[webview_flutter] Fix the issue that webview cannot load assets html and local html

[asjqkkkk]

Fix flutter/flutter#27086

Now, flutter webview can load html file in two ways:

Assetfiles

    WebView(
      onWebViewCreated: (WebViewController controller) {
        final url = 'assets/index.html';
        controller.loadAssetHtmlFile(url);
      },
      javascriptMode: JavascriptMode.unrestricted,
    );

Localfiles

    WebView(
      onWebViewCreated: (WebViewController controller) {
        controller.loadLocalHtmlFile(filePath)
      },
      javascriptMode: JavascriptMode.unrestricted,
    );

  Future<void> downloadFile(String url) async {
    Dio dio = Dio();
    String path = (await getApplicationDocumentsDirectory()).path;
    String fileName=url.substring(url.lastIndexOf("/")+1);
    await Dio().download(url, '$path/$fileName',onReceiveProgress: (rec,total){
      progress = ((rec/total) * 100).floor();
      if(progress >= 100){
        filePath= '$path/$fileName';
      }
      setState(() {});
    });
  }

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[asjqkkkk]

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[miyakeryo]

Could you support initialUrl? Because a black background page flickers for a moment.

[asjqkkkk]

Could you support initialUrl? Because a black background page flickers for a moment.

support initialUrl will bring some broken changes, this is not good for maintenance and expansion, so I didn't do that

maybe you can use some other way to load webview?

  String _urlPath;

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: _urlPath == null ? buildLoadingWidget(): buildWebView(),
    );
  }

[miyakeryo]

@asjqkkkk
Thanks for your suggestion. I solved this problem by using about:blank

[SetNameHere]

Hi,
does anyone know when this feature will be available?
It seems to be a great solution for one of my biggest problems.

Thanks for all your work!

[TheOneWithTheBraid]

Does anyone know if this will be merged in further releases?

[eric8words]

Any ETA for the merged release ?

[cyanglaz]

cc @bparrishMines

[Wian-TMC]

Possible ETA?

[Wian-TMC]

The PR Triage has last been updated on 13 August. Is there a more up to date indication when this will be available on the master branch?

[jamesdixon]

@asjqkkkk why did you end up closing this?

[asjqkkkk]

@asjqkkkk why did you end up closing this?

My branch was not updated for too many days, so I think there should be another fresh pr to fix this issue

[Wian-TMC]

@asjqkkkk The master branch has fixed major issues especially regarding the keyboard and is now out of the developers preview. While we wait for the PR, Is it maybe possible for you to create a new temporary fork from the latest master branch and re-add your asset loading implementation? This would be of great help

[DineshKachhot]

Local html file is loading but local assts like image and css are still not loading in Flutter 2.2 stable.