android listview不能顺利滚动

Question

您好我正在ListView工作，只有图片看得正确但不能滚动，请检查我的代码并给我适当的答案。

 public View getView(int position, View convertView, ViewGroup parent) {
        View vi = convertView;
     ViewImageItem imghoder ;
        if (convertView == null){
            imghoder =new ViewImageItem();
            vi = inflater.inflate(R.layout.list_row, null);

        imghoder.imgItem = (ImageView) vi.findViewById(R.id.list_image);


        vi.setTag(imghoder);
    } else {
        imghoder =  (ViewImageItem) vi.getTag();
    }
        //imghoder.imgItem.setImageResource(mThumbIds[position]);
        imghoder.imgItem.setImageResource(mThumbIds[position]);


        return vi;
    }



    private static class ViewImageItem {


       ImageView imgItem;


}

please check my full code