Bug fix: was not incrementing the numerator.
Adding hour, minute and second entries to the DateEntry dialog (might rename to DateTimeEntry therefor). Replacing calls to TextEntry that ask for a date with DateEntry. Adding dialog to view and manipulate listen history. Need to refer to this with a button in the detail pane (i.e., when the user clicks on the most recent listen date).
Replacing simple purchase entry dialog with a purchase history dialog. Implementing Catalog.deletePurchase(). Tested OK.
Bug fix: need to quote strings in SQL
Revising filtering code. Moving menu commands that modify the filter to a new menu. Adding Quick Search, Enter Expression and Clear Filters options.