安卓app_sl3_15复选框按钮示范

package com.example.sl3_15;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
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.CompoundButton;
import android.widget.Toast;
import android.widget.CompoundButton.OnCheckedChangeListener;




public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final CheckBox like1=(CheckBox)findViewById(R.id.checkBox1);
        final CheckBox like2=(CheckBox)findViewById(R.id.checkBox2);
        final CheckBox like3=(CheckBox)findViewById(R.id.checkBox3);
        like1.setOnCheckedChangeListener(checkBox_listener);
        like2.setOnCheckedChangeListener(checkBox_listener);
        like3.setOnCheckedChangeListener(checkBox_listener);
        Button button=(Button)findViewById(R.id.button1);
        button.setOnClickListener(new OnClickListener(){

            @Override
            public void onClick(View v) {
                // TODO 自动生成的方法存根
                String like="";
                if(like1.isChecked())
                    like+=like1.getText().toString()+"";
                if(like2.isChecked())
                    like+=like2.getText().toString()+"";
                if(like3.isChecked())
                    like+=like3.getText().toString()+"";
                Toast.makeText(MainActivity.this, like, Toast.LENGTH_SHORT).show();
                
            }
            
        });
        
    }
    private OnCheckedChangeListener checkBox_listener=new OnCheckedChangeListener() {

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            // TODO 自动生成的方法存根
            if(isChecked)
            {
                Log.i("复选框", "选中了："+buttonView.getText().toString());
                String tt="选中了："+buttonView.getText().toString();
                Toast.makeText(MainActivity.this,tt , Toast.LENGTH_SHORT).show();
            }
        }
            

            
        };

    
            
}

    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
   android:orientation="vertical"
    tools:context="com.example.sl3_15.MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="40px"
        android:text="爱好:" />

    <CheckBox
        android:id="@+id/checkBox1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="体育" />

    <CheckBox
        android:id="@+id/checkBox2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="音乐" />

    <CheckBox
        android:id="@+id/checkBox3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="美术" />

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="提交" />