Android实战简易教程-第四十七枪（ListView多选-实现点餐系统）

一般在外卖的选单中常常会用到ListView的多选，大家可以改进后加入自己的项目中。下面看一下代码：

一、代码

1.main.xml:（由一个ListView和一个Button组成）

 <span style="font-size:14px;">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" >

     <ListView
         android:id="@+id/drink_list"
         android:layout_width="fill_parent"
         android:layout_height="0dp"
         android:layout_weight="1" >
     ListView>

     <Button
         android:id="@+id/btn_commit"
         android:layout_width="match_parent"
         android:layout_height="58dp"
         android:text="确定" />

 LinearLayout>span>

2.item.xml:

 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:background="#ffffff"
     android:orientation="horizontal" >

     <CheckBox
         android:id="@+id/check_box"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:clickable="false"
         android:focusable="false"
         android:focusableInTouchMode="true" />

     <ImageView
         android:id="@+id/food_imager"
         android:layout_width="50dp"
         android:layout_height="50dp"
         android:background="#ffffff" />

     <TextView
         android:id="@+id/food_name"
         android:layout_width="100dp"
         android:layout_height="50dp"
         android:text="咖啡"
         android:gravity="center_vertical"
         android:layout_marginLeft="10dp"
         android:textSize="18sp" />

     <TextView
         android:layout_width="wrap_content"
         android:layout_height="50dp"
         android:text="单价：RMB  "
         android:paddingLeft="20dp"
         android:textSize="12sp" />

     <TextView
         android:id="@+id/price"
         android:layout_width="wrap_content"
         android:layout_height="50dp"
         android:paddingRight="10dp"
         android:text="18"
         android:layout_marginLeft="20dp"
         android:textSize="18sp" />

 LinearLayout>

3.Food.java:(bean类)

 package com.example.info;

 public class Food {

     public int food_img;
     public String food_name;
     public String food_price;
     public String text;

     public int getFood_img() {
         return food_img;
     }

     public void setFood_img(int food_img) {
         this.food_img = food_img;
     }

     public String getFood_name() {
         return food_name;
     }

     public void setFood_name(String food_name) {
         this.food_name = food_name;
     }

     public String getFood_price() {
         return food_price;
     }

     public void setFood_price(String food_price) {
         this.food_price = food_price;
     }

     public Food(int food_img, String food_name, String food_price) {
         super();
         this.food_img = food_img;
         this.food_name = food_name;
         this.food_price = food_price;
     }

     public Food() {
         super();
     }

     @Override
     public String toString() {
         return super.toString();
     }
 }

4.MyListViewAdapter.java:

 package com.example.adapter;

 import java.util.ArrayList;
 import java.util.HashMap;

 import com.example.info.Food;
 import com.example.listviewselectitem.R;

 import android.content.Context;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 import android.widget.CheckBox;
 import android.widget.ImageView;
 import android.widget.TextView;

 public class MyListViewAdapter extends BaseAdapter {
     // 填充数据的list
     private ArrayList foodlist;
     // 用来控制CheckBox的选中状况
     private static HashMap isSelected;
     // 上下文
     private Context context;
     // 用来导入布局
     private LayoutInflater inflater = null;

     // 构造器
     public MyListViewAdapter(ArrayList list, Context context) {
         this.context = context;
         this.foodlist = list;
         inflater = LayoutInflater.from(context);
         isSelected = new HashMap();
         // 初始化数据
         initDate();
     }

     // 初始化isSelected的数据
     private void initDate() {
         for (int i = 0; i < foodlist.size(); i++) {
             getIsSelected().put(i, false);
         }
     }

     @Override
     public int getCount() {
         return foodlist.size();
     }

     @Override
     public Object getItem(int position) {
         return foodlist.get(position);
     }

     @Override
     public long getItemId(int position) {
         return position;
     }

     @Override
     public View getView(int position, View convertView, ViewGroup parent) {
         ViewHolder holder = null;
         if (convertView == null) {
             // 获得ViewHolder对象
             holder = new ViewHolder();
             // 导入布局并赋值给convertview
             convertView = inflater.inflate(R.layout.item, null);
             holder.imageView = (ImageView) convertView
                     .findViewById(R.id.food_imager);
             holder.txt1 = (TextView) convertView.findViewById(R.id.food_name);
             holder.txt2 = (TextView) convertView.findViewById(R.id.price);
             holder.cb = (CheckBox) convertView.findViewById(R.id.check_box);
             // 为view设置标签
             convertView.setTag(holder);
         } else {
             // 取出holder
             holder = (ViewHolder) convertView.getTag();
         }
         // 获取数据
         Food food = foodlist.get(position);

         // 将数据填充到当前convertView的对应控件中

         holder.imageView.setImageResource(food.food_img);
         holder.txt1.setText(food.food_name);
         holder.txt2.setText(food.food_price);
         // 设置list中TextView的显示
         // 根据isSelected来设置checkbox的选中状况
         holder.cb.setChecked(getIsSelected().get(position));
         return convertView;
     }

     public static HashMap getIsSelected() {
         return isSelected;
     }

     public static void setIsSelected(HashMap isSelected) {
         MyListViewAdapter.isSelected = isSelected;
     }

     public static class ViewHolder {
         public TextView txt1;
         public TextView txt2;
         public ImageView imageView;
         public CheckBox cb;
     }
 }

5.MainActivity.java:

 package com.example.listviewselectitem;

 import java.util.ArrayList;
 import java.util.HashMap;

 import com.example.adapter.MyListViewAdapter;
 import com.example.adapter.MyListViewAdapter.ViewHolder;
 import com.example.info.Food;

 import android.os.Bundle;
 import android.app.Activity;
 import android.content.Context;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.Window;
 import android.view.View.OnClickListener;
 import android.widget.AdapterView;
 import android.widget.Button;
 import android.widget.CheckBox;
 import android.widget.ListView;
 import android.widget.Toast;
 import android.widget.AdapterView.OnItemClickListener;

 public class MainActivity extends Activity implements OnClickListener,
         OnItemClickListener {

     private ListView listView;
     private Button ok;
     private ArrayList foods = new ArrayList();
     private MyListViewAdapter adapter;
     private CheckBox checkBox;

     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         requestWindowFeature(Window.FEATURE_NO_TITLE);
         setContentView(R.layout.activity_main);
         initView();// 初始化控件
         View view=LayoutInflater.from(this).inflate(R.layout.item, null);
         checkBox=(CheckBox)view.findViewById(R.id.check_box);

         initData();// 初始化虚拟数据

         adapter = new MyListViewAdapter(foods, getApplicationContext());
         listView.setAdapter(adapter);
     }

     /**
      * 初始化控件
      * */
     public void initView() {
         listView = (ListView) findViewById(R.id.drink_list);// listview列表控件
         ok = (Button) findViewById(R.id.btn_commit);// 确定按钮

         ok.setOnClickListener(this);
         listView.setOnItemClickListener(this);
     }

     /**
      * 初始化虚拟数据
      * */
     public void initData() {




         Class cls = R.drawable.class;//反射
         try {
             foods.add(new Food(cls.getDeclaredField("d1").getInt(null), "猕猴桃汁",
                     "10"));
             foods.add(new Food(cls.getDeclaredField("d2").getInt(null), "橙汁",
                     "12"));
             foods.add(new Food(cls.getDeclaredField("d3").getInt(null), "啤酒",
                     "15"));
             foods.add(new Food(cls.getDeclaredField("d4").getInt(null), "葡萄汁",
                     "10"));
             foods.add(new Food(cls.getDeclaredField("d5").getInt(null), "纯麦奶茶",
                     "8"));
             foods.add(new Food(cls.getDeclaredField("d6").getInt(null), "薄荷汁",
                     "10"));
             foods.add(new Food(cls.getDeclaredField("d7").getInt(null), "柠檬薄荷",
                     "12"));
             foods.add(new Food(cls.getDeclaredField("d8").getInt(null), "椰子汁",
                     "10"));
             foods.add(new Food(cls.getDeclaredField("d9").getInt(null), "珍珠奶茶",
                     "9"));
             foods.add(new Food(cls.getDeclaredField("d10").getInt(null), "石榴汁",
                     "10"));

         } catch (Exception e) {
             e.printStackTrace();
         }
     }

     /**
      * 按钮的点击事件处理
      * */
     @Override
     public void onClick(View v) {
         int mID = v.getId();
         switch (mID) {
         case R.id.btn_commit:
             myPrice();// 计算总价并输出
             break;

         }
     }

     /**
      * 计算总价格的方法
      * */
     public void myPrice() {
         HashMap map = MyListViewAdapter.getIsSelected();
         String str = "";
         int money = 0;
         for (int i = 0; i < map.size(); i++) {
             if (map.get(i)) {
                 str += (i + " ");
                 money += Integer.parseInt(foods.get(i).food_price);
             }
         }
         MyListViewAdapter.getIsSelected().get("");
         Toast.makeText(getApplicationContext(),
                 "已选中了" + str + "项,总价钱为:" + money, Toast.LENGTH_SHORT).show();
     }

     /**
      * listview的item的选择的方法
      * */
     @Override
     public void onItemClick(AdapterView parent, View view, int position,
             long id) {
         // 取得ViewHolder对象，这样就省去了通过层层的findViewById去实例化我们需要的cb实例的步骤
         ViewHolder holder = (ViewHolder) view.getTag();
         // 改变CheckBox的状态
         holder.cb.toggle();
         // 将CheckBox的选中状况记录下来
         MyListViewAdapter.getIsSelected().put(position, holder.cb.isChecked());

     }
 }

二、运行实例

来源：http://blog.csdn.net/chenyanpeng2003