Fill form programmatically in Android WebView in the background (Work manager)

Question

I am trying to create an app that programmatically fills a form and submits it while being in the background...

I have implemented it with web_view and it works perfectly but it's in an Activity but I want to do the same thing from the background.

As the web view is a UI element I don't know how to run it in a worker!

My code (works only when the app is open):

class MainActivity : ComponentActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            // Calling the composable function
            // to display element and its contents
            MainContent()
        }
    }
}

// Creating a composable
// function to display Top Bar
@Composable
fun MainContent() {
    Scaffold(
        topBar = { TopAppBar(title = { Text("WebView", color = Color.White) }, backgroundColor = Color(0xff0f9d58)) },
        content = { MyContent() }
    )
}


@SuppressLint("SetJavaScriptEnabled")
@Composable
fun MyContent(){
    val context = LocalContext.current
    // Declare a string that contains a url
//        val mUrl = "http:www.example.com"

    // Adding a WebView inside AndroidView
    // with layout as full screen
    AndroidView(factory = {
        WebView(it).apply {
            layoutParams = ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT
            )



            webViewClient = object: WebViewClient(){

                override fun onPageFinished(view: WebView?, url: String?) {
                    super.onPageFinished(view, url)


  evaluateJavascript("const inputList=document.querySelectorAll(\"input\");\n" +
            "inputList[0].value=\"00000\";\n" +
            "inputList[1].value=\"00000\";\n" +
            "inputList[2].click()", null)


                }

            }
            settings.javaScriptEnabled = true
            loadUrl(mUrl)
            //enable javascript



        }
    }, update = {
        it.loadUrl(mUrl)
    })
}

// For displaying preview in
// the Android Studio IDE emulator
@Preview(showBackground = true)
@Composable
fun DefaultPreview() {
    MainContent()
}

So my question is:

1. can I run the web-view in a worker (WorkManger) and how?

2. Is there any other way to do this without a web-view?

Answer 1

For my case Htmlunit-android worked perfectly ... It can browse the web in a headless mood and can submit forms.

exlample of form submiton:

private fun submittingForm() {
       
        val webClient = WebClient()

            // Get the first page
            val page1 = webClient.getPage<HtmlPage>("http://some_url")

            // Get the form that we are dealing with and within that form,
            // find the submit button and the field that we want to change.
            val form = page1.getFormByName("myform")
            val button = form.getInputByName<HtmlSubmitInput>("submitbutton")
            val textField = form.getInputByName<HtmlTextInput>("userid")

            // Change the value of the text field
            textField.type("root")

            // Now submit the form by clicking the button and get back the second page.
            val page2 = button.click<HtmlPage>()
        }