ViewHolder的简易聪明写法

public class ViewHolder {
		// I added a generic return type to reduce the casting noise in client
		// code
		@SuppressWarnings("unchecked")
		public static <T extends View> T get(View view, int id) {
			SparseArray<View> viewHolder = (SparseArray<View>) view.getTag();
			if (viewHolder == null) {
				viewHolder = new SparseArray<View>();
				view.setTag(viewHolder);
			}
			View childView = viewHolder.get(id);
			if (childView == null) {
				childView = view.findViewById(id);
				viewHolder.put(id, childView);
			}
			return (T) childView;
		}
	}

　　运用泛型讲ViewHolder封装起来

使用方式：

@Override
	public View getView(int position, View convertView, ViewGroup parent) {
	    if (convertView == null) {
	        convertView = LayoutInflater.from(context)
	          .inflate(R.layout.banana_phone, parent, false);
	    }
	    ImageView bananaView = ViewHolder.get(convertView, R.id.banana);
	    TextView phoneView = ViewHolder.get(convertView, R.id.phone);
	 
	    BananaPhone bananaPhone = getItem(position);
	    phoneView.setText(bananaPhone.getPhone());
	    bananaView.setImageResource(bananaPhone.getBanana());
	    return convertView;
	}

　　转载：http://www.eoeandroid.com/thread-321547-1-6.html