FullScreenWebChromeClient.kt

//     REMEMBER TO ADD FOLLOWING TO YOUR ACTIVITY
//     android:configChanges="orientation|screenSize|keyboardHidden"

import android.app.Activity
import android.content.pm.ActivityInfo
import android.graphics.Bitmap
import android.view.View
import android.view.ViewGroup
import android.webkit.WebChromeClient
import android.webkit.WebView
import android.webkit.WebViewClient
import android.widget.FrameLayout

class FullScreenWebChromeClient(
    private val activity: Activity
) : WebChromeClient() {

    private val FULL_SCREEN_SETTING = View.SYSTEM_UI_FLAG_FULLSCREEN or
            View.SYSTEM_UI_FLAG_HIDE_NAVIGATION or
            View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION or
            View.SYSTEM_UI_FLAG_LAYOUT_STABLE or
            View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN or
            View.SYSTEM_UI_FLAG_IMMERSIVE

    private var mCustomView: View? = null
    private var mCustomViewCallback: CustomViewCallback? = null
    private var mOriginalOrientation = 0
    private var mOriginalSystemUiVisibility = 0

    override fun onHideCustomView() {
        (activity.window.decorView as FrameLayout).removeView(mCustomView)
        mCustomView = null
        activity.window.decorView.systemUiVisibility = mOriginalSystemUiVisibility
        activity.requestedOrientation = mOriginalOrientation
        mCustomViewCallback?.onCustomViewHidden()
        mCustomViewCallback = null
        activity.requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT
    }

    override fun onShowCustomView(
        paramView: View,
        paramCustomViewCallback: CustomViewCallback
    ) {
        if (mCustomView != null) {
            onHideCustomView()
            return
        }
        mCustomView = paramView
        mOriginalSystemUiVisibility = activity.window.decorView.systemUiVisibility
        mOriginalOrientation = activity.requestedOrientation
        mCustomViewCallback = paramCustomViewCallback
        (activity.window.decorView as FrameLayout)
            .addView(
                mCustomView,
                FrameLayout.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT,
                    ViewGroup.LayoutParams.MATCH_PARENT
                )
            )
        activity.window.decorView.systemUiVisibility = FULL_SCREEN_SETTING
        activity.requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE
        mCustomView!!.setOnSystemUiVisibilityChangeListener { updateControls() }
    }

    override fun getDefaultVideoPoster(): Bitmap? {
        return Bitmap.createBitmap(10, 10, Bitmap.Config.ARGB_8888)
    }
    
    @SuppressLint("SetJavaScriptEnabled")
    fun initWebView(webView: WebView, url: String) {
        webView.visibility = View.VISIBLE
        webView.webViewClient = WebViewClient()
        webView.webChromeClient = this
        webView.settings.javaScriptEnabled = true
        webView.loadUrl(url)
    }

    private fun updateControls() {
        mCustomView?.let {
            val params = it.layoutParams as FrameLayout.LayoutParams
            params.bottomMargin = 0
            params.topMargin = 0
            params.leftMargin = 0
            params.rightMargin = 0
            params.height = ViewGroup.LayoutParams.MATCH_PARENT
            params.width = ViewGroup.LayoutParams.MATCH_PARENT
            it.layoutParams = params
            activity.window.decorView.systemUiVisibility = FULL_SCREEN_SETTING
        }
    }
}