When working with different types of listboxes such as current selection and array-based, make sure both listboxes use their own process variable name to avoid typing conflict. Take for example when both array-based and current selection listboxes on different forms is given the variable listboxVar. 4D will fail to compile due to the different variable types for each listbox.



As a refresher, 4D will type array-based listboxes with a boolean array while current selection based listboxes will be typed as real. In short, make sure different types of listboxes are given different named process variables to avoid this typing error.