一. listveiw是android中最常用的布局组件之一，继承自viewgroup。他和gridview是组成android的最常用的组件。
二. adapter分为4个可用的组件，有arrayAdapter,simpleAdapter,baseadapter，和数据库游标adapter，这里主要介绍baseadapter
三.
四. 代码示例：
1.在加载时查找到listview
2.new 一个adapter
3.给listview设置adapter为这个刚刚new出来的adapter
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在第二步new一个adapter时，需要做以下几点
1.class一个新类，继承自baseadapter
2.因为baseadapter是接口，需要重写4个方法。
3.最关键的是重写getview方法，
a）如果convertview为空时，view.inflate解析一个资源文件中视图。
b）解析一行数据，用javabean，取得当前行位置的数据。
ShopInfo shopInfo = data.get(position);
c）得到子view对象。
ImageView imageView = (ImageView) convertView.findViewById(R.id.iv_item_icon);
TextView nameTV = (TextView) convertView.findViewById(R.id.tv_item_name);
TextView contentTV = (TextView) convertView.findViewById(R.id.tv_item_content);
d) 为子view对象，设置数据。
imageView.setImageResource(shopInfo.getIcon());
nameTV.setText(shopInfo.getName());
contentTV.setText(shopInfo.getContent());
e）返回convertview
return convertView;
package com.atguigu.l03_listview; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.os.Bundle; import android.util.Log; import android.view.TextureView; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.ListView; import android.widget.TextView; public class MainActivity extends Activity { private ListView lv_main; private List<ShopInfo> data; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); lv_main = (ListView) findViewById(R.id.lv_main); //准备集合数据 data = new ArrayList<ShopInfo>(); data.add(new ShopInfo(R.drawable.f1, "name----1", "content----1")); data.add(new ShopInfo(R.drawable.f2, "name----2", "content----2")); data.add(new ShopInfo(R.drawable.f3, "name----3", "content----3")); data.add(new ShopInfo(R.drawable.f4, "name----4", "content----4")); data.add(new ShopInfo(R.drawable.f5, "name----5", "content----5")); data.add(new ShopInfo(R.drawable.f6, "name----6", "content----6")); data.add(new ShopInfo(R.drawable.f7, "name----7", "content----7")); data.add(new ShopInfo(R.drawable.f8, "name----8", "content----8")); data.add(new ShopInfo(R.drawable.f9, "name----9", "content----9")); data.add(new ShopInfo(R.drawable.f10, "name----10", "content----10")); //准备BaseAdapter对象 MyAdapter adapter = new MyAdapter(); //设置Adapter显示列表 lv_main.setAdapter(adapter); } class MyAdapter extends BaseAdapter { //返回集合数据的数量 @Override public int getCount() { Log.e("TAG", "getCount()"); return data.size(); } //返回指定下标对应的数据对象 @Override public Object getItem(int position) { return data.get(position); } @Override public long getItemId(int position) { return 0; } /** * 返回指定下标所对应的item的View对象 * position : 下标 * convertView : 可复用的缓存Item视图对象, 前n+1个为null * parent : ListView对象 */ @Override public View getView(int position, View convertView, ViewGroup parent) { //Log.e("TAG", "getView() position="+position+" convertView="+convertView); //如果没有复用的 if(convertView==null) { Log.e("TAG", "getView() position="+position+" convertView="+convertView); //加载item的布局, 得到View对象 convertView = View.inflate(MainActivity.this, R.layout.item_simple_adapter, null); } //根据position设置对应的数据 //得到当前行的数据对象 ShopInfo shopInfo = data.get(position); //得到子View对象 ImageView imageView = (ImageView) convertView.findViewById(R.id.iv_item_icon); TextView nameTV = (TextView) convertView.findViewById(R.id.tv_item_name); TextView contentTV = (TextView) convertView.findViewById(R.id.tv_item_content); //设置数据 imageView.setImageResource(shopInfo.getIcon()); nameTV.setText(shopInfo.getName()); contentTV.setText(shopInfo.getContent()); return convertView; } } }
bean：
package com.atguigu.l03_listview; /** * 每行Item的数据信息封装类 * @author 张晓飞 * */ public class ShopInfo { private int icon; private String name; private String content; public ShopInfo(int icon, String name, String content) { super(); this.icon = icon; this.name = name; this.content = content; } public ShopInfo() { super(); } public int getIcon() { return icon; } public void setIcon(int icon) { this.icon = icon; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } @Override public String toString() { return "ShopInfo [icon=" + icon + ", name=" + name + ", content=" + content + "]"; } }
布局文件：item_simple_adapter
<?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="wrap_content" android:orientation="horizontal" > <ImageView android:id="@+id/iv_item_icon" android:layout_width="70dp" android:layout_height="70dp" android:src="@drawable/f1" /> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:gravity="center_vertical" android:layout_marginLeft="10dp"> <TextView android:id="@+id/tv_item_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="TextView" /> <TextView android:id="@+id/tv_item_content" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="TextView" /> </LinearLayout> </LinearLayout>