deleteMessage method
根据消息id messageId
删除消息
Implementation
Future<bool?> deleteMessage(String messageId) async {
Map req = this.toJson();
req['msg_id'] = messageId;
Map result = await _emConversationChannel.invokeMethod(
EMSDKMethod.removeMessage, req);
EMError.hasErrorFromResult(result);
return result.boolValue(EMSDKMethod.removeMessage);
}