How to set Radio Button checked as default in Android

In this android programming source code example, we are going to set Radio Button checked as default in RadioGroup in Android.

You can copy and adopt this source code example to your android project without reinventing the wheel.

Below is a step by step source code to set Radio Button checked as default in RadioGroup in Android.

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:orientation="vertical" 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=".radiobutton.RadioButton4"
    android:layout_margin="10dp">

    <TextView
        android:id="@+id/textView25"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="RadioButton 2 Checked At Runtime" />

    <RadioButton
        android:id="@+id/radioButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="RadioButton1" />

    <RadioButton
        android:id="@+id/radioButton2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="RadioButton2" />

    <RadioButton
        android:id="@+id/radioButton3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="RadioButton3" />

</LinearLayout>

MainActivity.java

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.RadioButton;

public class RadioButton4 extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_radio_button4);

        RadioButton radioButton = findViewById(R.id.radioButton2);
        radioButton.setChecked(true);
    }
}

If you have any question or suggestions kindly use the comment box or you can contact us directly through our contact page below.

 

Add a Comment