当listview在scrollview中时，不会检查自定义列表视图的android复选框

i have implemented custom list view with check box and textviews. It is working fine when list view is not in scroll but if the rows are increased then listviews is in scroll view that time when i click on check box the checked mark is not staying. here is my code, Please suggest me if anything wrong in that code i have implemented custom list view with check