java - Populating a JComboBox with a selection from another JComboBox -

i’ve got 2 jcomboboxes, 1 displays objects of type category (each category contains unique list) , display list in category.

the aim allow user select category in 1st jcombobox , populate 2nd jcombobox list appropriate user selection.

my current code, before user selection, displays 1st jcombobox objects of category type. 2nd displays list in object. that’s fine. upon user selection, 2nd jcombobox doesn’t anything. continues display same list prior user selection.

here code..

list<category> catlist = control.getcatlist();         edititemcatcombobox.removeallitems();         for(category cat: catlist) //this populates 1st jcombobox         {             edititemcatcombobox.additem(cat);          }         string selectedcat = edititemcatcombobox.getselecteditem().tostring(); //maybe line wrong         //edititemdialog.validate();         (category cat: catlist) //this block should populate 2nd jcombobox         {             if(selectedcat.equals(cat.getcatname()))             {                 list<item> itemlist = cat.getcatitems();                 edititemitemscombobox.removeallitems();                 for(item itm: itemlist)                 {                      edititemitemscombobox.additem(itm);                 }             }         }           edititemdialog.setvisible(true); 

i think should implement itemlistener on first jcombobox edititemcatcombobox contains type category can update second 1 every time select new category

edititemcatcombobox.additemlistener(new itemlistener() {     public void itemstatechanged(itemevent arg0) {         //update second jcombobox     } });