Hello Reader! In this post, we are going to learn about how to create android radio button programmatically in kotlin. We will also learn how to add radio button in radio group dynamically.

Output

Tutorialwing Android Kotlin Dynamic Radio Button Output

Getting Started

At first, we will create an android application. Then, we will create radio button dynamically and use it in the application.

1. Creating New Project In Kotlin

Follow the steps below to create new project. Please ignore the steps if you have already created a new project.

2. Modify Values Folder

Open res/values/strings.xml file. Then, add below code into it.

<resources>
	<string name="app_name">DynamicRadioButtonUsingKotlin</string>
	<string name="male">Male</string>
	<string name="female">Female</string>
	<string name="you_selected">You selected:</string>
</resources>

Other values folder have not been changed. So, we are not going to mention it here.

3. Modify Layout Folder

Open res/layout/activity_main.xml file. Then, add below code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
	android:id="@+id/rootContainer"
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:gravity="center"
	android:orientation="vertical">

	<RadioGroup
		android:id="@+id/radioGroup"
		android:layout_width="match_parent"
		android:layout_height="wrap_content"
		android:paddingStart="20dp">

	</RadioGroup>

</LinearLayout>

In activity_main.xml file, we have added a radio group (having id radioGroup) that will act as container for the radio buttons created dynamically in kotlin file in the project.

4. Create Android Radio Button Programmatically in Kotlin

Open app/src/main/java/com.tutorialwing.dynamicradiobutton/MainActivity.kt file. Then, add below code into it.

package com.tutorialwing.dynamicradiobutton

import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.view.ViewGroup
import android.widget.LinearLayout
import android.widget.RadioButton
import android.widget.RadioGroup
import android.widget.Toast

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val linearLayout = findViewById<LinearLayout>(R.id.rootContainer)

        // Create RadioButton Dynamically
        val radioButton1 = RadioButton(this)
        radioButton1.layoutParams = LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
        radioButton1.setText(R.string.male)
        radioButton1.id = 0

        val radioButton2 = RadioButton(this)
        radioButton2.layoutParams = LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)
        radioButton2.setText(R.string.female)
        radioButton2.id = 1

        val radioGroup = findViewById<RadioGroup>(R.id.radioGroup)
        if (radioGroup != null) {
            radioGroup.addView(radioButton1)
            radioGroup.addView(radioButton2)

            radioGroup.setOnCheckedChangeListener { group, checkedId ->
                var text = getString(R.string.you_selected)
                text += " " + getString(if (checkedId == 0) R.string.male else R.string.female)
                Toast.makeText(applicationContext, text, Toast.LENGTH_SHORT).show()
            }
        }
    }
}

In this file, we have created two radio buttons dynamically. Then, we have added these radio buttons in radio group. After that, we have added a listener in radio group to show toast message whenever radio buttons selection change in radio group.

Since AndroidManifest.xml file is very important in any android application, we are going to see the content inside this file.

AndroidManifest.xml file

Code inside src/main/AndroidManifest.xml file is –

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

	<application
		android:allowBackup="true"
		android:icon="@mipmap/ic_launcher"
		android:label="@string/app_name"
		android:roundIcon="@mipmap/ic_launcher_round"
		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>

When we run the application, we will get output as shown above.

That’s end of tutorial on Creating Android Radio Button programmatically in kotlin.