android - When I'm scrolling a list. then click on any view. I'm getting wrong position -

here i'm maintaining list view buttons & edit box. when scroll list , perform onclick operation on button. performed wrongly. when clicked 3rd row selection perform on second row. how can handle

adapter code is

public class itemadapter extends arrayadapter<itemdata> {         context context;         int layoutresourceid;         arraylist<itemdata> data = null;         viewholder holder = null;         private int selectedpos = -1; // init value not-selected          public itemadapter(context context, int layoutresourceid, arraylist<itemdata> data) {             super(context, layoutresourceid, data);             this.layoutresourceid = layoutresourceid;             this.context = context;             this.data = data;         }          public void setselectedposition(int pos) {              selectedpos = pos;             system.out.println("mainactivity.itemadapter.setselectedposition()-----"+selectedpos);             // inform view of change             notifydatasetchanged();         }          public int getselectedposition() {             return selectedpos;         }          public view getview(int position, final view convertview, final viewgroup parent) {             view row = convertview;              if (row == null) {                 layoutinflater inflater = ((activity) context).getlayoutinflater();                 row = inflater.inflate(layoutresourceid, parent, false);                  holder = new viewholder();                 holder._itemname = (textview) row.findviewbyid(r.id.item_name);                 holder._itemprice = (textview) row.findviewbyid(r.id.item_price);                 holder._list_image = (imageview) row.findviewbyid(r.id.list_image);                 holder._plusbutton = (button) row.findviewbyid(r.id.plusbutton);                 holder._minusbutton = (button) row.findviewbyid(r.id.minusbutton);                 holder._cancelbutton = (button) row.findviewbyid(r.id.cancel);                 holder._quantityedittext = (textview) row.findviewbyid(r.id.quantityedittext);                 holder._radio1 = (radiobutton) row.findviewbyid(r.id.firstradio);                 holder._radio2 = (radiobutton) row.findviewbyid(r.id.secondradio);                 holder._radio3 = (radiobutton) row.findviewbyid(r.id.thirdradio);                 system.out.println("mainactivity.itemadapter.getview()-----"+selectedpos);                      holder._plusbutton.setcontentdescription(position + "");                     holder._minusbutton.setcontentdescription(position + "");              }             // } else {             // holder = (viewholder) row.gettag();             // }             final itemdata item_data = data.get(position);             system.out.println("mainactivity.itemadapter.getview()--position---"+position);             system.out.println("mainactivity.itemadapter.getview()--------name------" + item_data.itemnme);             holder._itemname.settext(item_data.itemnme);             holder._plusbutton.setonclicklistener(new onclicklistener() {                 public void onclick(view v) {                     view singleitemview = mainlistview.getchildat(integer.parseint(v.getcontentdescription().tostring()));                     textview edittext = (textview) singleitemview.findviewbyid(r.id.quantityedittext);                     textview pricetaxt = (textview) singleitemview.findviewbyid(r.id.item_price);                     int itemquantity = (integer.parseint(edittext.gettext().tostring())) + 1;                     edittext.settext(string.valueof(itemquantity));                     edittext.invalidate();                     radiobutton button1 = (radiobutton) singleitemview.findviewbyid(r.id.firstradio);                     radiobutton button2 = (radiobutton) singleitemview.findviewbyid(r.id.secondradio);                     radiobutton button3 = (radiobutton) singleitemview.findviewbyid(r.id.thirdradio);                     if (!button1.ischecked() && !button3.ischecked())                         button2.setchecked(true);                 }             });              holder._minusbutton.setonclicklistener(new onclicklistener() {                 public void onclick(view v) {                     view singleitemview = mainlistview.getchildat(integer.parseint(v.getcontentdescription().tostring()));                     textview edittext = (textview) singleitemview.findviewbyid(r.id.quantityedittext);                     textview pricetaxt = (textview) singleitemview.findviewbyid(r.id.item_price);                     int itemquantity = (integer.parseint(edittext.gettext().tostring()));                     if (itemquantity != 0) {                         itemquantity = itemquantity - 1;                     }                     edittext.settext(string.valueof(itemquantity));                     edittext.invalidate();                     radiobutton button1 = (radiobutton) singleitemview.findviewbyid(r.id.firstradio);                     radiobutton button2 = (radiobutton) singleitemview.findviewbyid(r.id.secondradio);                     radiobutton button3 = (radiobutton) singleitemview.findviewbyid(r.id.thirdradio);                     if (itemquantity == 0) {                         button1.setchecked(false);                         button2.setchecked(false);                         button3.setchecked(false);                     }                 }             });              row.settag(holder);             return row;         }      } 

the problem in code in cases when row not null, holder not initialized current element's data , listeners set on holder of previous element or next element. need refactor code fix issue.