"onShowFileChooser" в моем приложении kotlin не работает

Question

Приложение работает правильно Но когда вы нажимаете кнопку «Загрузить файл» на страницах сайта, окно выбора файла не появляется бутон загрузки - нормальный ввод. и это работает в обычном браузере поэтому мне нужен пример кода, чтобы мое веб-представление могло получать файлы с устройства, когда участники нажимают кнопку «загрузить».

Приложение заранее получило права доступа к памяти

 <uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

мой идентификатор веб-просмотра = webframe

lateinit var mAdView: AdView

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    supportRequestWindowFeature(Window.FEATURE_NO_TITLE)
    setContentView(R.layout.activity_main)
    setSupportActionBar(toolbar)

    fab.setOnClickListener {
        webframe.reload()
    }

    val toggle = ActionBarDrawerToggle(
        this, drawer_layout, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close
    )
    drawer_layout.addDrawerListener(toggle)
    toggle.syncState()

    nav_view.setNavigationItemSelectedListener(this)

    //Admob
    MobileAds.initialize(this, getString(R.string.Admob_App_Id))
    mAdView = findViewById(R.id.adView)
    val adRequest = AdRequest.Builder().build()
    mAdView.loadAd(adRequest)

    //webframe
    webframe.loadUrl(getString(R.string.Site_Url))
    webframe.settings.javaScriptEnabled = true
    webframe.settings.allowFileAccess= true
    //Cach Settings
    webframe.settings.setAppCacheEnabled(true)
    webframe.settings.cacheMode = WebSettings.LOAD_DEFAULT
    webframe.settings.setAppCachePath("/data/data/$packageName/cache")
    webframe.webViewClient = callurlsin()
    //Upload Mathoud
    //Show Download
    webframe.setDownloadListener { url, userAgent, contentDisposition, mimeType, _ ->
        val request = DownloadManager.Request(Uri.parse(url))
        request.setMimeType(mimeType)
        request.addRequestHeader("cookie", CookieManager.getInstance().getCookie(url))
        request.addRequestHeader("User-Agent", userAgent)
        request.setDescription("يتم تحميل الملف...")
        request.setTitle(URLUtil.guessFileName(url, contentDisposition, mimeType))
        request.allowScanningByMediaScanner()
        request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
        request.setDestinationInExternalFilesDir(this@MainActivity, Environment.DIRECTORY_DOWNLOADS, ".png")
        val dm = getSystemService(Context.DOWNLOAD_SERVICE) as DownloadManager
        dm.enqueue(request)
        Toast.makeText(applicationContext, "يتم تحميل الملف", Toast.LENGTH_LONG).show()
    }
    //Befor And After Load Page
    webframe.webViewClient = object : WebViewClient(){
        override fun onReceivedError(view: WebView?, request: WebResourceRequest?, error: WebResourceError?) {
            webframe.loadUrl("file:///android_asset/404.html")
        }

        override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
            circel.visibility = View.VISIBLE
            super.onPageStarted(view, url, favicon)
        }

        override fun onPageFinished(view: WebView?, url: String?) {
            webframe.loadUrl("javascript:(function() { " +"document.getElementById('applink').style.display='none';})()")
            circel.visibility = View.INVISIBLE
            super.onPageFinished(view, url)
        }
    }
    //Disable Icons Colors
     nav_view.itemIconTintList = null
}//End

//back key to back
override fun onBackPressed() {
    if (drawer_layout.isDrawerOpen(GravityCompat.START)) {
        drawer_layout.closeDrawer(GravityCompat.START)
    } else {
        webframe.goBack()
    }
}

//laod urls in webview
class callurlsin : WebViewClient(){
    override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest?): Boolean {
        return false
    }
}

override fun onCreateOptionsMenu(menu: Menu): Boolean {
    // Inflate the menu; this adds items to the action bar if it is present.
    menuInflater.inflate(R.menu.main, menu)
    return true
}

override fun onOptionsItemSelected(item: MenuItem): Boolean {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    when (item.itemId) {
        R.id.Rating_App -> {
            webframe.loadUrl("https://play.google.com/store/apps/details?id=com.aradev.net")
        }
        R.id.Our_Apps -> {
            webframe.loadUrl("https://play.google.com/store/apps/developer?id=Mohamed+Slimane")
        }
    }
    return true
}

override fun onNavigationItemSelected(item: MenuItem): Boolean {
    // Handle navigation view item clicks here.
    when (item.itemId) {
        R.id.Home_Page ->{
            webframe.loadUrl("https://aradev.net")
        }
        R.id.profile -> {
            webframe.loadUrl("https://aradev.net/memberlist.php?mode=viewprofile&u=2")
        }
        R.id.notifications -> {
            webframe.loadUrl("https://aradev.net/ucp.php?i=ucp_notifications")

        }
        R.id.messages -> {
            webframe.loadUrl("https://aradev.net/ucp.php?i=pm&folder=inbox")
        }
        R.id.nav_manage -> {
            webframe.loadUrl("https://aradev.net/ucp.php")
        }
        R.id.actevated -> {
            webframe.loadUrl("https://aradev.net/search.php?search_id=active_topics")
        }

        R.id.nav_share -> {
            val sendIntent = Intent()
            sendIntent.action = Intent.ACTION_SEND
            sendIntent.putExtra(Intent.EXTRA_TEXT, getString(R.string.App_Link))
            sendIntent.type = "text/plain"
            startActivity(Intent.createChooser(sendIntent, "إرسال التطبيق"))

        }
        R.id.contact_us -> {
            webframe.loadUrl("https://aradev.net/memberlist.php?mode=contactadmin")
        }
    }

    drawer_layout.closeDrawer(GravityCompat.START)
    return true
}

}