Style Sheets and Generic GUI Classes

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For dialogs and controls, a small hierarchy of foundation classes is offered. These foundation classes are displayed on the Dialog Boxes tab page and the Controls tab page of the catalog. You can extend these hierarchies at liberty by adding new subclasses.

If you plan and document dialog and control development ahead of implementation, create generic classes for faster development and easier maintenance. For example, if you know you need 10 similar dialog classes, create a superclass first and make the dialogs subclasses of it. This way you can specify everything that the dialogs have in common at the superclass level.

For info box classes, a number of foundation classes are offered that are independent of your data model. They are called "style sheets":

· Generic

 

· Info Window

 

· Lookup Window

 

· Related Window

 

· Secondary Window

 

· Subtype Window

Specifications made for a style sheet will cascade application-wide to all subclasses of that style. Style sheets are read-only by default, but you can edit them if you first make them read/write.

For example, if you want a Close button on all Info Windows in the application, insert such a button in the Info Window generic class.

Base Table classes allow you to make generic specifications for all info box classes based on the same table. In addition, there are generic classes for each combination of style sheet and base table. For example, the "Lookup PERSON" superclass allows you to make specifications for all Lookup Windows based on PERSON.

Finally, even default classes like the "Persons" info window class are, in a way, generic. Settings applied to the "Persons" info window cascade to all user-defined subclasses of it.