how to select combox items to be selected when edit employee

I have employee and an employee have workd fro multiple dept. save part is working but when i click on link fro edting employee the combox items shpould be selected 
Hello Subudhi,

Your list of items must have an indication if the employee is working in the department (Boolean).
Binding the List to the ListBox widget you need to bind the Boolean attribute to "Selection Attribute" property (and Selection Mode = Multiple).

Hope it helps!

Thanks Anselmo,
its working as expected . when edit an employee same items under the combobox should be alreday selected while loding for edit. so that what are the dept that an employee worked for .
so that i can select fresh selection when i resubmit .