Android之SimpleAdapter

学习Android，整理一下SimpleAdapter的知识，通过一个小例子来看具体代码（下图中的头像小图片请自行添加），

如下图：

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1.0： 在layout文件夹下，新建list_view.xml文件

list_view.xml：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout_list_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ImageView
        android:id="@+id/imageview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true" />
    <TextView
        android:id="@+id/textview01"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="18sp"
        android:layout_toRightOf="@id/imageview" />
    <TextView
        android:id="@+id/textview02"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="12sp"
        android:layout_toRightOf="@id/imageview"
        android:layout_below="@id/textview01" />

</RelativeLayout>

2.0： 在activity_main.xml文件中添加一个ListView控件

activity_main.xml：

<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"
    tools:context="com.lgl.simpleadapter.MainActivity" >

    <ListView
        android:id="@+id/listview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

</RelativeLayout>

3.0： 新建一个Person类

Person：

package com.lgl.simpleadapter;

public class Person {

    private int id;
    private String name;
    private String desc;

    public Person(int id, String name, String desc) {
        super();
        this.id = id;
        this.name = name;
        this.desc = desc;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDesc() {
        return desc;
    }
    public void setDesc(String desc) {
        this.desc = desc;
    }

}

4.0： 在MainActivity中做代码实现

MainActivity：

package com.lgl.simpleadapter;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.Activity;
import android.os.Bundle;
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;

public class MainActivity extends Activity {

    private ListView listView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //获取控件
        listView = (ListView) findViewById(R.id.listview);
        //创建数据源
        Person person1 = new Person(R.drawable.f1, "JAVA", "小菜一碟！");
        Person person2 = new Person(R.drawable.f2, "Android", "有点意思！");
        Person person3 = new Person(R.drawable.f3, "SSH", "不在话下！");
        Person person4 = new Person(R.drawable.f4, "JAVA EE", "手到擒来！");
        Person[] persons = {person1, person2, person3, person4};

        List<Map<String, Object>> list = new ArrayList<Map<String ,Object>>();
        for (int i = 0; i < persons.length; i++) {
            Map<String, Object> map = new HashMap<String, Object>();
            map.put("id", persons[i].getId());
            map.put("name", persons[i].getName());
            map.put("desc", persons[i].getDesc());
            list.add(map);
        }
        //创建适配器
        SimpleAdapter adapter = new SimpleAdapter(
            this,   //当前上下文
            list,   //数据源
            R.layout.list_view, //list_view布局文件
            new String[] {"id", "name", "desc"},    //数据源Map的key键
            new int[] {R.id.imageview, R.id.textview01, R.id.textview02}    //key键对应的value值显示在哪个控件上
        );
        //绑定适配器
        listView.setAdapter(adapter);
        //绑定监听
        listView.setOnItemClickListener(new SimpleAdapterTest());

    }
    //定义内部类，实现OnItemClickListener接口
    class SimpleAdapterTest implements OnItemClickListener {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
            Toast.makeText(MainActivity.this, "您选择了第" + arg2 + "行！", Toast.LENGTH_SHORT).show();
        }

    }

}

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总结： 在Android中有多种适配器，比如：ArrayAdapter、SimpleAdapter、BaseAdapter、SimpleCursorAdapter等，它们就像连接数据源与UI界面之间的桥梁，不同适配器之间的区别在于它们所适配的数据源不同而已。