Trackers
The CRectTracker class provides a user interface between rectangular items in your application and your user by providing a variety of display styles. These styles include solid, hatched, or dashed borders; a hatched pattern that covers the item; and resize handles that can be located on the outside or inside of a border. Trackers are often used in conjunction with OLE items, that is, objects derived from COleClientItem. The tracker rectangles give visual cues on the current status of the item.
The MFC OLE sample OCLIENT demonstrates a common interface using trackers and OLE client items from the viewpoint of a container application. For a demonstration of the different styles and abilities of a tracker object, see the MFC general sample TRACKER.
For more information on implementing trackers in your OLE application, see Trackers: Implementing Trackers in Your OLE Application