{Header}
This example shows how to implement a simple Yellow Pages application that consists of a Path, Directory and a Grid.
Navigate to the 'Software' category (Computers and Internet -> Software ) to view the corresponding Yellow Pages entries.
Database: Internet
Tables: directory_categories, directory_items, states
Grid's Before Show event - used to hide the Grid when no matching records are found.
Directory’s Before Show event - used to hide the whole Directory when the user reaches the lowest Directory level and no more subcategories are found.