Don't navigate to other pages in WebView (shouldOverrideUrlLoading )

 ref: https://stackoverflow.com/questions/19426742/dont-navigate-to-other-pages-in-webview-disable-links-and-references

WebView gives developers an easy way to embed a web-based application to an Android app with almost no code. Just give it some URL and it works.

Implementation of the application which displays the predefined web page in a WebView is relatively straightforward.

        myWebView.loadUrl("your_pages");

There are two scenarios how a web app might react to a user click event. The first one is redirection. WebView client has quite an easy way to listen for redirects. You just need to override its method shouldOverrideUrlLoading() .

package com.demilion.myapp;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.os.Bundle;
import android.webkit.JavascriptInterface;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;

import java.io.IOException;
import android.content.res.AssetFileDescriptor;
import android.media.MediaPlayer;
import android.webkit.WebViewClient;

import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.ads.MobileAds;

public class MainActivity extends Activity {
    private AdView mAdView;
    private boolean loaded = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        MobileAds.initialize(this,
                "ca-app-pub-000000000000000~0000000000");

        mAdView = (AdView) findViewById(R.id.adView);
        AdRequest adRequest = new AdRequest.Builder().build();
        mAdView.loadAd(adRequest);

       WebView myWebView = (WebView) this.findViewById(R.id.webView);
       myWebView.setWebChromeClient(new WebChromeClient());

        myWebView.addJavascriptInterface(new WebAppInterface(this), "Android");

        myWebView.addJavascriptInterface(new AudioInterface(this), "AndAud");

        // Enable JavaScript
        WebSettings webSettings = myWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);


        //myWebView.loadUrl("https://codepen.io/loktar00/pen/CHpGo/");
        //myWebView.loadUrl("file:///android_asset/myhtml.html");
        myWebView.loadUrl("https://codepen.io/loktar00/pen/CHpGo/");



        myWebView.setWebViewClient(new WebViewClient(){
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {

                if(loaded == false){
                    view.loadUrl(url);
                    loaded = true;
                    return true;
                }else{
                    return false;
                }

            }
        });







    }

    public class WebAppInterface {

        Context context;

        /**
         * Instantiate the interface and set the context
         *
         * @param context
         */
        public WebAppInterface(Context context) {
            this.context = context;
        }

        /**
         * Show a dialog from the web page.
         *
         * @param message
         *            message of the dialog
         */
        @JavascriptInterface
        public void showDialog(String message) {

            // Use the Builder class for convenient dialog construction
            AlertDialog.Builder builder = new AlertDialog.Builder(this.context);
            builder.setMessage(message).setNeutralButton("OK",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            dialog.dismiss();
                        }
                    });
            // Create the AlertDialog object and return it
            builder.create().show();
        }
    }

    public class AudioInterface {
        Context mContext;

        AudioInterface(Context c) {
            mContext = c;
        }

        //Play an audio file from the webpage
        @JavascriptInterface
        public void playAudio(String aud) { //String aud - file name passed
            //from the JavaScript function
            final MediaPlayer mp;

            try {
                AssetFileDescriptor fileDescriptor =
                        mContext.getAssets().openFd(aud);
                mp = new MediaPlayer();
                mp.setDataSource(fileDescriptor.getFileDescriptor(),
                        fileDescriptor.getStartOffset(),
                        fileDescriptor.getLength());
                fileDescriptor.close();
                mp.prepare();
                mp.start();
            } catch (IllegalArgumentException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IllegalStateException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

}