은성이의 프로그램X파일

 package org.kosta.radiobtn.test;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
import android.support.v4.app.NavUtils;

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button btn = (Button) findViewById(R.id.btn);
        btn.setOnClickListener(new OnClickListener(){
         public void onClick(View v){
          RadioGroup ageRG = (RadioGroup)findViewById(R.id.age_rg);
          //RadioGroup내에 선택된 RadioButton의 ID를 조회
          int id = ageRG.getCheckedRadioButtonId();//선택된 것의 ID를 리턴해줌(R.java에 있는 0x1111과 같은 값을 리턴해줌)
          RadioButton rd = (RadioButton) findViewById(id);//text로 ID를 리턴하도록 변환
          String txt = (String)rd.getText();//rd값을 얻어옴
          Toast.makeText(MainActivity.this, txt, Toast.LENGTH_SHORT).show();//화면에 짧은 시간 txt 값을 보여줌
         }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

   
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
   
    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="나이를 선택하세요"/>
    <RadioGroup
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:id="@+id/age_rg">
        <RadioButton
            android:layout_width="match_parent"
         android:layout_height="wrap_content"
            android:text="10대"
            android:id="@+id/age1"/>
        <RadioButton
            android:layout_width="match_parent"
         android:layout_height="wrap_content"
            android:text="20대"
            android:id="@+id/age2"/>
        <RadioButton
            android:layout_width="match_parent"
         android:layout_height="wrap_content"
            android:text="30대"
            android:id="@+id/age3"/>
        <RadioButton
            android:layout_width="match_parent"
         android:layout_height="wrap_content"
            android:text="40대"
            android:id="@+id/age4"/>
    </RadioGroup>
 <Button
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:text="선택 나이 조회"
     android:id="@+id/btn"/>
</LinearLayout>