@Override   public View getView(int position, View convertView, ViewGroup parent) {         …………     ViewHolder VH = null;         …………      VH.mImageView.setTag(position);      VH.mThumb.setImageDrawable(imageLoader.loadDrawable(position,        new ImageCallback() {          public void imageLoaded(Drawable imageDrawable, int position) {            ImageView imageViewByTag = (ImageView) mList.findViewWithTag(position);            if (imageViewByTag != null) {              imageViewByTag.setImageDrawable(imageDrawable);              }            }         }));  }  private static LruCache<Long, Drawable> mCache = new LruCache<Long, Drawable>(100);  public class AsyncImageLoader {    public Drawable loadDrawable(final int position, final ImageCallback callback){      Drawable d = null;      d = mCache.get(position);      if (d == null) {        final Handler handler=new Handler(){          @Override          public void handleMessage(Message msg) {            callback.imageLoaded((Drawable) msg.obj, position);          }        };        Thread t = new Thread(){          public void run() {            Drawable drawable = Utils.getDrawable(mContext, position, 1, mMyDefaultIcon);            Drawable value = mCache.get(position);//cache有可能已經被更改了，所以重新取一次            if (value == null) {              mCache.put(position, drawable);            } else {              drawable = value;            }            handler.sendMessage(handler.obtainMessage(0,drawable));          };        };        t.setPriority(Thread.MIN_PRIORITY);        t.start();        return mMyDefaultIcon;      } else {        return d;      }    }  }  public interface ImageCallback{    public void imageLoaded(Drawable imageDrawable, int position);  }