OnAttach of a Dialog Listener for Version 23 and Below Version 23

I wrestled with this a little until I saw an implementation on the web and another on StackOverflow.  I'm posting it here so I can remember where to find it.  The version 23 Context method calls the Activity method, hence the check for Build.VERSION.SDK_INT < Build.VERSION_CODES.M, to avoid calling onAttachToContext twice, which results in a crash.

public interface NoticeDialogListener {
   public void onDialogPositiveClick( DialogFragment dialog );
   public void onDialogNegativeClick( DialogFragment dialog );
}

NoticeDialogListener _listener;

@TargetApi(23)
@Overridepublic void onAttach( Context context ) {
   super.onAttach(context);
   if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
      onAttachToContext(context);
   }
}

@SuppressWarnings("deprecation")
@Overridepublic void onAttach(Activity activity) {
   super.onAttach(activity);
   if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
      onAttachToContext(activity);
   }
}

public void onAttachToContext( Context context ) {
   Activity activity;

   if( context instanceof Activity ) {
      activity = (Activity) context;
      _listener = (NoticeDialogListener) activity;
   }
   else {
      _listener = (NoticeDialogListener) context;
   }
}