Android:万能框架——universal-image-loader——GridView异步加载图片

import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ProgressBar;
import com.nostra13.example.universalimageloader.Constants.Extra;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.assist.FailReason;
import com.nostra13.universalimageloader.core.assist.ImageLoadingProgressListener;
import com.nostra13.universalimageloader.core.assist.SimpleImageLoadingListener;

/**
 * 表格视图异步加载
 */
public class ImageGridActivity extends AbsListViewBaseActivity {

	String[] imageUrls;

	DisplayImageOptions options;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.ac_image_grid);

		Bundle bundle = getIntent().getExtras();
		imageUrls = bundle.getStringArray(Extra.IMAGES);

		options = new DisplayImageOptions.Builder()
			.showImageOnLoading(R.drawable.ic_stub) //..the image will be display during image loading
			.showImageForEmptyUri(R.drawable.ic_empty)//..the image will be display if empty URI (null or empty string) 
			.showImageOnFail(R.drawable.ic_error) //..the image will be displayed if some error occurs during requested 
			.cacheInMemory(true) //..Sets whether loaded image will be cached in memory 
			.cacheOnDisc(true) // .. Sets whether loaded image will be cached on disc 
			.considerExifParams(true) // Sets whether ImageLoader will consider EXIF parameters of JPEG image (rotate, flip)
			.bitmapConfig(Bitmap.Config.RGB_565)
			.build(); //Builds configured DisplayImageOptions object 

		listView = (GridView) findViewById(R.id.gridview);
		((GridView) listView).setAdapter(new ImageAdapter());
		listView.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
				startImagePagerActivity(position);
			}
		});
	}

	private void startImagePagerActivity(int position) {
		Intent intent = new Intent(this, ImagePagerActivity.class);
		intent.putExtra(Extra.IMAGES, imageUrls);
		intent.putExtra(Extra.IMAGE_POSITION, position);
		startActivity(intent);
	}

	public class ImageAdapter extends BaseAdapter {
		@Override
		public int getCount() {
			return imageUrls.length;
		}

		@Override
		public Object getItem(int position) {
			return null;
		}

		@Override
		public long getItemId(int position) {
			return position;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			final ViewHolder holder;
			View view = convertView;
			if (view == null) {
				view = getLayoutInflater().inflate(R.layout.item_grid_image, parent, false);
				holder = new ViewHolder();
				assert view != null;
				holder.imageView = (ImageView) view.findViewById(R.id.image);
				holder.progressBar = (ProgressBar) view.findViewById(R.id.progress);
				view.setTag(holder); // 为所须要的组件添加tag标签
			} else {
				holder = (ViewHolder) view.getTag();
			}

			/**
			 * return view后，会增加 “展示的图片任务” 到线程池里
			 * 
			 * uri:目标uri, imageView 目标组件,  options 显示图片条件,
			 * ImageLoadingListener 图片加载监听器, ImageLoadingProgressListener 图片加载进度监听器
			 * progressListener：进度监听器
			 */
			imageLoader.displayImage(imageUrls[position], holder.imageView, options, new SimpleImageLoadingListener() {
										 @Override
										 public void onLoadingStarted(String imageUri, View view) {//开始加载
											 holder.progressBar.setProgress(0);
											 holder.progressBar.setVisibility(View.VISIBLE);
										 }

										 @Override
										 public void onLoadingFailed(String imageUri, View view,
												 FailReason failReason) {//加载失败
											 holder.progressBar.setVisibility(View.GONE);
										 }

										 @Override
										 public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {//加载完成
											 holder.progressBar.setVisibility(View.GONE);
										 }
									 }, new ImageLoadingProgressListener() {
										 @Override
										 public void onProgressUpdate(String imageUri, View view, int current,
												 int total) {
											 holder.progressBar.setProgress(Math.round(100.0f * current / total));
										 }
									 }
			);

			return view;
		}

		class ViewHolder {
			ImageView imageView; //图片
			ProgressBar progressBar; //进度条
		}
	}
}

源文件下载地址：http://pan.baidu.com/s/1bnf6CbX