Floating Windows

Windows are often placed on the display screen so that one window appears to be behind another. This visual overlapping gives the user an impression of depth. A floating window is so-named because its front-to-back display order (that is, its z-order placement relative to other windows on the screen) makes it appear to float in front of document windows. In Figure 1-1 , the "Clipboard" window appears to float in front of the active and inactive document windows.

Figure 1-1  Floating windows

Because earlier versions of the Window Manager defined only the look of floating windows, not their floating behavior, some applications contain code that implements a floating effect for tool palettes and other such windows. However, your application can now use the Window Manager to automatically sort floating and non-floating windows into separately z-ordered groups, thereby enforcing the proper front-to-back display order.