Linking two Access listboxes

A single listbox is a good way of letting users select an entry from a table. Sometimes though, users' requirements are more complex and they need to be able to make the selection in two stages. The sample form below shows one list box showing a choice of courses and a second box showing the dates when the selected course is running:

Two simple changes to the design will synchronize the two listboxes.

The first is to set the RowSource of the right-hand listbox so that it is based on the value of the left-hand listbox (named lstCourse here):

The second is to make sure that the right-hand list box (named lstDates here) is updated every time that a new selection is made in the left-hand listbox. Put this code into the Click event of the left-hand listbox:

This works because the Click code runs whenever the user changes to a new row in the Courses list box - regardless of whether the change is made by a mouse click or by the cursor keys. Either way, a new list of dates will be created in the right-hand listbox.