fetchGroupAnnouncement method

void fetchGroupAnnouncement ({String groupId, dynamic onSuccess(String announcement), dynamic onError(int errorCode, String desc) })

从服务器获取群公告

Implementation

void fetchGroupAnnouncement({
  final String groupId,
  onSuccess(String announcement),
  onError(int errorCode, String desc)}){
  Future<Map<String, dynamic>> result = _emGroupManagerChannel
      .invokeMethod(EMSDKMethod.fetchGroupAnnouncement, {"groupId" : groupId});
  result.then((response) {
    if (response['success']) {
      if (onSuccess != null) {
        if(response['value'] != null){
          onSuccess(response['value']);
        }else{
          onSuccess(null);
        }
      }
    } else {
      if (onError != null) onError(response['code'], response['desc']);
    }
  });
}