Using Windows XP Visual Styles
Using Microsoft Windows XP, you can now define the visual style or appearance of controls and windows from simple colors to textures and shapes, sometimes called themes. You can control each defined part of a control as well as each part of the non-client (frame and caption) area of a window. The user can then use the Appearance tab in the Windows Control Panel to switch between the classic visual style and other available styles.
A visual style is included with the Windows XP release. Using helper libraries and application programming interfaces (APIs), you can incorporate the Windows XP visual style into your application with few code changes. For more information, see the Platform SDK documentation in the MSDN Library.
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