颤振 ||编辑或删除 WebView 的弹出窗口

Question

在我的 flutter WebView 项目中，有一种方法可以编辑或删除从网站到我们的 WebView 的弹出窗口。

例如，在我们的 Flutter 应用程序 WebView 中将“离开网站”更改为“离开应用程序”。非常感谢任何帮助。

Answer 1

 var noncase = "self.onbeforeunload=null";
                webViewController?.runJavascript( noncase);

您可以使用 javascript 禁用 webview 中的离开弹出窗口

小部件

Scaffold(
        floatingActionButton: Row(
          mainAxisAlignment: MainAxisAlignment.end,
          children: [
            FloatingActionButton(
              onPressed: () {
                webViewController?.goBack();
              },
              child: Icon(Icons.arrow_back),
            ),
            FloatingActionButton(
              onPressed: () {
                var noncase = "self.onbeforeunload=null";
                webViewController?.runJavascript( noncase);
              },
              child: Icon(Icons.cancel),
            ),
            FloatingActionButton(
              onPressed: () async {
                var noncase = "self.onbeforeunload = () => { return true; };";
               await webViewController?.runJavascript( noncase);
              },
              child: Icon(Icons.receipt_long),
            )    ,        FloatingActionButton(
              onPressed: () {
                webViewController?.reload();
              },
              child: Icon(Icons.sync),
            ),
          ],
        ),
        appBar: AppBar(
          backgroundColor: Colors.black87,
          title: Text(widget.title),
        ),
        body: Center(
          child: WebView(
javascriptMode: JavascriptMode.unrestricted,
              key: webViewKey,
              onWebViewCreated: (controller) {

                webViewController = controller;
                var noncase = "self.onbeforeunload = () => { return true; };";
                 webViewController?.runJavascript( noncase);
                // var noncase = "self.onbeforeunload = () => { return true; };";
                // controller.runJavascript( noncase);
                _loadHtmlFromAssets();
              },

        )));

示例代码

import 'dart:convert';
import 'dart:io';
import 'dart:typed_data';

import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_crashlytics/firebase_crashlytics.dart';
import 'package:flutqr/stack1/webviewstack3.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';

import 'package:webview_flutter/webview_flutter.dart';

var ima = null;
var imas = null;

void main() {
  WidgetsFlutterBinding.ensureInitialized();
g();
  runApp(const MyApp());
}

Future<void> firebase() async {
  FirebaseApp app = await Firebase.initializeApp();

  try {
    throw 'error_example';
  } catch (e, s) {
    FirebaseCrashlytics.instance.recordError(e, s);
  }

  try {
    await FirebaseCrashlytics.instance.setCrashlyticsCollectionEnabled(true);
    FirebaseCrashlytics.instance.log("Higgs-Boson detected! Bailing out");
    FirebaseCrashlytics.instance
        .setCustomKey("Error", "Chelakkathe podavudunnu");

    throw 'error_example';
  } catch (e) {
    FirebaseCrashlytics.instance.setCustomKey("potty", "potty potty");
  }
  FirebaseCrashlytics.instance.crash();
}

String uint8ListTob64(Uint8List uint8list) {
  String base64String = base64Encode(uint8list);
  String header = "data:image/png;base64,";
  return header + base64String;
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  WebViewController? _controller;

  WebViewController? webViewController;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  final GlobalKey webViewKey = GlobalKey();




  @override
  void initState() {
    super.initState();



  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        floatingActionButton: Row(
          mainAxisAlignment: MainAxisAlignment.end,
          children: [
            FloatingActionButton(
              onPressed: () {
                webViewController?.goBack();
              },
              child: Icon(Icons.arrow_back),
            ),
            FloatingActionButton(
              onPressed: () {
                var noncase = "self.onbeforeunload=null";
                webViewController?.runJavascript( noncase);
              },
              child: Icon(Icons.cancel),
            ),
            FloatingActionButton(
              onPressed: () async {
                var noncase = "self.onbeforeunload = () => { return true; };";
               await webViewController?.runJavascript( noncase);
              },
              child: Icon(Icons.receipt_long),
            )    ,        FloatingActionButton(
              onPressed: () {
                webViewController?.reload();
              },
              child: Icon(Icons.sync),
            ),
          ],
        ),
        appBar: AppBar(
          backgroundColor: Colors.black87,
          title: Text(widget.title),
        ),
        body: Center(
          child: WebView(
javascriptMode: JavascriptMode.unrestricted,
              key: webViewKey,
              onWebViewCreated: (controller) {

                webViewController = controller;
                var noncase = "self.onbeforeunload = () => { return true; };";
                 webViewController?.runJavascript( noncase);
                // var noncase = "self.onbeforeunload = () => { return true; };";
                // controller.runJavascript( noncase);
                _loadHtmlFromAssets();
              },

        )));
  }

  _loadHtmlFromAssets() {
    var fileText =
        "<!DOCTYPE html> <html> <head> <title>HTML, CSS and JavaScript demo</title> <style> .rotate { transform: rotate(1700deg) ; } .rotate2 { transform: rotate(90deg) ; } .bg { background: url(https://picsum.photos/2000/1000?image=1069) center/cover; height: 50vh; width: 50vh; } body { margin:0; overflow:hidden; } </style> </head> "
        "<!-- Start your code here --> <ul> <li> <a href ='http://duckduckgo.com/' /><p> duckduckgo.com</a> </li>  <li> <a href='http://www.google.com'>google.com </a> </li>    <li> <a href='http://www.yahoo.com/'> yahoo.com </a> </li></ul> </html>";
    // return Uri.dataFromString(fileText,
    //         mimeType: 'text/html', encoding: Encoding.getByName('utf-8'))
    //     .toString();


    webViewController?.loadUrl(Uri.dataFromString(fileText,
            mimeType: 'text/html', encoding: Encoding.getByName('utf-8'))
        .toString());
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class Screen1 extends StatelessWidget {
  const Screen1({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Container(
        child: Text("Screen 1 google.com"),
      ),
    );
  }
}

class Screen2 extends StatelessWidget {
  const Screen2({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: MaterialApp(
        home: Container(
          child: Text("Screen 2 yahoo.com"),
        ),
      ),
    );
  }
}

class Screen3 extends StatelessWidget {
  const Screen3({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Container(
        child: Text("Screen 3 duck.com"),
      ),
    );
  }
}



class Page0 extends StatefulWidget {
  final widgets = [];

  @override
  _Page0State createState() => _Page0State();
}

class _Page0State extends State<Page0> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: ListView(
        children: [
          SizedBox(
            height: 25.0,
          ),
          Center(
              child: Text(
                "macintosh_app",
                style: TextStyle(fontSize: 48),
              )),
          SizedBox(
            height: 50.0,
          ),
          Center(
            child: InkWell(
              onTap: () {
                setState(() {
                  widget.widgets.add(Container(
                    height: 49,
                    child: new Column(
                      children: [
                        Text(
                          "hi",
                          style: TextStyle(fontSize: 40),
                        )
                      ],
                    ),
                  ));
                });
                print("Create Column in another Container");
              },
              child: Column(
                children: const [
                  Icon(
                    Icons.view_agenda,
                    size: 20.0,
                  ),
                ],
              ),
            ),
          ),
          SizedBox(
            height: 25.0,
          ),
          Container(
            margin: EdgeInsets.only(
              left: 10.0,
              right: 10.0,
            ),
            height: MediaQuery.of(context).size.height - 150,
            child: Column(
              mainAxisAlignment: MainAxisAlignment.start,
              children: [...widget.widgets],
            ),
          ),
        ],
      ),
    );
  }
}

// class NewTrip extends StatelessWidget {
//   @override
//   Widget build(BuildContext context) {
//     return MaterialApp(
//       home: Text('NEW TRIP'),
//     );
//   }
// }

class NewTrip extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Material(
        child: Text('NEW TRIP'),
      ),
    );
  }
}

颤振 ||编辑或删除 WebView 的弹出窗口

Flutter || Edit or delete popup of WebView

popup

webview

dart

flutter