Windows

• A window in MacProlog can be a program window (prog), a display window (disp), a control window (ctrl), a graphics window (grap) or a clipboard window (clip)
• A program window may contain edit-able text and can be compiled while a display window cannot be edited or compiled (only for text)
• Dialog windows used to give information to, or accept input from the user during program execution. A dialog window may be of a predefined format, or can be customised - example of predefined is the ask in bank balance
• A control window may contain any number of items for interaction with the user, such as buttons, check boxes, edit fields and all items available in a dialog window
• MacProlog comes with a Graphics Description Language (GDL), used for the placement and sizing of graphical objects. These graphical objects are displayed in graphic windows

Windows are divided according to their functionality. The type of window active at any stage is determined by what is required of the user (or what needs to be displayed).

A user interface is a very important part of a program and should not be tacked on as an after thought. Rather, like any other aspect of your program, it should be engineered! (by considering user requirements, program specification and most importantly, program style).

Before we look at the different types of windows present in more details - consider the types of operations performable on all windows :

 
• Window Management in MacProlog