android ListView使用的三种方法汇总(通过继承BaseAdapter，使用SimpleAdapter和SimpleCursorAdapter)

android中使用ListView显示列表，共有三种实现方式:

分别是通过继承baseAdapter，直接使用simpleAdapter和simplecursoradapter三种方式

下面我们直接通过代码来看一下实现的过程，代码中有详细的注释，所以，不再详细介绍三种方法的实现方式、

在实现三种方式之前，先定义一个xml文件来显示每一个item

<?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:textSize="30sp"
android:layout_width="0sp"
android:id="@+id/personid"
android:layout_height="wrap_content"
android:layout_weight="1"
/>

<TextView

android:textSize="30sp"
android:layout_weight="3"
android:layout_width="0sp"
android:id="@+id/name"
android:layout_height="wrap_content"
/>

<TextView
android:layout_width="0sp"
android:layout_weight="2"
android:textSize="30sp"

android:id="@+id/balance"
android:layout_height="wrap_content"
/>

</LinearLayout>

第一种：baseadapter

package com.example.sqllite;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class BaseAdapterActivity extends Activity {

ListView list;
List<Person> persons = new ArrayList<Person>();

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list = (ListView) this.findViewById(R.id.list);

// 查询数据库获得person的集合
PersonDAO dao = new PersonDAO(getApplicationContext());
persons = dao.queryAll();

//为list添加adapter
list.setAdapter(new MyAdapter());

//添加监听事件
list.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//parent是点击时间发生的adapter,position是点击的位置，即item的位置
Person p=(Person) parent.getItemAtPosition(position);//因为getItemAtPosition是通过调用getItem来获得
//object,因为在MyAdapter中getItem返回的是person，所以通过
//调用这个方法返回的是person

Toast.makeText(getApplicationContext(), p.getId()+"", 0).show();

}
});

}

//自定义adapter，继承baseadapter
class MyAdapter extends BaseAdapter {

@Override
public int getCount() {
// TODO Auto-generated method stub
return persons.size();//获得adapter中item的数量
}

@Override
public Object getItem(int position) {
return persons.get(position);//获得位于position位置的item
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return persons.get(position).getId();///获得位于position位置的item的ID
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

Person p = persons.get(position);//获得位置为position的person

//创建View 用xml填充View并返回
View view = View.inflate(getApplicationContext(), R.layout.item,
null);

TextView tv1 = (TextView) view.findViewById(R.id.personid);// 如果直接通过findViewById查询查询的并不是View下的，而是mainactivity下的
TextView tv2 = (TextView) view.findViewById(R.id.name);
TextView tv3 = (TextView) view.findViewById(R.id.balance);

// 为view内的三个控件赋值
tv1.setText(p.getId().toString());
tv2.setText(p.getName().toString());
tv3.setText(p.getBalance().toString());

return view;
}

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}

第二种：直接使用simpleadapter

package com.example.sqllite;

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

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 SimpleAdapterActivity extends Activity {

List<Person> list;
ListView view;
List<HashMap<String, Object>> personList ;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

PersonDAO dao = new PersonDAO(getApplicationContext());
list = dao.queryAll();

view = (ListView) this.findViewById(R.id.list);

//list中存放的是map 而map中每个key是属性名称，value是person中的属性值
personList = new ArrayList<HashMap<String, Object>>();

//循环遍历list，将每一个person加入到map中
for (Person p : list) {
HashMap<String,Object> map=new HashMap<String, Object>();
map.put("ida", p.getId());
map.put("namea", p.getName());
map.put("balancea", p.getBalance());
personList.add(map);
}

//为ListView添加adapter,simpleadapter中第二个参数是List<HashMap<String, Object>>
//new String[] { "ida", "namea", "balancea"}代表map中的键值，new int[] { R.id.personid, R.id.balance, R.id.name }
//代表R.layout.item,中的textView的id
view.setAdapter(new SimpleAdapter(getApplicationContext(), personList,
R.layout.item, new String[] { "ida", "namea", "balancea" },
new int[] { R.id.personid, R.id.balance, R.id.name }));

view.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {

HashMap<String,Object> a=(HashMap<String, Object>) parent.getItemAtPosition(position);//因为在simpleadapter中放入的是List<HashMap<String, Object>>，所以返回的是hashmap

Toast.makeText(getApplicationContext(), (String)a.get("namea"),0).show();

}
});

}
}

第三种：直接使用simplecursoradapter

package com.example.sqllite;

import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.Toast;

public class SimpleCursorAdapterActivity extends Activity {

ListView listView;
Cursor c;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);
listView = (ListView) this.findViewById(R.id.list);

PersonDAO dao = new PersonDAO(getApplicationContext());

c = dao.queryCursor();

// 此处查询时id必须为_id
listView.setAdapter(new SimpleCursorAdapter(getApplicationContext(),
R.layout.item, c, new String[] { "_id", "name", "balance" },
new int[] { R.id.personid, R.id.name, R.id.balance }));

listView.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Cursor c = (Cursor) parent.getItemAtPosition(position);// 传入的是Cursor所以返回的是Cursor，源码// return(adapter==null||position< //0)?null:adapter.getItem(position)；

String name = null;
if (c.moveToNext()) {
name = c.getString(c.getColumnIndex("name"));
}

Toast.makeText(getApplicationContext(), name, 0).show();

}
});

}

}

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