startCallback method Null safety
Start contact and group, chatroom callback.
Reference:
Call this method when you ui is ready, then will receive ChatRoomManagerListener, ChatContactManagerListener, ChatGroupManagerListener callback.
Implementation
Future<void> startCallback() async {
Map result = await _channel.invokeMethod(ChatMethodKeys.startCallback);
try {
ChatError.hasErrorFromResult(result);
} on ChatError catch (e) {
throw e;
}
}