在 Flutter 中打开 Web 视图并单击下拉列表时崩溃

Question

[ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: 'package:flutter/src/widgets/page_view.dart': Failed assertion: line 179 pos 7: 'positions.isNotEmpty': PageController.page cannot be accessed before a PageView is built with it.

new WebView(
                initialUrl: webUrl,
                javascriptMode: JavascriptMode.unrestricted,
                onWebViewCreated: (controller) {
                  _myController = controller;
                },
                /*javascriptChannels: <JavascriptChannel>[
                  _toasterJavascriptChannel(context),
                ].toSet(),*/
                onPageFinished: (url) {
                  _myController.evaluateJavascript(
                      "console.log(document.documentElement.innerHTML);");

                  setState(() {
                    _loadedPage = true;
                  });
                },
              ),```

Answer 1

GestureDetector(
              child: WebviewScaffold(
                url: webUrl,
                withJavascript: true,
                withLocalStorage: true,
                persistentFooterButtons: <Widget>[
                  RaisedBtn(
                    onPressed: (){
                      waafiPaySpalshScreen();
                      flutterWebviewPlugin.dispose();
                    },
                    text: "Confirm",
                  )
                ],
              ),
            ),