当从本机视图收到数据时，如何在flatter中更新小部件-Android

来自Android本机主机$count的Hello

我使用methodChannel在Flatter和Android原生视图之间进行通信 应用程序开始->Main.dart（1个按钮）->打开Android的MainActivity->打开NativeView活动，这里按钮计数器的onTap增量为1，日志以上面的消息打印，但我也想在颤振屏幕上显示此消息

我在做什么？？短暂性脑缺血发作

主飞镖

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() => runApp(new MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter-Native Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(title: 'Channel Demo App'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  final String title;

  MyHomePage({Key key, this.title}) : super(key: key) {}

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  static const platform = const MethodChannel('flutter.channel');
  var valueFromNative = 0;

  @override
  void initState() {
    super.initState();
    platform.setMethodCallHandler(_handleMethod);
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(
        child: new Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new RaisedButton(
              child: new Text('Show native view'),
              onPressed: _showNativeView,
            ),
            new RaisedButton(
                child: new Text(valueFromNative.toString()),
                onPressed: () {
                  print("CHECK THIS VAL $valueFromNative");
                }),
          ],
        ),
      ),
    );
  }

  Future<Null> _showNativeView() async {
    await platform.invokeMethod('showNativeView');
  }

  Future<void> _handleMethod(MethodCall call) async {
    switch (call.method) {
      case "message":
        print("CHECK THIS");
        //Able to get console log here
        debugPrint(call.arguments);
        setState(() {
          new Text(call.arguments);
          valueFromNative = call.arguments;
        });
         print("CHECK THIS VAL ${call.arguments}"); //but not able to get value here

        break;
    }
  }
}

NativeViewActivity.kt

package flutter.channel

import android.content.Intent
import android.os.Bundle
import android.util.Log
import io.flutter.app.FlutterActivity
import io.flutter.plugin.common.MethodChannel
import io.flutter.plugins.GeneratedPluginRegistrant

class MainActivity() : FlutterActivity() {
    companion object {
        const val CHANNEL = "flutter.channel"
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        GeneratedPluginRegistrant.registerWith(this)

        MethodChannel(flutterView, CHANNEL).setMethodCallHandler { call, result ->
            if (call.method == "showNativeView") {
                val intent = Intent(this, NativeViewActivity::class.java)
                startActivity(intent)
                result.success(true)
                
            } else {
                result.notImplemented()
            }
        }
    }
 
}

package flutter.channel

import android.os.Bundle
import android.util.Log
import android.widget.Button
import android.widget.TextView
import flutter.channel.MainActivity
import flutter.channel.R
import io.flutter.app.FlutterActivity
import io.flutter.plugin.common.EventChannel
import io.flutter.plugin.common.MethodChannel

class NativeViewActivity : FlutterActivity() {
    var count = 0

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        val channel = MethodChannel(flutterView, MainActivity.CHANNEL)

        setContentView(R.layout.layout)
        val tvCount = findViewById<TextView>(R.id.tvCount)
        findViewById<Button>(R.id.button).setOnClickListener {
            ++count
            tvCount.text = count.toString()
            channel.invokeMethod("message", "Hello from Android native host $count");
            
        }
    }
}

package flatter.channel
导入android.os.Bundle
导入android.util.Log
导入android.widget.Button
导入android.widget.TextView
导入flatter.channel.main活动
导入颤振.channel.R
导入io.flatter.app.flatterActivity
导入io.flatter.plugin.common.EventChannel
导入io.flatter.plugin.common.MethodChannel
类NativeViewActivity:Activity（）{
变量计数=0
重写创建时的乐趣（savedInstanceState:Bundle？）{
super.onCreate（savedInstanceState）
val通道=方法通道（视图，MainActivity.channel）
setContentView（R.layout.layout）
val tvCount=findViewById（R.id.tvCount）
findViewById（R.id.button）.setOnClickListener{
++计数
tvCount.text=count.toString（）
invokeMethod（“消息”，“来自Android本机主机$count的你好”）；
}
}
}