packages/webview_flutter/example/lib/main.dart

// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

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

void main() => runApp(MaterialApp(home: WebViewExample()));

class WebViewExample extends StatelessWidget {
  final Completer<WebViewController> _controller =
      Completer<WebViewController>();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Flutter WebView example'),
        // This drop down menu demonstrates that Flutter widgets can be shown over the web view.
        actions: <Widget>[
          NavigationControls(_controller.future),
          const SampleMenu(),
        ],
      ),
      body: WebView(
        initialUrl: 'https://flutter.io',
        javaScriptMode: JavaScriptMode.unrestricted,
        onWebViewCreated: (WebViewController webViewController) {
          _controller.complete(webViewController);
        },
      ),
    );
  }
}

class SampleMenu extends StatelessWidget {
  const SampleMenu();

  @override
  Widget build(BuildContext context) {
    return PopupMenuButton<String>(
      onSelected: (String value) {
        Scaffold.of(context)
            .showSnackBar(SnackBar(content: Text('You selected: $value')));
      },
      itemBuilder: (BuildContext context) => <PopupMenuItem<String>>[
            const PopupMenuItem<String>(
              value: 'Item 1',
              child: Text('Item 1'),
            ),
            const PopupMenuItem<String>(
              value: 'Item 2',
              child: Text('Item 2'),
            ),
          ],
    );
  }
}

class NavigationControls extends StatelessWidget {
  const NavigationControls(this._webViewControllerFuture)
      : assert(_webViewControllerFuture != null);

  final Future<WebViewController> _webViewControllerFuture;

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<WebViewController>(
      future: _webViewControllerFuture,
      builder:
          (BuildContext context, AsyncSnapshot<WebViewController> snapshot) {
        final bool webViewReady =
            snapshot.connectionState == ConnectionState.done;
        final WebViewController controller = snapshot.data;
        return Row(
          children: <Widget>[
            IconButton(
              icon: const Icon(Icons.arrow_back_ios),
              onPressed: !webViewReady
                  ? null
                  : () async {
                      if (await controller.canGoBack()) {
                        controller.goBack();
                      } else {
                        Scaffold.of(context).showSnackBar(
                          const SnackBar(content: Text("No back history item")),
                        );
                        return;
                      }
                    },
            ),
            IconButton(
              icon: const Icon(Icons.arrow_forward_ios),
              onPressed: !webViewReady
                  ? null
                  : () async {
                      if (await controller.canGoForward()) {
                        controller.goForward();
                      } else {
                        Scaffold.of(context).showSnackBar(
                          const SnackBar(
                              content: Text("No forward history item")),
                        );
                        return;
                      }
                    },
            ),
          ],
        );
      },
    );
  }
}