Radio buttons allow the user to select one option at a time. A RadioButton
as two states, selected and unselected.
Create a new Project in Kotlin
- Open Android Studio.
- Go to File => New => New Project. Write application name . Then, check Include Kotlin Support and click next button.
- Select minimum SDK you need. However, we have selected 17 as minimum SDK. Then, click next button
- Then, select Empty Activity => click next => click finish.
- You will get a newly created project successfully if you have followed steps properly.
Use the below code to Implement a Radio Buttons with Kotlin
MainActivity.kt
activity_main.xml
import android.support.v7.app.AppCompatActivity import android.os.Bundle import android.view.View import android.widget.* import kotlinx.android.synthetic.main.activity_main.* import android.widget.RadioGroup import android.widget.Toast class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) //Radio button on click change radio_group.setOnCheckedChangeListener( RadioGroup.OnCheckedChangeListener{ group, checkedId -> val radio_langange: RadioButton = findViewById(checkedId) Toast.makeText(applicationContext," On Checked change :${radio_langange.text}",Toast.LENGTH_SHORT).show() } ) // Get radio group selected status and text using button click event button.setOnClickListener{ // Get the checked radio button id from radio group var id: Int = radio_group.checkedRadioButtonId if (id!=-1){ // If any radio button checked from radio group // Get the instance of radio button using id val radio:RadioButton = findViewById(id) Toast.makeText(applicationContext,"On button click : ${radio.text}", Toast.LENGTH_SHORT).show() }else{ // If no radio button checked in this radio group Toast.makeText(applicationContext,"On button click : nothing selected", Toast.LENGTH_SHORT).show() } } } // Get the selected radio button text using radio button on click listener fun radio_button_click(view: View){ // Get the clicked radio button instance val radio: RadioButton = findViewById(radio_group.checkedRadioButtonId) Toast.makeText(applicationContext,"On click : ${radio.text}", Toast.LENGTH_SHORT).show() } }
activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/root_layout" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:padding="16dp" > <RadioGroup android:layout_marginTop="30dp" android:id="@+id/radio_group" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="#bccdd5" android:padding="15dp" > <TextView android:id="@+id/title" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Which is your favorite languages?" android:textStyle="bold" android:textSize="20sp" /> <RadioButton android:id="@+id/tvenglish" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="English" android:onClick="radio_button_click" /> <RadioButton android:id="@+id/tvspanish" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Spanish" android:onClick="radio_button_click" /> <RadioButton android:id="@+id/tvfrench" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="French" android:onClick="radio_button_click" /> <RadioButton android:id="@+id/tvmalayalam" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Malayalam" android:onClick="radio_button_click" /> </RadioGroup> <Button android:id="@+id/button" android:layout_gravity="center" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="15dp" android:text="Get Selected Language" /> </LinearLayout>
