代码改变世界

Android之自定义Adapter的ListView

2013-12-03 19:36  @疯狂的迈步  阅读(187)  评论(0编辑  收藏  举报

ListView的创建,一般要具备两大元素:

1)数据集,即要映射的字符串、图片信息之类。

2)适配器,实现把要映射的字符串、图片信息映射成视图(如Textview、Image等组件),再添加到ListView中。

下面是一个实操例子:

实现细节:

1、创建数据集,一般定义如下

private List<Map<String, Object>> listItems;

元素添加方式:

Map<String, Object> map = new HashMap<String, Object>(); 
        map.put("image", imgeIDs[i]);          //图片资源
        map.put("title", "物品名称:");           //物品标题
        map.put("info", goodsNames[i]);      //物品名称
        map.put("detail", goodsDetails[i]);   //物品详情
        listItems.add(map);                         //添加一项

2、创建适配器

public class ListViewAdapter extends BaseAdapter{........}  //自定义的适配器一般继承BaseAdapter类

        listViewAdapter = new ListViewAdapter(this, listItems);

3、给ListView设置适配器

listView.setAdapter(listViewAdapter);

4、这里还有个关键点,如何把list_item.xml布局作为一个视图,添加到listView中:

        LayoutInflater listContainer;   //视图容器工厂

        listContainer = LayoutInflater.from(context); //创建视图容器工厂并设置上下文

        convertView = listContainer.inflate(R.layout.list_item, null);   //创建list_item.xml布局文件的视图

 

----------------------------------亲测有用-------------------------------

1)布局文件main.xml

<?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">
<!-- 结算 -->
<LinearLayout Android:gravity="center_horizontal"
Android:orientation="horizontal" android:layout_width="fill_parent"
Android:layout_height="wrap_content">
<TextView Android:text="结算: "
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:textColor="#FFFFFFFF"
Android:textSize="20px"/>
<ImageButton Android:id="@+id/imgbt_sum"
Android:layout_width="40px"
Android:layout_height="40px"
Android:background = "@drawable/shopping" />
</LinearLayout>
<TextView Android:text="商品列表: "
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:textColor="#FFFFFFFF" />
<!-- 商品列表 -->
<ListView Android:id="@+id/list_goods"
Android:layout_width="fill_parent"
Android:layout_height="wrap_content" />
</LinearLayout>




列表项布局文件list_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:Android="http://schemas.android.com/apk/res/android"
Android:orientation="horizontal" android:layout_width="fill_parent"
Android:layout_height="fill_parent">
<!-- 商品图片 -->
<ImageView Android:id="@+id/imageItem"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:layout_margin="5px"/>
<!-- 商品信息 -->
<LinearLayout Android:orientation="vertical"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content">
<TextView Android:id="@+id/titleItem"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:textColor="#FFFFFFFF"
Android:textSize="13px" />
<TextView Android:id="@+id/infoItem"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:textColor="#FFFFFFFF"
Android:textSize="22px" />
</LinearLayout>
<!-- 购买和商品详情 -->
<LinearLayout Android:gravity="right"
Android:orientation="horizontal" android:layout_width="fill_parent"
Android:layout_height="wrap_content">
<CheckBox Android:id="@+id/checkItem"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:layout_margin="5px"/>
<Button Android:id="@+id/detailItem"
Android:layout_width="wrap_content"
Android:layout_height="wrap_content"
Android:layout_margin="5px"/>
</LinearLayout>
</LinearLayout>

 

 

2)代码,主代码:

package com.myAndroid.test;  
import java.util.ArrayList;  
import java.util.HashMap;  
import java.util.List;  
import java.util.Map;  
import Android.app.Activity;  
import Android.app.AlertDialog;  
import Android.content.DialogInterface;  
import Android.os.Bundle;  
import Android.view.View;  
import Android.view.View.OnClickListener;  
import Android.widget.ArrayAdapter;  
import Android.widget.ImageButton;  
import Android.widget.ListView;  
public class MyListView extends Activity {  
private ListView listView;  
private ImageButton imgbt_sum;  
private ListViewAdapter listViewAdapter;  
private List<Map<String, Object>> listItems;  
private Integer[] imgeIDs = {R.drawable.cake,   
            R.drawable.gift, R.drawable.letter,  
            R.drawable.love, R.drawable.mouse,  
            R.drawable.music};  
private String[] goodsNames = {"蛋糕", "礼物",   
"邮票", "爱心", "鼠标", "音乐CD"};  
private String[] goodsDetails = {  
"蛋糕:好好吃。",   
"礼物:礼轻情重。",   
"邮票:环游世界。",   
"爱心:世界都有爱。",  
"鼠标:反应敏捷。",  
"音乐CD:酷我音乐。"};  
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {  
super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
        listView = (ListView)findViewById(R.id.list_goods);   
        imgbt_sum = (ImageButton) findViewById(R.id.imgbt_sum);  
        imgbt_sum.setOnClickListener(new ClickEvent());  
        listItems = getListItems();  
        listViewAdapter = new ListViewAdapter(this, listItems); //创建适配器
        listView.setAdapter(listViewAdapter);  
    }  
/**
     * 初始化商品信息
     */
private List<Map<String, Object>> getListItems() {  
        List<Map<String, Object>> listItems = new ArrayList<Map<String, Object>>();  
for(int i = 0; i < goodsNames.length; i++) {  
            Map<String, Object> map = new HashMap<String, Object>();   
            map.put("image", imgeIDs[i]);               //图片资源
            map.put("title", "物品名称:");              //物品标题
            map.put("info", goodsNames[i]);     //物品名称
            map.put("detail", goodsDetails[i]); //物品详情
            listItems.add(map);  
        }     
return listItems;  
    }  
class ClickEvent implements OnClickListener{  
@Override
public void onClick(View v) {  
// TODO Auto-generated method stub
            String goodsList = "";  
for(int i = 0; i < listItems.size(); i++) {  
                goodsList += listViewAdapter.hasChecked(i)? goodsNames[i] + "  ": "";  
            }  
new AlertDialog.Builder(MyListView.this)  
            .setTitle("购物清单:")  
            .setMessage("你好,你选择了如下商品:\n" + goodsList)  
            .setPositiveButton("确定", null)  
            .show();  
        }  
    }  
}
 

 

 

适配器代码:

package com.myAndroid.test;  
import java.util.List;  
import java.util.Map;  
import Android.app.AlertDialog;  
import Android.content.Context;  
import Android.util.Log;  
import Android.view.LayoutInflater;  
import Android.view.View;  
import Android.view.ViewGroup;  
import Android.widget.BaseAdapter;  
import Android.widget.Button;  
import Android.widget.CheckBox;  
import Android.widget.CompoundButton;  
import Android.widget.ImageView;  
import Android.widget.ListView;  
import Android.widget.TextView;  
public class ListViewAdapter extends BaseAdapter {  
private Context context;                        //运行上下文
private List<Map<String, Object>> listItems;    //商品信息集合
private LayoutInflater listContainer;           //视图容器
private boolean[] hasChecked;                   //记录商品选中状态
public final class ListItemView{                //自定义控件集合  
public ImageView image;    
public TextView title;    
public TextView info;  
public CheckBox check;  
public Button detail;         
     }    
public ListViewAdapter(Context context, List<Map<String, Object>> listItems) {  
this.context = context;           
        listContainer = LayoutInflater.from(context);   //创建视图容器并设置上下文
this.listItems = listItems;  
        hasChecked = new boolean[getCount()];  
    }  
public int getCount() {  
// TODO Auto-generated method stub
return listItems.size();  
    }  
public Object getItem(int arg0) {  
// TODO Auto-generated method stub
return null;  
    }  
public long getItemId(int arg0) {  
// TODO Auto-generated method stub
return 0;  
    }  
/**
     * 记录勾选了哪个物品
     * @param checkedID 选中的物品序号
     */
private void checkedChange(int checkedID) {  
        hasChecked[checkedID] = !hasChecked[checkedID];  
    }  
/**
     * 判断物品是否选择
     * @param checkedID 物品序号
     * @return 返回是否选中状态
     */
public boolean hasChecked(int checkedID) {  
return hasChecked[checkedID];  
    }  
/**
     * 显示物品详情
     * @param clickID
     */
private void showDetailInfo(int clickID) {  
new AlertDialog.Builder(context)  
        .setTitle("物品详情:" + listItems.get(clickID).get("info"))  
        .setMessage(listItems.get(clickID).get("detail").toString())                
        .setPositiveButton("确定", null)  
        .show();  
    }  
/**
     * ListView Item设置
     */
public View getView(int position, View convertView, ViewGroup parent) {  
// TODO Auto-generated method stub
        Log.e("method", "getView");  
final int selectID = position;  
//自定义视图
        ListItemView  listItemView = null;  
if (convertView == null) {  
            listItemView = new ListItemView();   
//获取list_item布局文件的视图
            convertView = listContainer.inflate(R.layout.list_item, null);  
//获取控件对象
            listItemView.image = (ImageView)convertView.findViewById(R.id.imageItem);  
            listItemView.title = (TextView)convertView.findViewById(R.id.titleItem);  
            listItemView.info = (TextView)convertView.findViewById(R.id.infoItem);  
            listItemView.detail= (Button)convertView.findViewById(R.id.detailItem);  
            listItemView.check = (CheckBox)convertView.findViewById(R.id.checkItem);  
//设置控件集到convertView
            convertView.setTag(listItemView);  
        }else {  
            listItemView = (ListItemView)convertView.getTag();  
        }  
//      Log.e("image", (String) listItems.get(position).get("title"));  //测试
//      Log.e("image", (String) listItems.get(position).get("info"));
//设置文字和图片
        listItemView.image.setBackgroundResource((Integer) listItems.get(  
                position).get("image"));  
        listItemView.title.setText((String) listItems.get(position)  
                .get("title"));  
        listItemView.info.setText((String) listItems.get(position).get("info"));  
        listItemView.detail.setText("商品详情");  
//注册按钮点击时间爱你
        listItemView.detail.setOnClickListener(new View.OnClickListener() {  
@Override
public void onClick(View v) {  
//显示物品详情
                showDetailInfo(selectID);  
            }  
        });  
// 注册多选框状态事件处理
        listItemView.check  
                .setOnCheckedChangeListener(new CheckBox.OnCheckedChangeListener() {  
@Override
public void onCheckedChanged(CompoundButton buttonView,  
boolean isChecked) {  
//记录物品选中状态
                        checkedChange(selectID);  
                    }  
        });  
return convertView;  
    }  
}

 

 

原文链接:http://www.linuxidc.com/Linux/2011-05/35394.htm