Android控件之CheckBox

package com.example.textview;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.CheckBox;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
public class MainActivity extends Activity {

private CheckBox Box1=null;
private CheckBox Box2=null;
private CheckBox Box3=null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Box1=(CheckBox)findViewById(R.id.checkBox1);
Box2=(CheckBox)findViewById(R.id.checkBox2);
Box3=(CheckBox)findViewById(R.id.checkBox3);
Box1.setOnClickListener(listener);
Box2.setOnClickListener(listener);
Box3.setOnClickListener(listener);

}
private OnClickListener listener=new OnClickListener() {

@Override
public void onClick(View v) {

if(Box1.isChecked())
{
System.out.println("Box1");
}
if(Box2.isChecked())
{
System.out.println("Box2");
}
if(Box3.isChecked())
{
System.out.println("Box3");
}

}
};

}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="${relativePackage}.${activityClass}" >

<CheckBox
android:id="@+id/checkBox1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginTop="40dp"
android:text="CheckBox" />

<CheckBox
android:id="@+id/checkBox2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/checkBox1"
android:text="CheckBox" />

<CheckBox
android:id="@+id/checkBox3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/checkBox2"
android:text="CheckBox" />

</RelativeLayout>