How to listen for a WebView finishing loading a URL in Android using Kotlin?

This example demonstrates how to listen for a WebView finishing loading a URL in Android using Kotlin.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="4dp"
   tools:context=".MainActivity">
   <TextView
      android:id="@+id/textView"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:padding="5dp"
      android:textColor="#000000"
      android:textSize="24sp" />
   <WebView
      android:id="@+id/webView"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_above="@id/btnLoad"
      android:layout_below="@id/textView" />
   <Button
      android:id="@+id/btnLoad"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_alignParentBottom="true"
      android:text="Load URL" />
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.kt

import android.os.Bundle
import android.webkit.WebChromeClient
import android.webkit.WebView
import android.webkit.WebViewClient
import android.widget.Button
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
class MainActivity : AppCompatActivity() {
   lateinit var webView: WebView
   lateinit var textView: TextView
   private lateinit var btnLoad: Button
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
      textView = findViewById(R.id.textView)
      btnLoad = findViewById(R.id.btnLoad)
      webView = findViewById(R.id.webView)
      webView.webViewClient = WebViewClient()
      btnLoad.setOnClickListener {
         webView.webViewClient = object : WebViewClient() {
            override fun onPageFinished(view: WebView, weburl: String) {
               Toast.makeText(this@MainActivity, "Your WebView is Loaded....",
               Toast.LENGTH_LONG).show()
            }
         }
         webView.webChromeClient = object : WebChromeClient() {
            override fun onProgressChanged(view: WebView, newProgress: Int) {
               textView.text = "Page loading : $newProgress%"
               if (newProgress == 100) {
                  textView.text = "Page Loaded."
               }
            }
         }
         webView.loadUrl("https://www.tutorialspoint.com")
      }
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.q11">
   <uses-permission android:name="android.permission.INTERNET" />
   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click the Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen