GEOS SDK TechDocs
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5.2 The Scalable User Interface
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5.4 Input
A window is an object that defines an area on the screen in which drawing and user interaction can occur. Windows may be resizable and movable, and automatically clip any drawing so it does not appear outside the window's edges.
The GEOS Window Manager maintains information about the size, shape, and visibility of all the windows in the system. In general, applications do not access the Window Manager directly; instead, generic UI objects and the kernel handle all window manipulation. Several different types of generic objects are "window" objects: GenPrimary is used as an application's primary window, GenInteraction is used for dialog boxes and menus, GenDisplay displays documents in a scrollable window, and GenView is used to create a scrollable graphics window into which an application can draw.
The Window Manager is closely tied to the GEOS Graphic System. These two parts of the system handle all window resizing, reshaping, drawing, and clipping automatically. They also interact with the User Interface's input mechanism to ensure that the proper windows receive the proper input. Applications do not need to know the shape, position, or size of a window when drawing inside it.
Applications can also allocate one or more windows in which they can present data (text, graphics, or other information). Each of these windows is called a View and is an instance of the GenView object (see below). The View manages all scrolling, scaling, sizing, and clipping automatically for the application; programmers don't have to worry about managing scrollbars or window size in order to ensure the proper portion of the data is drawn. Additionally, applications can modify any of the scrolling, scaling, or sizing behavior with a little effort to provide custom functionality.
GEOS SDK TechDocs
|
| 5.2 The Scalable User Interface
| 5.4 Input