Display AlertDialog for Latest Update of an Android Application

While using your smartphones you must have gone through a situation where an app asks the user to update it to use it further. Here, we are going to implement the same and see how an app asks users to update it by showing an update alert dialog.

What we are going to build in this application?

Here is a sample video of what we are going to implement in this application. Note that we are going to use java language for this project.

Step by Step Implementation

Step 1: Create a New Project

• Open a new project.
• We will be working on Empty Activity with language as Java. Leave all other options unchanged.
• Name the application at your convenience.
• There will be two default files named activity_main.xml and MainActivity.java.

If you don’t know how to create a new project in Android Studio then you can refer to How to Create/Start a New Project in Android Studio?

Step 2. Adding required dependency

Navigate to Gradle Scripts > gradle.scripts(module) and add the following dependency in it

implementation 'org.jsoup:jsoup:1.10.2'

Step 3. Adding Internet Permission

Navigate to the AndroidManifest.xml file and add the following permission to it-

<uses-permission android:name="android.permission.INTERNET"/>

Step 4. Working on XML file

Navigate to the app > res > layout > activity_main.xml and add the below code to that file. Below is the code for the activity_main.xml file.

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"
    android:gravity="center"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Current Version"
        android:textSize="32sp"/>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_current_version"
        android:textSize="32sp"
        android:textStyle="bold"
        android:layout_marginTop="4dp"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Latest Version"
        android:textSize="32sp"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/tv_latest_version"
        android:textSize="32sp"
        android:textStyle="bold"
        android:layout_marginTop="4dp"/>

</LinearLayout>

Step 5. Working on Java file

Navigate to the MainActivity.java file and use the following code in it. Comments are added to the code to have a better understanding.

Java

package com.example.updatealertdialog;

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

import android.content.DialogInterface;
import android.content.Intent;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.widget.TextView;

import org.jsoup.Jsoup;

import java.io.IOException;

public class MainActivity extends AppCompatActivity {

    // Initialize variables
    TextView tvCurrentVersion,tvLatestVersion;
    String sCurrentVersion,sLatestVersion;

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

        // Assign variables
        tvCurrentVersion=findViewById(R.id.tv_current_version);
        tvLatestVersion=findViewById(R.id.tv_latest_version);

        // Get latest version from play store
        new GetLatestVersion().execute();
    }

    private class GetLatestVersion extends AsyncTask<String,Void,String> {

        @Override
        protected String doInBackground(String... strings) {
            try {
                sLatestVersion= Jsoup
                        .connect("https://play.google.com//store/apps/details?id="
                        +getPackageName())
                        .timeout(30000)
                        .get()
                        .select("div.hAyfc:nth-child(4)>"+
                                "span:nth-child(2) > div:nth-child(1)"+
                                "> span:nth-child(1)")
                        .first()
                        .ownText();
            } catch (IOException e) {
                e.printStackTrace();
            }

            return sLatestVersion;
        }

        @Override
        protected void onPostExecute(String s) {
            // Get current version
            sCurrentVersion=BuildConfig.VERSION_NAME;
            // Set current version on Text view
            tvCurrentVersion.setText(sCurrentVersion);
            // Set latest version on TextView
            tvLatestVersion.setText(sLatestVersion);

            if(sLatestVersion != null)
            {
                // Version convert to float
                float cVersion=Float.parseFloat(sCurrentVersion);
                float lVersion=Float.parseFloat(sLatestVersion);

                // Check condition(latest version is
                  // greater than the current version)
                if(lVersion > cVersion)
                {
                    // Create update AlertDialog
                    updateAlertDialog();
                }
            }
        }
    }

    private void updateAlertDialog() {
        // Initialize AlertDialog
        AlertDialog.Builder builder=new AlertDialog.Builder(this);
        // Set title
        builder.setTitle(getResources().getString(R.string.app_name));
        // set message
        builder.setMessage("UUpdate Available");
        // Set non cancelable
        builder.setCancelable(false);

        // On update
        builder.setPositiveButton("Update", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                // Open play store
                startActivity(new Intent(Intent .ACTION_VIEW,
                        Uri.parse("market://details?id"+getPackageName())));
                // Dismiss alert dialog
                dialogInterface.dismiss();
            }
        });

        // on cancel
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                // cancel alert dialog
                dialogInterface.cancel();
            }
        });

        // show alert dialog
        builder.show();
    }
}

Here is the final output of our application.

Output: