Android RadioButton Example Kotlin

A RadioButton is a widget that belongs to the RadioGroup class and is designed to provide a set of mutually exclusive choices to the user. The user can only select her one option from a group of RadioButton elements.

Here is the tutorial for Java

Here is a simple example of using RadioButton in an Android app.

There Are Some Common Attributes for RadioButton

Step 1:

File open res/layout/activity_main.xml file −

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">



    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:layout_margin="10dp"
        android:orientation="vertical">

        <RadioGroup
            android:id="@+id/radioGroup"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <RadioButton
                android:id="@+id/radio_mango"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Mango" />

            <RadioButton
                android:id="@+id/radio_banana"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Banana" />

            <Button
                android:id="@+id/buttonSubmit"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Submit" />

            <TextView
                android:id="@+id/textResult"
                android:gravity="center"
                android:layout_marginTop="10dp"
                android:textSize="18dp"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Result" />


        </RadioGroup>
    </LinearLayout>




</RelativeLayout>

Step 2:

File open com.microappvalley.newtestproject/MainActivity.kt file −

package com.microappvalley.newtestproject

import android.os.Bundle
import android.widget.Button
import android.widget.RadioButton
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {
   var radioButtonData=""
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val buttonSubmit: Button =findViewById(R.id.buttonSubmit)
        val radio_mango: RadioButton =findViewById(R.id.radio_mango)
        val radio_banana: RadioButton =findViewById(R.id.radio_banana)
        val textResult: TextView =findViewById(R.id.textResult)

        radio_mango.setOnCheckedChangeListener { compoundButton, isChecked ->
            if (isChecked){
                radioButtonData="Mango";
                Toast.makeText(this@MainActivity, "Mango Button "+isChecked, Toast.LENGTH_SHORT).show();
            }
        }

        radio_banana.setOnCheckedChangeListener { compoundButton, isChecked ->
            if (isChecked){
                radioButtonData="Banana";
                Toast.makeText(this@MainActivity, "Banana Button "+isChecked, Toast.LENGTH_SHORT).show();
            }
        }

        buttonSubmit.setOnClickListener {

            textResult.text=radioButtonData
            Toast.makeText(this@MainActivity, radioButtonData, Toast.LENGTH_SHORT).show();        }
    }
}

Output: