Android-20-CheckBox复选框

MainActivity.java:

import android.app.Activity;import android.os.Bundle;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.CheckBox;import android.widget.Toast;public class MainActivity extends Activity implements OnClickListener {	private CheckBox basketball,football,baseball,pingpang;	private Button button;		@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.activity_main);		basketball = (CheckBox) findViewById(R.id.basketball);		baseball = (CheckBox) findViewById(R.id.baseball);		football = (CheckBox) findViewById(R.id.football);		pingpang = (CheckBox) findViewById(R.id.pingpang);		button = (Button) findViewById(R.id.button);		button.setOnClickListener(this);	}	@Override	public void onClick(View v) {		// TODO Auto-generated method stub		String s = "";		boolean flag = false;		if (basketball.isChecked()){			s += basketball.getText().toString();			flag = true;		}		if (baseball.isChecked()){			s += baseball.getText().toString();			flag = true;		}		if (football.isChecked()){			s += football.getText().toString();			flag = true;		}		if (pingpang.isChecked()){			s += pingpang.getText().toString();			flag = true;		}		if (flag == false){			Toast.makeText(MainActivity.this, "没有任何选项", 0).show();		}else {			Toast.makeText(MainActivity.this, s, 0).show();		}	}}

activity_main.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="vertical"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.checkboxdemo2.MainActivity" >    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="选择爱好" />    <LinearLayout        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:orientation="vertical" >        <CheckBox            android:id="@+id/basketball"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:text="篮球" />        <CheckBox            android:id="@+id/football"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:text="足球" />        <CheckBox            android:id="@+id/baseball"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:text="网球" />        <CheckBox            android:id="@+id/pingpang"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:text="乒乓球" />    </LinearLayout>    <Button        android:id="@+id/button"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="确定" /></LinearLayout>