Create a Toggle Button In Android

This is a sample activity which shows How to create a Toggle Button in android. Last topic published on this forum is Read Contacts from device.

Underlying Algorithm:

Basic description of algorithm in step by step form:
1.) Create a Project ToggleButtonDemo.
2.) Put the following code snippet in res/layout/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:id="@+id/tv" 
android:layout_width="fill_parent"android:layout_height="wrap_content" android:text="@string/hello" />
        <ToggleButton android:text="ToggleButton" android:id="@+id/toggleButton1"android:layout_width="wrap_content" android:layout_height="wrap_content"android:textOn="yello" android:textOff="red">
        </ToggleButton>
</LinearLayout>

3.) Run the application.

Steps to Create:

1.) Open Eclipse. Use the New Project Wizard and select Android Project Give the respective project name i.e. ToggleButtonDemo. Enter following information:
Project name: ToggleButtonDemo
Build Target: Android APIs2.1
Application name: ToggleButtonDemo
Package name: com.app.ToggleButtonDemo
Create Activity: ToggleButtonDemo

On Clicking Finish ToggleButtonDemo code structure is generated with the necessary Android Packages being imported along with ToggleButtonDemo.java. ToggleButtonDemo class will look like following:

package com.app.ToggleButtonDemo;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.TextView;
import android.widget.ToggleButton;

public class ToggleButtonDemo extends Activity implements OnClickListener
{
    ToggleButton tg;
    TextView tv;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        tv = (TextView) findViewById(R.id.tv);
        tv.setBackgroundColor(0xfff00000);
        tg = (ToggleButton) findViewById(R.id.toggleButton1);
        tg.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        if((tg.isChecked()))
        {
                System.out.println("checked");
                tv.setBackgroundColor(0xffffff00);
        }
        else
        {
                System.out.println("Unchecked");
                tv.setBackgroundColor(0xfff00000);
        }
    }
}

Output –The final output: