Basically, this feature means that the keyboard input focus always follows the mouse pointer. That is, if you move the mouse, the window under the mouse pointer will be given the input focus (which means that also the title bar will be made active).

This behavior is very common with the various window managers running on the X-Window windowing system used with the many flavors of UNIX, and Linux has inherited this also. Since many people prefer to have this behavior with &os2; too (including myself), this has been included with &xwp;.

This feature can be configured in the "Mouse" object, which usually resides in your "System Setup" folder. On the "Movement" page in that object, there are several settings. Press the "Help" button on that page to find out more.

Note: That page is only visible if the XWPMouse class is installed and the &xwp; hook has been enabled in "&xwp; Setup".

The main advantage of this feature is that for one, you don't have to click into a window to be able to use the keyboard with it. Also, if you have disabled the "Bring window to top" setting on the "Mouse hook" page, you can even type into a window which is not the topmost window, which is impossible without the "Sliding focus" feature. This takes a bit of getting used to, but this can be very handy when several windows are opened and you need to view one window's information while typing into another.

Notes

1. There's no way to make this feature work properly with seamless &winos2; windows. The 16-bit Windows graphics engine (Graphical Device Interface, GDI) is not capable of differentiating between a "topmost" and an "active" window; it simply assumes that the topmost window must always be the active one. This limitation applies to seamless &winos2; windows also, which use the 16-bit Windows graphics engine internally.

   For this reason, there is a special setting on the "Movement" page in the "Mouse" settings notebook for &winos2; windows. You can either decide to always bring &winos2; windows to the top, or to ignore them completely. It is however not possible to make them active without bringing them to the top. Otherwise you'd get really strange repainting errors on your screen, because the GDI would repaint an active &winos2; window completely even if other windows are on top of it (because it assumes it must be the topmost window).

   Of course, full-screen &winos2; sessions are not affected by &xwp; in any way, because the &xwp; PM hook does not deal with &winos2; fullscreen sessions.

2. While the PM window list (or tasklist) is showing on the screen, the sliding focus feature is temporarily disabled. This is necessary because the window list automatically disappears when it loses the keyboard focus. If the sliding focus weren't disabled while the window list is showing, it would become difficult to do anything with the window list at all, because it would kept disappearing if the mouse pointer was not over it.