android - CompoundButton.OnCheckedChangeListener() + AlertDialog -

i'm trying work multiple checkboxes inside alert dialog, made it, when click in check, code make boom!

here piece of activity (the alert dialog) extends appcompactactivity , doesn't implements nothing, it's worthy distinguish button cancel , accept working.

additionalbox.setonclicklistener(new onclicklistener() {         @override         public void onclick(view v) {             layoutinflater layoutinflater = layoutinflater.from(productactivity.this);             final view additionalview = layoutinflater.inflate(r.layout.dialog_additionals, null);              // set custom dialog components - text, buttons, accountants             textview titledialog = (textview) additionalview.findviewbyid(r.id.title_additional);             titledialog.settypeface(boldfont);             button buttonaccept = (button) additionalview.findviewbyid(r.id.button_accept);             buttonaccept.settypeface(boldfont);             button buttoncancel = (button) additionalview.findviewbyid(r.id.button_cancel);             buttoncancel.settypeface(boldfont);              alertdialog.builder alertdialogbuilder = new alertdialog.builder(productactivity.this);             alertdialogbuilder.setview(additionalview);             final alertdialog alertd = alertdialogbuilder.create();             alertd.setcanceledontouchoutside(false);             //fill object of additional                 arraylist<additionalbean> additionallist = new arraylist<additionalbean>();                 additionallist.add(new additionalbean("queso", 500, false));                 additionallist.add(new additionalbean("tocineta", 700, false));                 additionallist.add(new additionalbean("salsas",1200,false));                 listview additionallistview = (listview) additionalview.findviewbyid(r.id.list_additional);                 additionaladapter = new additionaladapter(productactivity.this, additionallist);                 additionallistview.setchoicemode(listview.choice_mode_multiple);                 additionallistview.setadapter(additionaladapter);                 additionallistview.setonitemclicklistener(new adapterview.onitemclicklistener() {                      @override                     public void onitemclick(adapterview<?> parent,                                             view view, int position, long id) {                          checkbox chk = (checkbox) productactivity.this.findviewbyid(r.id.additional_check);                         additionalbean bean = additionallistclass.addlist                                 .get(position);                         if (bean.ischecked()) {                             bean.setischecked(false);                             chk.setchecked(false);                         } else {                             bean.setischecked(true);                             chk.setchecked(true);                         }                      }                 });             //end of fill object of additional             buttoncancel.setonclicklistener(new onclicklistener() {                 @override                 public void onclick(view v) {                     alertd.dismiss();                 }             });              buttonaccept.setonclicklistener(new onclicklistener() {                 @override                 public void onclick(view v) {                    // quantity.settext(newquantity.gettext().tostring());                     alertd.dismiss();                 }             });              alertd.show();         }     }); 

then here adapter:

public class additionaladapter extends arrayadapter{ private arraylist<additionalbean> originaldata = null; private context context;  public additionaladapter (context context, arraylist<additionalbean> listarray){     super(context, r.layout.additional_item);     this.context = context;     this.originaldata = listarray ; }  public static class row {     public textview labelname;     public textview labelprice;     public checkbox check; }  @override public int getcount() {     return originaldata.size(); }  @override public additionalbean getitem(int position) {     return originaldata.get(position); }  @override public long getitemid(int position) {     return position; }   @override public view getview(int position, view convertview, viewgroup parent) {    view rowview = convertview;     // reuse views     if (rowview == null) {         layoutinflater inflater = layoutinflater.from(context);         rowview = inflater.inflate(r.layout.additional_item, null);         // configure view holder         row viewholder = new row();          viewholder.labelname = (textview) rowview.findviewbyid(r.id.additional_name);         viewholder.labelprice = (textview) rowview.findviewbyid(r.id.additional_price);         viewholder.check = (checkbox) rowview.findviewbyid(r.id.additional_check);          viewholder.check.setoncheckedchangelistener(new compoundbutton.oncheckedchangelistener() {              @override             public void oncheckedchanged(compoundbutton vw, boolean ischecked) {                 int getposition = (integer) vw.gettag();                 originaldata.get(getposition).setischecked(                         vw.ischecked());              }         });          rowview.settag(viewholder);     }     row holder = (row) rowview.gettag();     final additionalbean itm = originaldata.get(position);     holder.labelname.settext(itm.getname());     holder.labelprice.settext("bs. " + string.valueof(itm.getprice()));     holder.check.setchecked(originaldata.get(position).ischecked());     return rowview; } 

}

the specific error is: java.lang.nullpointerexception: attempt invoke virtual method 'int java.lang.integer.intvalue()' on null object reference @ com.xetux.x_pedidos.modules.product.additionaladapter$1.oncheckedchanged(additionaladapter.java:76)

i tried this solution , doesn't work me

1: android checkbox getchecked (compoundbutton.oncheckedchangelistener (without button click event)) supposed because alert dialog.

and want

i suspect line problem: int getposition = (integer) vw.gettag(); don't see tag set anywhere. can either set tag during binding view, or can example make position variable final - made available listener. `