android ViewHolder优化

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大家通常怎么写ViewHolder呢？

        ViewHolder holder = null;        if(convertView == null){                convertView = mInflater.inflate(R.layout.xxx null);                holder = new ViewHolder();                 holder.tvXXX = (TextView)findViewById(R.id.xxx);                //...一连串的findViewById        }        else{                holder = (ViewHolder) convertView.getTag();          }         private static class ViewHolder{                TextView tvXXX;                //很多view的定义        }

这么写一次还行，但问题是总有很多很多的ViewAdapter要这么写，
ViewHolder这么写（只提供一个静态方法，其实可以加一个私有构造函数防止外部实例化），代码很简单，看过就明白了

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;    }}

在getView里这样

@Overridepublic 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;}

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