Android 使用自定义Adapter适配ListView之后 怎么样根据点击事件修改item的控件属性

private class MyAdapter extends BaseAdapter {
        private LayoutInflater inflater;
        public MyAdapter(Context context) {
            this.inflater = LayoutInflater.from(context);
        }
        @Override
        public int getCount() {
            return (list.size());
        }
        @Override
        public Object getItem(int position) {
           return(list.get(position));
        }
        @Override
        public long getItemId(int position) {
            return position;
        }
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView==null) {
                convertView =inflater.inflate(R.layout.list_items_layout,null);
                holder=new ViewHolder();
                holder.item_bt_delete=(Button)convertView.findViewById(R.id.list_items_bt_delete);
                holder.item_tv_date=(TextView)convertView.findViewById(R.id.list_items_date);
                holder.item_tv_detail=(TextView)convertView.findViewById(R.id.list_items_detail);
                holder.item_tv_dbnumber=(TextView)convertView.findViewById(R.id.list_items_dbnumber);
                holder.item_tv_number=(TextView)convertView.findViewById(R.id.list_items_number);
                convertView.setTag(holder);
            }else{
                holder=(ViewHolder)convertView.getTag();
            }
            //配置数据
            holder.item_tv_detail.setText(list.get(position).get("detail").toString());
           holder.item_tv_date.setText(list.get(position).get("date").toString());
           holder.item_tv_dbnumber.setText(list.get(position).get("dbnumber").toString());
            return convertView;
        }
         public final class ViewHolder{
              public Button item_bt_delete;
              public TextView item_tv_detail;
              public TextView item_tv_date;
              public TextView item_tv_dbnumber;
              public TextView item_tv_number;
         }
    }

在MainActivity中，配置listView

 adapter=new MyAdapter(this);
        listView.setAdapter(adapter);
 listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                //*********************************
                return false;
            }
        });

求问*里面应该怎么写 才能去修改对应position位置上Button的visibility值？