当有最终的 Completer 时，如何让我注入的 javascript 代码出现？

Question

嗨，我是 Flutter 的新手，这是我完成第一个应用程序时唯一剩下的问题，由于某种原因，我使用的注入 javascript 没有出现在 WebView 应用程序中。

FIXED (sorry for the delayed edit: the code was (await _controller.future).evaluateJavascript("document.getElementsByClassName('footer-container')[0].style.display='none';")

Note: Im using the webview_flutter by the flutter dev team and I want to have BOTH refresh FAB and injected code working at the same time

我的代码如下：

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

class HomePage extends StatefulWidget {
  HomePage({Key key}) : super(key: key);

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

class _HomePageState extends State<HomePage> {

  WebViewController _myController;
      final Completer<WebViewController> _controller =
      Completer<WebViewController>();
  @override
  Widget build(BuildContext context) {
    return SafeArea(
            child: Scaffold(
                  body: WebView(
                  initialUrl: 'https://syncshop.online/en/',
                  javascriptMode: JavascriptMode.unrestricted,
                  onWebViewCreated: (controller) {
                  _controller.complete(controller);
                },
          onPageFinished: (controller) {
          _myController.evaluateJavascript("document.getElementsByClassName('footer-container')[0].style.display='none';");
          },
          ),
    floatingActionButton: FutureBuilder<WebViewController>(
        future: _controller.future,
        builder: (BuildContext context, AsyncSnapshot<WebViewController> controller) {
          if (controller.hasData) {
            return FloatingActionButton(
            onPressed: () {
              controller.data.reload();
            },
            child: Icon(Icons.refresh),
          );
          }
          return Container();
        }),
          ),
      );
    }
}

Answer 1

我认为，_myController 没有分配任何东西。

所以，请尝试使用 _controller 代替 evaluateJavascript()。像这样：

(await _controller.future).evaluateJavascript("document.getElementsByClassName('footer-container')[0].style.display='none';");

当有最终的 Completer 时，如何让我注入的 javascript 代码出现？

How do I make my injected javascript code appear when theres a final Completer?

flutter

flutter-dependencies

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