这是一个简单的实现，展示了：

1. 将字符串值从Flutter传递到Android代码
2. 从Android代码获得响应以应对混乱

代码基于以下示例：https：//flutter.io/platform-
channels/#codec

1.传递字符串值“ text”：

String text = "whatever";

Future<Null> _getBatteryLevel(text) async {
String batteryLevel;
try {
  final String result = await platform.invokeMethod('getBatteryLevel',{"text":text}); 
  batteryLevel = 'Battery level at $result % .';
} on PlatformException catch (e) {
  batteryLevel = "Failed to get battery level: '${e.message}'.";
}

setState(() {
  _batteryLevel = batteryLevel;
});

}

2.在RandomFunction（）之后获取响应“电池电量”；

 public void onMethodCall(MethodCall call, MethodChannel.Result result) {
                    if (call.method.equals("getBatteryLevel")) {

                        text = call.argument("text");
                        String batteryLevel = RandomFunction(text);

                        if (batteryLevel != null) {
                            result.success(batteryLevel);
                        } else {
                            result.error("UNAVAILABLE", "Battery level not available.", null);
                        }
                    } else {
                        result.notImplemented();
                    }
                }

希望这可以帮助！