Android - 通用 Viewholder

在 iOS 开发中基本不会用到 Viewholder 这种神奇的模式, 所以第一次在 android 中看到还是挺懵逼的,感觉有点逗.
而且每次重复的写 viewholder 感觉很不 geek,所以在google 上搜到别人搜到的…..这一个通用的 viewholder 的方法
挺不错的.

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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;
}
}
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@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;
}