isLoginBefore method Null safety

Future<bool> isLoginBefore()

Implementation

Future<bool> isLoginBefore() async {
  Map result = await _channel.invokeMethod(ChatMethodKeys.isLoggedInBefore);
  try {
    EMError.hasErrorFromResult(result);
    return result.boolValue(ChatMethodKeys.isLoggedInBefore);
  } on EMError catch (e) {
    throw e;
  }
}