Create Alert Dialog with Radio Button in Android

In this post, we’ll be creating an alert dialog with a radio button using Material Design 2.0 in our Android apps with Kotlin.

Let’s Create Alert Dialog With Radio Button

Step 1:

Open Android Studio.
Create a new project or go to File- New Project.
Fill all details to create a new project.

Step 2:

First, you need to add the material components dependency in build.gradle

implementation 'com.google.android.material:material:1.3.0'

Step 3 :

Now open your res/layout/activity_main.xml. file and add the following code.

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 
    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">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="24dp"
        android:fontFamily="cursive"
        android:text="Radio Confirmation Dialog"
        android:textColor="@color/black"
        android:textSize="32sp"
        android:textStyle="bold"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btn_showDialog"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="276dp"
        android:text="Radio Confirmation Dialog"
        android:textAllCaps="false"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView" />
</androidx.constraintlayout.widget.ConstraintLayout>

Step 4:

After adding the XML file, now open your src/MainActivity.kt file and add the following code.

package com.techpassmaster.radioconfirmationdialog

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.Toast
import com.google.android.material.dialog.MaterialAlertDialogBuilder

/**
 * Created by Techpass Master on 09-May-21.
 * www.techpassmaster.com
 */

class MainActivity : AppCompatActivity() {
    private lateinit var selectedFruits: String
    private var selectedFruitsIndex: Int = 0
    private val fruits = arrayOf("Apple", "Banana", "Coconut", "Orange", "Pineapple", 
                                "Papaya", "Mango", "Blackberries", "Guava")
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val showDialog: Button = findViewById(R.id.btn_showDialog)
        // button click listener
        showDialog.setOnClickListener {
        
        // call to function
            showRadioConfirmationDialog()
        }
    }
    // fun for showing dialog with Radio Button
    private fun showRadioConfirmationDialog() {
        selectedFruits = fruits[selectedFruitsIndex]
        MaterialAlertDialogBuilder(this)
                .setTitle("List of Fruits")
                .setSingleChoiceItems(fruits, selectedFruitsIndex) { dialog_, which ->
                    selectedFruitsIndex = which
                    selectedFruits = fruits[which]
                }
                .setPositiveButton("Ok") { dialog, which ->
                    Toast.makeText(this, "$selectedFruits Selected", Toast.LENGTH_SHORT)
                            .show()
                }
                .setNegativeButton("Cancel") { dialog, which ->
                    dialog.dismiss()
                }
                .show()
    }
}

Step 5:

Let’s run and test the application. Connect your Android Mobile device with your computer and click to run from Android Studio. After successfully run your application, your application looks like this.