Android图片异步加载框架Android-Universal-Image-Loader

实例：UniversalImageLoaderDemo

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.rainsong.universalimageloaderdemo"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="19" />

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.INTERNET" />
    
    <application
        android:name="com.rainsong.universalimageloaderdemo.UILApplication"
        android:allowBackup="true"
        android:icon="@drawable/logo"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.rainsong.universalimageloaderdemo.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
    tools:context=".MainActivity" >

    <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    </ListView>

</LinearLayout>

布局文件：item_list.xml

<?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" >

	<ImageView
		android:id="@+id/image"
		android:layout_width="72dip"
		android:layout_height="72dip"
		android:layout_margin="3dip"
		android:adjustViewBounds="true"
		android:contentDescription="@string/descr_image"
		android:scaleType="centerCrop" />

	<TextView
		android:id="@+id/text"
		android:layout_width="fill_parent"
		android:layout_height="wrap_content"
		android:layout_gravity="start|center_vertical"
		android:layout_marginLeft="20dip"
		android:textSize="22sp" />

</LinearLayout>

package com.rainsong.universalimageloaderdemo;

import java.io.File;

import com.nostra13.universalimageloader.cache.disc.impl.UnlimitedDiscCache;
import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
import com.nostra13.universalimageloader.cache.memory.impl.UsingFreqLimitedMemoryCache;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.assist.QueueProcessingType;
import com.nostra13.universalimageloader.core.download.BaseImageDownloader;
import com.nostra13.universalimageloader.utils.StorageUtils;

import android.app.Application;
import android.content.Context;

public class UILApplication extends Application {

	@Override
	public void onCreate() {
		super.onCreate();
		initImageLoader(getApplicationContext());
	}

	public static void initImageLoader(Context context) {
		//缓存文件的目录
		File cacheDir = StorageUtils.getOwnCacheDirectory(context, "universalimageloader/Cache"); 
		ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(context)
				.memoryCacheExtraOptions(480, 800) // max width, max height，即保存的每个缓存文件的最大长宽 
				.threadPoolSize(3) //线程池内线程的数量
				.threadPriority(Thread.NORM_PRIORITY - 2)
				.denyCacheImageMultipleSizesInMemory()
				.diskCacheFileNameGenerator(new Md5FileNameGenerator()) //将保存的时候的URI名称用MD5 加密
				.memoryCache(new UsingFreqLimitedMemoryCache(2 * 1024 * 1024))
				.memoryCacheSize(2 * 1024 * 1024) // 内存缓存的最大值
				.diskCacheSize(50 * 1024 * 1024)  // SD卡缓存的最大值
				.tasksProcessingOrder(QueueProcessingType.LIFO)
				// 由原先的discCache -> diskCache
				.diskCache(new UnlimitedDiscCache(cacheDir))//自定义缓存路径  
				.imageDownloader(new BaseImageDownloader(context, 5 * 1000, 30 * 1000)) // connectTimeout (5 s), readTimeout (30 s)超时时间  
				.writeDebugLogs() // Remove for release app
				.build();
		//全局初始化此配置  
		ImageLoader.getInstance().init(config);
	}
}

Java源代码文件：MainActivity.java

package com.rainsong.universalimageloaderdemo;

import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
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 ImageLoader imageLoader;
	private ListView lv;
	private String[] imageUrls;
	private DisplayImageOptions options;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		imageLoader = ImageLoader.getInstance();
		lv = (ListView)findViewById(R.id.list);
		
		imageUrls = Constants.images;

		// 使用DisplayImageOptions.Builder()创建DisplayImageOptions
		options = new DisplayImageOptions.Builder()
				.showImageOnLoading(R.drawable.ic_stub) // 设置图片下载期间显示的图片
				.showImageForEmptyUri(R.drawable.ic_empty) // 设置图片Uri为空或是错误的时候显示的图片
				.showImageOnFail(R.drawable.ic_error) // 设置图片加载或解码过程中发生错误显示的图片
				.cacheInMemory(true) // 设置下载的图片是否缓存在内存中
				.cacheOnDisk(true) // 设置下载的图片是否缓存在SD卡中
				.displayer(new RoundedBitmapDisplayer(20)) // 设置成圆角图片
				.build(); // 构建完成
		lv.setAdapter(new ItemListAdapter());
	}

	@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;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
			case R.id.item_clear_memory_cache:
				ImageLoader.getInstance().clearMemoryCache();
				return true;
			case R.id.item_clear_disc_cache:
				ImageLoader.getInstance().clearDiskCache();
				return true;
			default:
				return false;
		}
	}

	class ItemListAdapter extends BaseAdapter {
		@Override
		public int getCount() {
			// TODO Auto-generated method stub
			return imageUrls.length;
		}

		@Override
		public Object getItem(int position) {
			// TODO Auto-generated method stub
			return imageUrls[position];
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			// TODO Auto-generated method stub
			ViewHolder holder = null;
			if (convertView == null) {
				convertView = getLayoutInflater().inflate(R.layout.item_list, parent, false);
				holder = new ViewHolder();
				holder.text = (TextView) convertView.findViewById(R.id.text);
				holder.image = (ImageView) convertView.findViewById(R.id.image);
				convertView.setTag(holder);
			} else {
				holder = (ViewHolder) convertView.getTag();
			}
			holder.text.setText("Item " + (position + 1));
			imageLoader.displayImage(imageUrls[position], holder.image, options);
			return convertView;
		}

		@Override
		public long getItemId(int position) {
			// TODO Auto-generated method stub
			return position;
		}

		class ViewHolder {
			public ImageView image;
			public TextView text;
		}
	}

}

Android图片异步加载框架Android-Universal-Image-Loader

原文：http://blog.csdn.net/hantangsongming/article/details/41961749