android 公用的ViewHolder

<span style="font-size:14px;">package com.example.aaa;

import android.util.SparseArray;
import android.view.View;

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;
    }
    //adapter的getview()方法中调用示例：
//    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;
//    }
}</span>