How to open downloaded html files using localhost server in flutter?

I have a zip file to download. After it has been downloaded, I save it in External Storage (/storage/emulated/0/Android/data/…). I want to show a html page from the storage.

How to show the html page inside webview using localhost server? I also want to load other folders from the downloaded zip file.

I’ve tried using inappwebview but it can’t load local html file from external storage.

I’ve also implemented an example based on this reference link: https://stackoverflow.com/a/62529396/8091645

but in the above example we have to mention the file path in pubspec.yaml.

Instead of that I need a way were I do not have to add any file path in pubspec.yaml and using the localhostserver it should open the files from downloaded folder.