一、界面设计：
1、activity_main.xml文件：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
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=".MainActivity" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" > <TextView
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="@string/name" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/age" />
</LinearLayout> <ListView
android:id="@+id/listView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="20dp" > </ListView> </RelativeLayout>
2、item.xml文件：用于显示每一行的内容
<?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="horizontal" > <TextView
android:id="@+id/name"
android:layout_width="120dp"
android:layout_height="wrap_content"
/>
<TextView
android:id="@+id/age"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
3、最终测试界面：
每行显示用户名称和年龄。
二、三种方式将数据绑定到ListView控件上：
package com.example.listview; import java.util.ArrayList;
import java.util.HashMap;
import java.util.List; import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.widget.SimpleCursorAdapter;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast; import com.example.entity.Person;
import com.example.lservice.DBPersonService;
import com.example.lservice.PersonAdapter; public class MainActivity extends Activity { private ListView listView;
private DBPersonService personService; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) this.findViewById(R.id.listView);
personService = new DBPersonService(this);
//监听行点击事件
listView.setOnItemClickListener(new OnItemClickListener() {
//parent:指当前被点击条目的listview view：指当前被点击的条目 position:被点击条目的索引
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
ListView lv = (ListView) parent;
/*
* 1、自定义适配器当前条目是Person对象。
* 2、采用SimpleCursorAdapter适配器，返回的是Cursor对象。
* 3、采用SimpleAdapter适配器，返回的是HashMap<String, Object>对象。
*/
Person p = (Person) lv.getItemAtPosition(position);
String info = p.getName() + " " + position + " " + id;
Toast.makeText(getApplicationContext(), info, 1).show(); } });
show3();
} //第一种： 使用SimpleAdapter作为适配器
private void show() {
List<Person> persons = personService.getScrollData(0, 20);
List<HashMap<String, Object>> data = new ArrayList<HashMap<String, Object>>();
for (Person person : persons) {
HashMap<String, Object> map = new HashMap<String, Object>();
map.put("name", person.getName());
map.put("age", person.getAge());
data.add(map);
}
SimpleAdapter adapter = new SimpleAdapter(this, data,
R.layout.item,// 就是一个界面显示文件item.xml
new String[] { "name", "age" },//from： 从结果集中获取数据，将需要显示的数据列名放到该集合
new int[] { R.id.name, R.id.age }// to:将结果集的数据字段对应到listview（item.xml）上
);
listView.setAdapter(adapter);
} //第二种： 使用SimpleCursorAdapter作为适配器
private void show2() {
Cursor cursor = personService.getCursorScrollData(0, 20);
// 使用SimpleCursorAdapter适配器注意两个问题：
// 1、返回的游标对象不能被关闭。
// 2、查询语句字段必须有"_id"这个字段，例如：select id as _id,name,age from person。
@SuppressWarnings("deprecation")
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,
R.layout.item, cursor, new String[] { "name", "age" },
new int[] { R.id.name, R.id.age });
listView.setAdapter(adapter);
} //第三种： 自定义适配器PersonAdapter
private void show3() {
List<Person> persons = personService.getScrollData(0, 10);
PersonAdapter adapter = new PersonAdapter(this, persons, R.layout.item);
listView.setAdapter(adapter);
} @Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
} }
自定义适配器类实现：
package com.example.lservice; import java.util.List; import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView; import com.example.entity.Person;
import com.example.listview.R; public class PersonAdapter extends BaseAdapter {
//被绑定的数据
private List<Person> persons;
//绑定条目界面
private int resource;
//布局填充，作用是可以用xml文件生成View对象
private LayoutInflater inflater; public PersonAdapter(Context context,List<Person> persons, int resource) {
this.persons = persons;
this.resource = resource;
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
} @Override
public int getCount() {
return persons.size();
} @Override
public Object getItem(int position) {
return persons.get(position);
} @Override
public long getItemId(int position) {
return position;
} //会缓存之前的View
@Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView nameView =null;
TextView ageView = null;
if (convertView == null) {// 表示是第一页，需要创建该对象
//生成条目界面对象
convertView = inflater.inflate(resource, null);
nameView = (TextView) convertView.findViewById(R.id.name);
ageView = (TextView) convertView.findViewById(R.id.age);
ViewCache cache = new ViewCache();
cache.ageView=ageView;
cache.nameView=nameView;
//Tags can also be used to store data within a view without resorting to another data structure.
convertView.setTag(cache);
}else{
ViewCache cache = (ViewCache) convertView.getTag();
nameView = cache.nameView;
ageView = cache.ageView;
}
// TextView nameView = (TextView) convertView.findViewById(R.id.name);
// TextView ageView = (TextView) convertView.findViewById(R.id.age);
Person person = persons.get(position);
nameView.setText(person.getName());
//setText方法：被设置的值要转换成字符串类型，否则出错
ageView.setText(person.getAge().toString()); return convertView;
}
/**
* 由于每次都要查找View对象，因此就通过setTag将其保存起来。
* @author Administrator
*
*/
private final class ViewCache{
public TextView nameView;
public TextView ageView; }
}