package kr.co.naver;

import java.security.PublicKey;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.util.AttributeSet;
import android.view.View;

import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.RadioButton;

public class Widget3Activity extends Activity {
   
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
       
        Radio1 radioB1 = (Radio1)findViewById(R.id.radiobtn1);
        Radio1 radioB2 = (Radio1)findViewById(R.id.radiobtn2);
        Radio1 radioB3 = (Radio1)findViewById(R.id.radiobtn3);
        Radio1 radioB4 = (Radio1)findViewById(R.id.radiobtn4);
       
        TextView text = (TextView)findViewById(R.id.answer);
        text.setText(radioB1.Ans1);
        text.setText(radioB2.Ans2);
        text.setText(radioB3.Ans3);
        text.setText(radioB4.Ans4);
      
    }
}
class Radio1 extends RadioButton{
 String Ans1="";
 String Ans2="";
 String Ans3="";
 String Ans4="";
 
 RadioGroup Group = (RadioGroup)findViewById(R.id.Group);
 Group.setOnCheckedChangeListener(mRadioCheck);

 public Radio1(Context context, AttributeSet attrs, int defStyle) {
  super(context, attrs, defStyle);
 }
 public Radio1(Context context, AttributeSet attrs){
  super(context, attrs);
 }
 public Radio1(Context context){
  super(context);
 }
 
 
 RadioGroup.OnCheckedChangeListener mRadioCheck = new RadioGroup.OnCheckedChangeListener() {
  
  public void onCheckedChanged(RadioGroup group, int checkedId) {
   
   if(group.getId() = R.id.Group){
    switch (checkedId) {
    case R.id.radiobtn1:
     Ans1.setText("A형");
     break;
    case R.id.radiobtn2:
     Ans2.setText("B형");
     break;
    case R.id.radiobtn3:
     Ans3.setText("O형");
     break;
    case R.id.radiobtn4:
     Ans4.setText("AB형");
     break;
    }
   }
   
  }
 }; 
}

////////////////////////////////////////////////////////////////////////////////////

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical" android:layout_width="fill_parent"
 android:layout_height="fill_parent">
 <TextView
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:text="당신의 혈액형이 무엇입니까?"/>
 
 <RadioGroup
     android:id="@+id/Group"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:orientation="horizontal">
 <kr.co.naver.Radio1
     android:id="@+id/radiobtn1"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="A형" />
 <kr.co.naver.Radio2
     android:id="@+id/radiobtn2"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="B형" />
 <kr.co.naver.Radio3
     android:id="@+id/radiobtn3"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="O형" />
 <kr.co.naver.Radio4
     android:id="@+id/radiobtn4"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="AB형" />
 </RadioGroup>
 
 <TextView
     android:id="@+id/answer"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:textSize="10sp"/>
</LinearLayout>

여기서 클래스를 분리시켜서 하려고 했는데 이름모를 에러만 납니다

해결좀 해주세요...