网络获取图片（缓存）

package com.hsx.imageloader.adapter;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;import com.hsx.imageloader.listener.AnimateFirstDisplayListener;import com.nostra13.universalimageloader.core.DisplayImageOptions;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.assist.ImageLoadingListener;import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;import com.hsx.imageloader.R;public class ItemAdapter extends BaseAdapter {DisplayImageOptions options;private ImageLoadingListener animateFirstListener = new AnimateFirstDisplayListener();String[] imageUrls;Context context;public ItemAdapter(String[] imageUrls, Context context) {super();this.imageUrls = imageUrls;this.context = context;options = new DisplayImageOptions.Builder().showStubImage(R.drawable.ic_launcher)//设置图片在下载期间显示的图片.showImageForEmptyUri(R.drawable.ic_launcher)//设置图片Uri为空或是错误的时候显示的图片.showImageOnFail(R.drawable.ic_launcher)//设置图片加载/解码过程中错误时候显示的图片.cacheInMemory(true)//是否緩存都內存中.cacheOnDisc(true)//是否緩存到sd卡上.displayer(new RoundedBitmapDisplayer(20)).build();}private class ViewHolder {public TextView text;public ImageView image;}@Overridepublic int getCount() {return imageUrls.length;}@Overridepublic Object getItem(int position) {return position;}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(final int position, View convertView, ViewGroup parent) {final ViewHolder holder;if (convertView == null) {LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);convertView = inflater.inflate(R.layout.item_list_image, 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));// ImageLoaderImageLoader imageLoader = ImageLoader.getInstance();imageLoader.displayImage(imageUrls[position], holder.image, options, animateFirstListener);return convertView;}}