Abstract: An operating system provides extensions through which application developers may extend the capabilities of a shell of the operating system. For example, application developers may add menu items to context menus for objects that are visible within an integrated system name space. In addition, developers may add property sheet pages for such objects. Application developers also have the option of providing per-instance icons for each instance of an object. Application developers may provide data object extension handlers for customizing data sources on a per-object class basis and may provide drop target extension handlers on a per-object class basis to customize drop target behavior. Developers may additionally provide copy-hook handlers to regulate file system operations on objects. Developers may also extend the functionality provided by the shell of the operating system by adding their own custom name spaces to the integrated system name space.

Abstract: New varieties of child window controls are provided as system resources that application programs may exploit. The preferred embodiment of the present invention provides a dynamic link library (DLL) for implementing the new child window controls as part of an operating system. The new child window controls include a header bar control for providing header bars in application programs. The new controls also include a hot key control that allows a user to view and edit hot key combinations. The new controls further include a tab control for establishing tabs that differentiate amongst pages in user interfaces provided by application programs. An image list data type is defined and functions are provided for manipulating the image list data type. Image lists include multiple like-sized images that are stored efficiently in a single bitmap.

Abstract: A taskbar is provided that supplies visual cues, such as buttons, for each application having an active window. These visual cues inform a user of the currently active windows and may be used to display the active windows. The taskbar may also include a start menu button that enables a user to gain access to a menu for launching programs, opening documents and controlling system settings. The taskbar is resizable and may be anchored to different locations on a video display. The taskbar may operate in a mode where it is not obscurable by other windows. The taskbar may also be displayed in a mode where it is not displayed when another window is in a non-minimized state.

Abstract: A taskbar is provided that supplies visual cues, such as buttons, for each application having an active window. These visual cues inform a user of the currently active windows and may be used to display the active windows. The taskbar may also include a start menu button that enables a user to gain access to a menu for launching programs, opening documents and controlling system settings. The taskbar is resizable and may be anchored to different locations on a video display. The taskbar may operate in a mode where it is not obscurable by other windows. The taskbar may also be displayed in a mode where it is not displayed when another window is in a non-minimized state.

Abstract: An operating system provides extensions through which application developers may extend the capabilities of a shell of the operating system. For example, application developers may add menu items to context menus for objects that are visible within an integrated system name space. In addition, developers may add property sheet pages for such objects. Application developers also have the option of providing per-instance icons for each instance of an object. Application developers may provide data object extension handlers for customizing data sources on a per-object class basis and may provide drop target extension handlers on a per-object class basis to customize drop target behavior. Developers may additionally provide copy-hook handlers to regulate file system operations on objects. Developers may also extend the functionality provided by the shell of the operating system by adding their own custom name spaces to the integrated system name space.