Steps to Create My HelloWorld Program in Eclipse with Android SDK. Create a new android project. File->New->Android Project. Fill in information like Project Name, Location for your project (e.g. Create new project in workspace). Select build Target. Android has several Versions ranging from 1.1 to 2.0 (latest). Select the target platform you want to port your application to. I selected 1.5 and it depends on you. Enter Application Name, Package name, Activity Name and hit finish button. In my case I entered following information for my first HelloWorld Program.

ProjectName: HelloWorld
Location for your project: /home/sanjeev/androidworkspace/HelloWorld
Select Build Target: Android 1.5
Application Name: HelloWorld
Package Name: com.sanjeevshrestha.android
Activity Name: HelloWorld

This creates a project in your workspace and you are ready to modify the activity file that is HelloWorld.java which is in your src folder under the folder structure depending on your package name. In my case it is src/com/sanjeevshrestha/android/HelloWorld.java. Here is the content of my HelloWorld.java file

/**
* Hello World Program
* @author Sanjeev Shrestha
* @version 1.0
* @date 8 November 2009
*
*/

package com.sanjeevshrestha.android;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import java.util.Date;

public class HelloWorld extends Activity implements View.OnClickListener{
/** Called when the activity is first created. */
Button btn;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
btn=new Button(this);
btn.setOnClickListener(this);
updateTime();
setContentView(btn);
}

public void onClick(View view)
{
updateTime();
}

public void updateTime()
{
String DateString=new Date().toString();
btn.setText(“Hello World by Sanjeev at “+DateString);
}
}

Build the project and your first HelloWorld program is ready for Android. Here is the output of my HelloWorld Program.

My First Android HelloWorld Program. I am loving it
Try for yourself and Happy Androiding!!

Download the zip file for HelloWorld application HelloWorld

sudo apt-get install openjdk-6-jre sun-java6-jdk
sudo update-java-alternatives -s java-6-sun

Note: update with the latest java version
This should work with other flavor of linux too. Try with appropriate package manager.

Now try installing the android sdk again. It should work. Happy androiding..

Earlier we had different platforms for mobile devices running different sets of applications. Hence mobile computing earlier had, in my view, limited its charm to few developers. But now everything is changing, everything is going mobile. The devices are powerful and internet is common in these devices. Android arrives here to bridge the gap between developers and mobile world with one common platform and rich sets of features.

Android, as of this post, is tagged a version 2.0 release. I am particularly interested in android because it is opensource and is a solution to one big problem “diverse devices, diverse platforms“. Open Handset Alliance and Google released Android to overcome this problem by providing a common platform for developers. The Open Handset Alliance is a group of hardware and software developers, including Google, NTT DoCoMo, Sprint Nextel, and HTC, whose goal is to create a more open cell phone environment. So friends Android is here to stay for long.

Android applications are developed using Java and can be ported rather easily to the new platform. Yes, only Java currently. If you are a Java Developer, Android is half battle won. If you are not a Java Developer, you should know at least a little Java to begin.

I created my first Hello World application yesterday and it feels great