使用自定义Layout代替ViewHolder

ListView是非常常用android 控件，而对于ListView的优化，大家都想起了viewHolder模式了，很多人都写得滚瓜烂熟了。然而在Customizing Android ListView Rows by Subclassing中提到ViewHolder是一种愚昧的方式。为什么？以下是viewHolder模式的问题Create a layout for your row view.Create a “holder” class with fields to store child views of the row.For each new inflated row, create a holder instance and assign its fields to the results of calling 

findViewById(int)

 for each child view.Set the instance of the holder as the top-level view’s tag with 

setTag(Object).

Reuse (and cast) the holder object for reused row views.那怎么办？作者在文章中提出了新的思路，通过自定义的Layout来代替ViewHolder关键代码：自定义Layout：MyLayoutpublic classMyLayout extendsRelativeLayout {

TextView tv_title;

public MyLayout(Context context) {
super(context);
init(context);
}

private void init(Context context) {
View view = LayoutInflater.from(context).inflate(R.layout.item_demo, this);
tv_title = (TextView) view.findViewById(R.id.tv_title);
}

public void setData(String title) {
tv_title.setText(title);
}
}

MyAdapter

public class MyAdapter extends BaseAdapter {private Context mContext;private List<String> mList;public MyAdapter(Context context, List<String> list) {mContext = context;mList = list;}@Overridepublic int getCount() {return mList == null ? 0 : mList.size();}@Overridepublic Object getItem(int position) {return null;}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {MyLayout myLayout;if (convertView != null && convertView instanceof MyLayout) {myLayout = (MyLayout) convertView;} else {myLayout = new MyLayout(mContext);}myLayout.setData(mList.get(position));return myLayout;}}

done