Kotlin Android WebView

Android WebView is a view component which displays the web pages in the application. It uses a WebKit engine to show the web pages. The android.webkit.WebView class is the subclass of AbsoluteLayout class.
The loadUrl() and loadData() methods of WebView are used to load and display the web pages. To learn more about Android WebView go to https://www.javatpoint.com/android-webview-example
There are different ways to load the web page in WebView such as:
Load the HTML content as a string in the class:

val wedData: String =  "< html>< body>< h1>Hello, Javatpoint!< /h1>< /body>< /html>"  
val mimeType: String = "text/html"  
val utfType: String = "UTF-8"  
webView.loadData(wedData,mimeType,utfType)  

Load the web page (.html, .jsp, etc.) from within the application. In such case, web pages are placed in assets directory.

webView.loadUrl("file:///android_asset/index.html")  

Load the web URL inside WebView as:

webView.loadUrl("https://www.javatpoint.com/")  

Kotlin Android WebView Example

In this example, we will load the web URL in the WebView component and override the URL.

Directory structure

activity_main.xml

Add the WebView component in the activity_main.xml file.

< ?xml version="1.0" encoding="utf-8"?>  
< LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    xmlns:app="http://schemas.android.com/apk/res-auto"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    tools:context="example.javatpoint.com.kotlinwebview.MainActivity">  
  
  
    < WebView  
        android:id="@+id/webView"  
        android:layout_width="fill_parent"  
        android:layout_height="fill_parent"/>  
< /LinearLayout>  

AndroidMenifest.xml

In the AndroidMenifest.xml file, add the Internet permission to connect the network connection.

< uses-permission android:name="android.permission.INTERNET"/>  
  
< ?xml version="1.0" encoding="utf-8"?>  
< manifest xmlns:android="http://schemas.android.com/apk/res/android"  
    package="example.javatpoint.com.kotlinwebview">  
    < 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>  

MainActivity.kt

Add the following code in the MainActivity.kt class. In this class, we are using the loadUrl() method of WebView to load web URL.
Create a MyWebViewClient class that extends the WebViewClient that override the shouldOverrideUrlLoading() method.

package example.javatpoint.com.kotlinwebview  
  
import android.app.Activity  
import android.os.Build  
import android.support.v7.app.AppCompatActivity  
import android.os.Bundle  
import android.support.annotation.RequiresApi  
import android.webkit.WebResourceError  
import android.webkit.WebResourceRequest  
import android.webkit.WebView  
import android.webkit.WebViewClient  
import android.widget.Toast  
import kotlinx.android.synthetic.main.activity_main.*  
  
class MainActivity : AppCompatActivity() {  
  
    override fun onCreate(savedInstanceState: Bundle?) {  
        super.onCreate(savedInstanceState)  
        setContentView(R.layout.activity_main)  
  
      /*  val wedData: String =  "< html>< body>< h1>Hello, Javatpoint!< /h1>< /body>< /html>" 
        val mimeType: String = "text/html" 
        val utfType: String = "UTF-8" 
        webView.loadData(wedData,mimeType,utfType)*/  
  
        /* val myWebUrl: String = "file:///android_asset/index.html" 
         webView.loadUrl(myWebUrl)*/  
  
        webView.webViewClient = MyWebViewClient(this)  
        webView.loadUrl("https://www.javatpoint.com/")  
    }  
    class MyWebViewClient internal constructor(private val activity: Activity) : WebViewClient() {  
  
        @RequiresApi(Build.VERSION_CODES.LOLLIPOP)  
        override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest?): Boolean {  
            val url: String = request?.url.toString();  
            view?.loadUrl(url)  
            return true  
        }  
  
        override fun shouldOverrideUrlLoading(webView: WebView, url: String): Boolean {  
            webView.loadUrl(url)  
            return true  
        }  
  
        override fun onReceivedError(view: WebView, request: WebResourceRequest, error: WebResourceError) {  
            Toast.makeText(activity, "Got Error! $error", Toast.LENGTH_SHORT).show()  
        }  
    }  
}