launch method
Implementation
Future<SNSMobileSDKResult> launch() async {
_channel.setMethodCallHandler(_onMethodCallHandler);
final Map<dynamic, dynamic> map = await _channel.invokeMethod('onLaunchSDK', _toArguments()); // as FutureOr<Map<dynamic, dynamic>>);
return Future.value(SNSMobileSDKResult.fromMap(map));
}