About Me: PackageInfo.versionName and PackageInfo.versionCode

PackageManager is a class for retrieving various kinds of information related to the application packages that are currently installed on the device. You can find this class through getPackageManager(). And PackageInfo hold the overall information about the contents of a package. This corresponds to all of the information collected from AndroidManifest.xml.



The information of android:versionCode and android:versionName in AndroidManifest.xml can be retrieved from PackageInfo.versionName and PackageInfo.versionCode.

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:orientation="vertical"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   >
<TextView 
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="@string/hello"
   />
<LinearLayout
   android:orientation="vertical"
   android:gravity="bottom"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   >
<Button 
   android:id="@+id/aboutme"
   android:layout_gravity="center_horizontal"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:text="- About Me -"
   />
</LinearLayout>
</LinearLayout>

AndroidAboutMe.java

package com.exercise.AndroidAboutMe;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class AndroidAboutMe extends Activity {
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
       Button buttonAboutMe = (Button)findViewById(R.id.aboutme);
      
       buttonAboutMe.setOnClickListener(new Button.OnClickListener(){

  @Override
  public void onClick(View v) {
   // TODO Auto-generated method stub
  
   String strVersion;
  
   PackageInfo packageInfo;
   try {
    packageInfo = getPackageManager().getPackageInfo(getPackageName(), 0);
    strVersion = "Version Name: " + packageInfo.versionName +"\n"
       + "Version Code: " + String.valueOf(packageInfo.versionCode);
   } catch (NameNotFoundException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    strVersion = "Cannot load Version!";
   } 
  
   new AlertDialog.Builder(AndroidAboutMe.this)
   .setTitle("About Me!").setMessage(strVersion)
   .setPositiveButton("OK",
    new DialogInterface.OnClickListener() {
     public void onClick(DialogInterface dialog, int which) {}
     }).show();
  }});
   }
}

Download the files.