Android Program

Activity.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:gravity="fill_vertical"

    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="match_parent"

        android:layout_height="wrap_content"

        android:gravity="center"

        android:text="@string/hello_world"

        android:textSize="30sp" />

    <Button

        android:id="@+id/addButtonn"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/textView1"

        android:layout_below="@+id/textView1"

        android:layout_marginTop="15dp"

        android:text="@string/Add" />

    <Button

        android:id="@+id/subButtonn"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/addButtonn"

        android:layout_below="@+id/addButtonn"

        android:layout_marginTop="18dp"

        android:text="@string/Sub" />

     <TextView

         android:id="@+id/textView2"

         android:layout_width="match_parent"

         android:layout_height="wrap_content"

         android:layout_alignLeft="@+id/subButtonn"

         android:layout_below="@+id/subButtonn"

         android:layout_marginTop="28dp"

         android:gravity="right"

         android:text="@string/present"

          />

   

</RelativeLayout>

Activity_main.java

package com.example.addsubtract;

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.TextView;

public class MainActivity extends Activity {

                int counter;

                Button add,sub;

                TextView tv;

                @Override

                protected void onCreate(Bundle savedInstanceState) {

                                super.onCreate(savedInstanceState);

                                setContentView(R.layout.activity_main);

                                counter=0;

                                tv=(TextView)findViewById(R.id.textView1);

                                add=(Button)findViewById(R.id.addButtonn);

                                sub=(Button)findViewById(R.id.subButtonn);

                                add.setOnClickListener(new OnClickListener() {

                                               

                                                @Override

                                                public void onClick(View arg0) {

                                                                // TODO Auto-generated method stub

                                                                counter++;

                                                                tv.setText("Your Result is"+counter);

                                                               

                                                }

                                });

                                sub.setOnClickListener(new OnClickListener() {

                                               

                                                @Override

                                                public void onClick(View arg0) {

                                                                // TODO Auto-generated method stub

                                                                counter--;

                                                                tv.setText("Your Result is "+counter);

                                                               

                                                }

                                });

                }

                @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;

                }

}

AndroidMainFest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.example.addsubtract"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="17" />

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.example.addsubtract.MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

</manifest>

 Strings.xml

<?xml version="1.0" encoding="utf-8"?>

<resources>

    <string name="app_name">AddSubtract</string>

    <string name="action_settings">Settings</string>

    <string name="hello_world">Your Total is  0</string>

    <string name="Add">Add By One</string>

    <string name="Sub">Sub By One</string>

    <string name="present">Presented By Ashok</string>

</resources>