Android - setOnCheckedChangeListener for checkbox

Android | CheckBox.setOnCheckedChangeListener() Method: In this tutorial, we will learn how to work with the setOnCheckedChangeListener method for checkboxes in Android. By Manu Jemini Last updated : June 06, 2023

Android CheckBox.setOnCheckedChangeListener() Method

While working with setOnCheckedChangeListener method in Android we and implement a listener with each checkbox which give us a callback function for each of them.

setOnCheckedChangeListener is a method in android basically used with checkboxes, radio button etc. You can initiate this method easily like,

Syntax

public void setOnCheckedChangeListener(new CompoundButton. OnCheckedChangeListener)

While invoking this method a callback function will run. You can also initiate a class for more than one listener, so this can lead you to code reusability.

After making the class you can implement CompoundButton.OnCheckedChangeListener{} method which gives you an override method inherited from superclass called onCheckedChanged(CompoundButton buttonView, boolean isChecked){} in which you can easily implement your code and it also gives you a button view and a Boolean isChecked() method.

Android CheckBox.setOnCheckedChangeListener() Example

Java file


package com.example.hp.demo;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    CheckBox Product1,Product2,Product3;

    TextView amount;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Product1=(CheckBox)findViewById(R.id.chkp1);
        Product2=(CheckBox)findViewById(R.id.chkp2);
        Product3=(CheckBox)findViewById(R.id.chkp3);

        amount=(TextView)findViewById(R.id.amount);

        Product1.setOnCheckedChangeListener(new Chk_class());
        Product2.setOnCheckedChangeListener(new Chk_class());
        Product3.setOnCheckedChangeListener(new Chk_class());
    }
    class Chk_class implements CompoundButton.OnCheckedChangeListener{

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

            int amt=0;
            if(Product1.isChecked())
            {
                amt=amt+1000;
            }
            if(Product2.isChecked())
            {
                amt=amt+2000;
            }
            if(Product3.isChecked())
            {
                amt=amt+3000;
            }
            amount.setText(amt+"Rs.");
        }
    }
}

XML file


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:weightSum="1">

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Product 1(1000 Rs.)"
        android:id="@+id/chkp1"
        android:checked="false" />

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Product 2(2000 Rs.)"
        android:id="@+id/chkp2"
        android:checked="false" />

    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Product 3(3000 Rs.)"
        android:id="@+id/chkp3"
        android:checked="false" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/amount"
        android:layout_weight="0.16"
        android:hint="amount" />
</LinearLayout>

Manifest file


<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.hp.demo">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>