使用开源imageLoader优化listview加载大量本地图片的demo

转载：

package com.example.listviewdemo;

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

import android.database.Cursor;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.assist.ImageLoadingListener;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;
import com.smalt.smaltmap.utils.GlobalConstant;

/** * * @Title: * @Description:ListView显示大量图片 * @Copyright: Copyright (c) 2014 * @Company: * @author: Administrator * @version: 1.0.0.0 * @Date: 2014-2-14 */
public class MainActivity01 extends AbsListViewBaseActivity {
    DisplayImageOptions options; // 配置图片加载及显示选项
    ListView lvShow;
    /** * 存储图片地址 */
    ArrayList<String> listImgPath;
    String[] imageUriArray;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lvShow = (ListView) findViewById(R.id.lv_show);
        // 扫描内存中图片并存入list

        listImgPath = getImgPathList();
        if (listImgPath.size() < 1) {
            GlobalConstant.i("sd卡中无图片");
        } else {
            // list转成数组
            imageUriArray = (String[]) listImgPath
                    .toArray(new String[listImgPath.size()]);
            // 配置图片加载及显示选项（还有一些其他的配置，查阅doc文档吧）
            options = new DisplayImageOptions.Builder()
                    .showStubImage(R.drawable.ic_launcher) // 在ImageView加载过程中显示图片
                    .showImageForEmptyUri(R.drawable.ic_launcher) // image连接地址为空时
                    .showImageOnFail(R.drawable.ic_launcher) // image加载失败
                    .cacheInMemory(true) // 加载图片时会在内存中加载缓存
                    .cacheOnDisc(true) // 加载图片时会在磁盘中加载缓存
                    .displayer(new RoundedBitmapDisplayer(20)) // 设置用户加载图片task(这里是圆角图片显示)
                    .build();
            // 加载适配器
            lvShow.setAdapter(new AdapterList());
        }

    }


    @Override
    public void onBackPressed() {
        AnimateFirstDisplayListener.displayedImages.clear();
        super.onBackPressed();
    }

    /** * * 获取图片地址列表 * * @return list */
    private ArrayList<String> getImgPathList() {
        ArrayList<String> list = new ArrayList<String>();
        Cursor cursor = getContentResolver().query(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                new String[] { "_id", "_data" }, null, null, null);
        while (cursor.moveToNext()) {
            list.add(cursor.getString(1));// 将图片路径添加到list中
        }
        cursor.close();
        return list;
    }

    /** 图片加载监听事件 **/
    private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {

        static final List<String> displayedImages = Collections
                .synchronizedList(new LinkedList<String>());

        @Override
        public void onLoadingComplete(String imageUri, View view,
                Bitmap loadedImage) {
            if (loadedImage != null) {
                ImageView imageView = (ImageView) view;
                boolean firstDisplay = !displayedImages.contains(imageUri);
                if (firstDisplay) {
                    FadeInBitmapDisplayer.animate(imageView, 500); // 设置image隐藏动画500ms
                    displayedImages.add(imageUri); // 将图片uri添加到集合中
                }
            }
        }
    }

    /** * * @Title: * @Description:listview适配器 * @Copyright: Copyright (c) 2014 * @Company: * @author: Administrator * @version: 1.0.0.0 * @Date: 2014-2-14 */
    class AdapterList extends BaseAdapter {
        private ImageLoadingListener animateFirstListener = new AnimateFirstDisplayListener();



        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return imageUriArray.length;
        }

        /** * 构造方法 */
        public AdapterList() {
            // TODO Auto-generated constructor stub
        }


        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return arg0;
        }

        /* * (non-Javadoc) * * @see android.widget.Adapter#getItemId(int) */
        @Override
        public long getItemId(int arg0) {
            // TODO Auto-generated method stub
            return arg0;
        }

        /* * (non-Javadoc) * * @see android.widget.Adapter#getView(int, android.view.View, * android.view.ViewGroup) */
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView == null) {
                holder = new ViewHolder();
                // 初始化绑定控件
                convertView = getLayoutInflater().inflate(R.layout.layout_item, null);
                holder.imgShow = (ImageView) findViewById(R.id.img_show);
                holder.tvShow = (TextView) findViewById(R.id.tv_show);
                // add to convertView
                convertView.setTag(holder);
            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            // 设置img，text具体显示的内容

            holder.tvShow.setText("fuck" + (position));

            imageLoader.displayImage(imageUriArray[position], holder.imgShow,
                    options, animateFirstListener);
            return convertView;
        }
    }

    static class ViewHolder {
        ImageView imgShow;
        TextView tvShow;
    }
}

demo下载:

https://drive.google.com/file/d/0B3vXJifsRl4bTk8wUFpyNk9lNEU/edit?usp=sharing