flutter开发实战-inappwebview实现flutter与Javascript的交互JSBridge

import 'package:flutter/material.dart';
import 'package:flutter_inappwebview/flutter_inappwebview.dart';
 
class MyInAppWebViewPage extends StatefulWidget {
  @override
  _MyInAppWebViewPageState createState() => new _MyInAppWebViewPageState();
}
 
class _MyInAppWebViewPageState extends State<MyInAppWebViewPage> {
 
  InAppWebViewController webView;
  String jsBridgeScript = """
    window.flutter_inappwebview_jsbridge = {
      callMethod: function(method, successCallback, errorCallback, args) {
        flutter_inappwebview.callMethod(method, successCallback, errorCallback, args);
      },
      subscribeToMethod: function(method, callback) {
        flutter_inappwebview.subscribeToMethod(method, callback);
      },
      subscribeToEvent: function(eventName, callback) {
        flutter_inappwebview.subscribeToEvent(eventName, callback);
      },
      unsubscribeFromMethod: function(subscriptionId) {
        flutter_inappwebview.unsubscribeFromMethod(subscriptionId);
      },
      unsubscribeFromEvent: function(subscriptionId) {
        flutter_inappwebview.unsubscribeFromEvent(subscriptionId);
      }
    };
  """;
 
  @override
  void initState() {
    super.initState();
  }
 
  @override
  void dispose() {
    super.dispose();
  }
 
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
            title: Text("InAppWebView")
        ),
        body: Container(
            child: Column(children: <Widget>[
              Expanded(
                child: InAppWebView(
                  initialUrlRequest: URLRequest(url: Uri.parse("https://www.example.com")),
                  initialJavaScript: jsBridgeScript,
                  onWebViewCreated: (InAppWebViewController controller) {
                    webView = controller;
                  },
                  onLoadStart: (InAppWebViewController controller, String url) {
                  },
                  onLoadStop: (InAppWebViewController controller, String url) {
                  },
                ),
              )
            ])
        )
    );
  }
}

这个代码实例展示了如何在Flutter应用中使用InAppWebView插件创建一个包含JSBridge的WebView，从而实现Flutter与JavaScript的交互。通过定义jsBridgeScript变量，我们创建了一个简单的JSBridge，允许Flutter调用JavaScript函数并接收来自Web内容的事件和方法回调。