Android ListView 列表视图

列表显示的三个元素

ListView : 用来显示列表的View

Adapter : 适配器用来把数据映射到ListView 上的中介

Data: 数据将被映射的字符串,图片或者基本组件等资源

根据列表的适配器类型可分为三种: ArrayAdapter, SimpleAdapter ,SimpleCursorAdapter .

ArrayAdapter 最简单 ,只能显示一行字

SimpleAdapter 扩充性好,可以自定义各种效果 ,

SimpleCursorAdapter 可以认为是对数据库的简单结合,可以把数据库的内容以列表的形式显示出来.

ArrayAdapter适配器简单实例:

package com.app.listviewtest;

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.widget.AdapterView;

import android.widget.ArrayAdapter;

import android.widget.ListView;

import android.widget.Toast;

public class MainActivity extends Activity {

	//创建ListView 对象

	private ListView mListView ;

	//添加数据

	List<Object> data;

	private List getData(){

		data = new ArrayList<Object>();

		data.add("Java");

		data.add("android");

		data.add("c");

		data.add("c++");

		return data;

	}

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		mListView = new  ListView(this);//获得组件

		//设置适配器

		mListView.setAdapter(new ArrayAdapter<Object>(this,android.R.layout.simple_expandable_list_item_1,getData()));

		//设置布局 显示listView

		setContentView(mListView);

		mListView.setOnItemClickListener( new AdapterView.OnItemClickListener() {

			@Override

			public void onItemClick(AdapterView<?> parent, View view,

					int position, long id) {

				String text =data.get(position).toString();

				switch (position) {

					case 0 :

						 Toast.makeText(getApplicationContext(),text+"被点击" , 0).show();

						break;

					case 1 :

						Toast.makeText(getApplicationContext(),text+"被点击" , 0).show();

						break;

					case 2 :

						Toast.makeText(getApplicationContext(),text+"被点击" , 0).show();

						break;

					case 3 :

						Toast.makeText(getApplicationContext(),text+"被点击" , 0).show();

						break;

					default :

						break;

				}

			}

		});

	}

	@Override

	public boolean onCreateOptionsMenu(Menu menu) {

		// Inflate the menu; this adds items to the action bar if it is present.

		getMenuInflater().inflate(R.menu.main, menu);

		return true;

	}

}

SimpleAdapter 的简单使用:

布局文件:

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:orientation="horizontal" >

        <LinearLayout

            android:layout_width="match_parent"

            android:layout_height="wrap_content"

            android:orientation="vertical" >

            <ImageView

                android:id="@+id/ImageView1"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

              />

            <TextView

                android:id="@+id/TextView1"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                />

        </LinearLayout>

</LinearLayout>

Java文件:

package com.app.listviewtest;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import android.app.ListActivity;

import android.os.Bundle;

import android.view.Window;

import android.widget.SimpleAdapter;

public class simpleAdapterActivity extends ListActivity {

	//数据源

	private List<Map<String,Object>> getData(){

		List <Map<String,Object>> list = new ArrayList<Map<String,Object>>();

		Map<String,Object> map = new HashMap<String, Object>();

		map.put("ImageView1", R.drawable.ic_launcher);

		map.put("TextView1", "图片一");

		list.add(map);

		map = new HashMap<String, Object>();

		map.put("ImageView1", R.drawable.ic_launcher);

		map.put("TextView1", "图片二");

		list.add(map);

		map = new HashMap<String, Object>();

		map.put("ImageView1", R.drawable.ic_launcher);

		map.put("TextView1", "图片3");

		list.add(map);

		map = new HashMap<String, Object>();

		map.put("ImageView1", R.drawable.ic_launcher);

		map.put("TextView1", "图片4");

		list.add(map);

		return list;

	}

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		//隐藏标题

		requestWindowFeature(Window.FEATURE_NO_TITLE);

		//设置 适配器  (上下文,数据,模板的资源ID,组件对应的资源,xml布局文件中组件的id)

		//public SimpleAdapter(Context context, List<? extends Map<String, ?>> data,int resource, String[] from, int[] to) {}

		SimpleAdapter adapter = new SimpleAdapter(getApplicationContext(), getData(),

				R.layout.simpleadapter_activity,new String[]{"ImageView1","TextView1"},

				new int[] {R.id.ImageView1,R.id.TextView1});

		setListAdapter(adapter);

	}

}

巴特西

Android ListView 列表视图

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