/**
  * Sets the root of the preference hierarchy that this activity is showing.
  *
  * @param preferenceScreen The root {@link PreferenceScreen} of the preference hierarchy.
  */
 public void setPreferenceScreen(PreferenceScreen preferenceScreen) {
   if (mPreferenceManager.setPreferences(preferenceScreen) && preferenceScreen != null) {
     postBindPreferences();
     CharSequence title = getPreferenceScreen().getTitle();
     // Set the title of the activity
     if (title != null) {
       setTitle(title);
     }
   }
 }
 @Override
 public void onContentChanged() {
   super.onContentChanged();
   postBindPreferences();
 }