How to use android RadioGroup

Create a main class
for MainActivity.java

 
<?xml version="1.0" encoding="UTF-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:layout_width="fill_parent" 
android:layout_height="fill_parent" 
android:orientation="vertical"> 
<TextView 
android:id="@+id/radiobutton_textview" 
android:layout_width="fill_parent" 
android:layout_height="50dip" 
android:textSize="18dip" 
android:textStyle="bold" 
android:background="@android:drawable/title_bar" 
android:textAppearance="?android:attr/textAppearanceLarge" 
android:gravity="center_vertical" 
/> 
<RadioGroup 
android:id="@+id/group" 
android:layout_width="fill_parent" 
android:layout_height="wrap_content" 
android:orientation="vertical"> 
<RadioButton 
android:id="@+id/button1" 
android:layout_width="fill_parent" 
android:layout_height="50dip" 
android:textSize="20dip" 
android:paddingLeft="30dip" 
android:text="Android A novice " 
android:button="@null" 
android:drawableRight="@android:drawable/btn_radio"/> 
<View 
android:layout_width="fill_parent" 
android:layout_height="1px" 
android:background="?android:attr/listDivider" 
/> 
<RadioButton 
android:id="@+id/button2" 
android:layout_width="fill_parent" 
android:layout_height="50dip" 
android:textSize="20dip" 
android:paddingLeft="30dip" 
android:text="Android master " 
android:button="@null" 
android:drawableRight="@android:drawable/btn_radio"/> 
</RadioGroup> 
</LinearLayout> 

Xml code

 
package endual.radio; 
import android.app.Activity; 
import android.os.Bundle; 
import android.widget.RadioButton; 
import android.widget.RadioGroup; 
import android.widget.RadioGroup.OnCheckedChangeListener; 
import android.widget.TextView; 
public class MainActivity extends Activity { 
private TextView textView; 
private RadioGroup group; 
private RadioButton rb1 ; 
private RadioButton rb2 ; 
/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.main); 
textView = (TextView) findViewById(R.id.radiobutton_textview); 
group = (RadioGroup) findViewById(R.id.group); 
this.rb1 = (RadioButton) this.findViewById(R.id.button1) ; 
this.rb2 = (RadioButton) this.findViewById(R.id.button2) ; 

//  The radio button group listens for events  
group.setOnCheckedChangeListener(new OnCheckedChangeListener() { 
@Override 
public void onCheckedChanged(RadioGroup group, int checkedId) { 
//  According to the ID Determine the selected button  
if (checkedId == R.id.button1) { 

textView.setText("Android A novice "); 
rb1.setText(" I am a 1") ; 
String msg = rb1.getText().toString() ; // Get individual radioButton The button  
rb2.setText(msg) ; 
//System.out.println(); 
} else { 
textView.setText("Android master "); 
rb2.setText(" I am a 2") ; 
} 
} 
}); 
} 
} 

RadioGroup registers the listener event OnCheckedChangeListener(), which implements the business logic in onCheckedChanged.