java - JList and JScrollPane don't respond/are inaccessible -

i trying implement basic gui user can move objects 1 jlist another. jlists should contained within scrollpane size not issue. basic functionality good, items move , remove button presses. however, jlist , jscrollpane items added display correctly , detect if scrollbar necessary not interact @ user reason. user cannot select jlist nor scroll scrollpane. rough idea of code below;

public void createjlist(type[] datatolist){     somescrollpane = new jscrollpane(); //somescrollpane private global     somescrollpane.setbounds(numbers here);     this.add(somescrollpane); //this custom frame class     alist = new jlist<type>(datatolist);     somescrollpane.setviewportview(alist); 

this rough idea. add listener @ stage since scrollpane isn't working either may leave later. use code both working , non-responsive jlists , scrollpanes same.

of note, call method everytime list want display changed. i'm thinking maybe because jlist , scrollpane keep getting created, broken?