public static FriendActivity instance = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  instance = this;
  initViews();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
  if (requestCode == REQUEST_CODE_NEW_CONTACT && resultCode == RESULT_OK) {
    FriendActivity.instance.reFreshFriendList();
  }
}

// 广播通知
Intent intent = new Intent();
intent.setAction("action.refreshFriend");
sendBroadcast(intent);

@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_main);
   IntentFilter intentFilter = new IntentFilter();
   intentFilter.addAction("action.refreshFriend");
   registerReceiver(mRefreshBroadcastReceiver, intentFilter);
   initViews();
}
// broadcast receiver
private BroadcastReceiver mRefreshBroadcastReceiver = new BroadcastReceiver() {
   @Override
   public void onReceive(Context context, Intent intent) {
     String action = intent.getAction();
     if (action.equals("action.refreshFriend"))
     {
       reFreshFrinedList();
     }
   }
};

@Override
protected void onDestroy() {
    super.onDestroy();
    unregisterReceiver(mRefreshBroadcastReceiver);
}