Example project to showcase how to load a local html file into a webview within an Android application
Mainly written because edent asked the question
Application consits of one Web View with the layout defined in app/src/main/res/layout/activity_main.xml, and an activity to load the html app/src/main/java/site/zpweb/webviewsample/MainActivity.kt.
The HTML file is stored in the asset folder app/src/main/assets
By loading the URL using the file schema relative linking to files within the asset folder "should" (untested) work just fine.
See WebView for more details.