how to use webview with progressbar

AndroidWebVIewWithProgressBar.doc

//activity_main.xml
<?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"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <ProgressBar
        android:layout_width="match_parent"
        android:layout_height="10dp"
        android:id="@+id/progressbar"
        style="?android:attr/progressBarStyleHorizontal"

        android:progress="20"
        android:visibility="gone"/>

    <WebView
        android:id="@+id/webview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />


</LinearLayout>

//main.java
      public class MainActivity extends AppCompatActivity {
        WebView webView;
        String url="https://www.google.co.in/";
        ProgressBar progressBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //hide action bar
        getSupportActionBar().hide();
        //connect object with activity
        progressBar=findViewById(R.id.progressbar);
        webView=findViewById(R.id.webview);
        WebSettings webSettings = webView.getSettings();
        webSettings.setJavaScriptEnabled(true);
        //load url to webview
         webView.loadUrl(url);
         //open links inside activitys
            webView.setWebViewClient(new WebViewClient(){
                @Override
                public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
                    view.loadUrl(request.getUrl().toString());
                    return super.shouldOverrideUrlLoading(view, request);
                }
            });
            //get page loaded progress
            webView.setWebChromeClient(new WebChromeClient(){
                @Override
                public void onProgressChanged(WebView view, int newProgress) {
                    progressBar.setVisibility(View.VISIBLE);
                    progressBar.setProgress(newProgress);
                    if (newProgress==100){
                        progressBar.setVisibility(View.GONE);
                    }
                    super.onProgressChanged(view, newProgress);

                }
            });
            
            }
            //go to previous page
             @Override
    public void onBackPressed() {
        if (webView.canGoBack()){
            webView.goBack();
        }
        else{
            super.onBackPressed();
        }
    }
    
    }