universalimageloader loading local images

/**
 * 异步加载本地图片工具类
 * 
 * @author tony
 * 
 */
public class LoadLocalImageUtil {
    private LoadLocalImageUtil() {
    }

    private static LoadLocalImageUtil instance = null;

    public static synchronized LoadLocalImageUtil getInstance() {
        if (instance == null) {
            instance = new LoadLocalImageUtil();
        }
        return instance;
    }

    /**
     * 从内存卡中异步加载本地图片
     * 
     * @param uri
     * @param imageView
     */
    public void displayFromSDCard(String uri, ImageView imageView) {
        // String imageUri = "file:///mnt/sdcard/image.png"; // from SD card
        ImageLoader.getInstance().displayImage("file://" + uri, imageView);
    }

    /**
     * 从assets文件夹中异步加载图片
     * 
     * @param imageName
     *            图片名称，带后缀的，例如：1.png
     * @param imageView
     */
    public void dispalyFromAssets(String imageName, ImageView imageView) {
        // String imageUri = "assets://image.png"; // from assets
        ImageLoader.getInstance().displayImage("assets://" + imageName,
                imageView);
    }

    /**
     * 从drawable中异步加载本地图片
     * 
     * @param imageId
     * @param imageView
     */
    public void displayFromDrawable(int imageId, ImageView imageView) {
        // String imageUri = "drawable://" + R.drawable.image; // from drawables
        // (only images, non-9patch)
        ImageLoader.getInstance().displayImage("drawable://" + imageId,
                imageView);
    }

    /**
     * 从内容提提供者中抓取图片
     */
    public void displayFromContent(String uri, ImageView imageView) {
        // String imageUri = "content://media/external/audio/albumart/13"; //
        // from content provider
        ImageLoader.getInstance().displayImage("content://" + uri, imageView);
    }

}