Trigger DropdownBox change event

I have a DropdownBox with items binded to a column from a xsodata service. I attached a change event that updates a table when the value in the DropdownBox is changed; but when the DropdownBox is first created, SAPUI5 selects the first item by default and it doesn't fire the event I created. This causes the table to display incorrect data. 

Does anyone know how to trigger the change event when the DropdownBox is first created or is it possible to get the Items in the Dropdown box in the createContent function?

Thanks!