在Android和iOS上从后台恢复应用程序后，inappwebview上出现白屏

当我关闭应用程序大约一分钟，然后在恢复之前将其移动到后台时，InAppWebView小部件被白色覆盖，或者它只是不显示屏幕上的Web内容.我仍然可以与应用程序暂停之前加载的页面进行交互，我可以听到网站上播放的声音效果，所以它肯定在某种程度上仍然处于活动状态.我只是对如何在恢复应用程序时让它真正显示页面感到困惑.当我重新打开挂起的应用程序时，调试控制台没有显示任何异常;它与InAppWebView实际可见时的输出完全相同.

我试着在我的应用程序中实现了InAppWebView的基本实现，使用了不同的URL，运行Ffltter Clear，运行FightPub升级，运行Ffltter Pub降级，但我仍然遇到这个问题.以下是该页面的代码.

class CustomWebView extends StatefulWidget {
  final String url;

  CustomWebView({required this.url});

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

class _CustomWebViewState extends State<CustomWebView>
    with SingleTickerProviderStateMixin, WidgetsBindingObserver {
  bool _isLoading = true; // Initially, webview is loading
  late InAppWebViewController webcontroller;

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

  @override
  Widget build(BuildContext context) {
    return InAppWebView(
      key: Key('webview'),
      initialOptions: InAppWebViewGroupOptions(
        crossPlatform: InAppWebViewOptions(
          transparentBackground: true,
          useShouldOverrideUrlLoading: true,
          supportZoom: true,
        ),
        android: AndroidInAppWebViewOptions(
          builtInZoomControls: true,
          loadWithOverviewMode: true,
          useWideViewPort: true,
        ),
        ios: IOSInAppWebViewOptions(
          disableInputAccessoryView: true,
          allowsInlineMediaPlayback: true,
        ),
      ),
      initialUrlRequest: URLRequest(url: Uri.parse(widget.url)),
      shouldOverrideUrlLoading: (controller, navigationAction) async {
        var uri = navigationAction.request.url!;
        if (uri.toString().contains('logout')) {
          logOut(context);
          return NavigationActionPolicy.CANCEL;
        }
        if (uri.toString().contains('whatsapp')) {
          var shareText = await getTextParam(uri.toString());
          Share.share(shareText!);
          return NavigationActionPolicy.CANCEL;
        }
        if (uri.toString().contains('?process_s=3')) {
          var status = await Permission.storage.status;
          if (!status.isGranted) {
            status = await Permission.storage.request();
          }
          if (status.isGranted) {
            Navigator.push(
                context,
                MaterialPageRoute(
                    builder: (context) => GenerateQRPage(
                          url: '',
                        )));
          }
          return NavigationActionPolicy.CANCEL;
        }

        return NavigationActionPolicy.ALLOW;
      },
      onWebViewCreated: (InAppWebViewController controller) {
        webcontroller = controller;
      },
      onLoadStop: (controller, url) async {},
    );
  }
}