Android 01

             How to make your first application on android

• Thinks you required :
1. sdk
2. eclips

IF you r complete setup you can develop first application:

• this appellation contain 
• using of java
• using of xml file

About application:

• this simple app contain.when you click on button message is displayed as given in below picture.

Names :

• java file::MainActivity.java
• xml file::activity_main.xml

STEP 1:: activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="While click message displayes.." />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/textView1"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="15dp"
        android:text="Button" />

</RelativeLayout>

STEP 2:: MainActivity.java

package com.example.myfirstapp;

import android.os.Bundle;

import android.app.Activity;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

Button b1;

@Override

protected void onCreate(Bundle savedInstanceState){

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

b1=(Button)findViewById(R.id.button1);

b1.setOnClickListener(this);

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items to the action bar if it is present.

getMenuInflater().inflate(R.menu.main, menu);

return true;

}

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

Toast.makeText(this, "I am button which you clicked", Toast.LENGTH_LONG).show();

}

}

Here ends our 1 lesson.if you like then comment it.