragment = tab.getFragment();
   if (fragment != null) {
     // Detach the fragment, because another one is being attached
     ft.detach(fragment);
   }
 }