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RGtk2 (version 2.20.31)

gtkWindowGetPosition: gtkWindowGetPosition

Description

This function returns the position you need to pass to gtkWindowMove to keep window in its current position. This means that the meaning of the returned value varies with window gravity. See gtkWindowMove for more details.

Usage

gtkWindowGetPosition(object)

Arguments

object

Value

A list containing the following elements:
root.x
return location for X coordinate of gravity-determined reference point. [ out ]
root.y
return location for Y coordinate of gravity-determined reference point. [ out ]

Details

If you haven't changed the window gravity, its gravity will be GDK_GRAVITY_NORTH_WEST. This means that gtkWindowGetPosition gets the position of the top-left corner of the window manager frame for the window. gtkWindowMove sets the position of this same top-left corner. gtkWindowGetPosition is not 100% reliable because the X Window System does not specify a way to obtain the geometry of the decorations placed on a window by the window manager. Thus GTK+ is using a "best guess" that works with most window managers. Moreover, nearly all window managers are historically broken with respect to their handling of window gravity. So moving a window to its current position as returned by gtkWindowGetPosition tends to result in moving the window slightly. Window managers are slowly getting better over time. If a window has gravity GDK_GRAVITY_STATIC the window manager frame is not relevant, and thus gtkWindowGetPosition will always produce accurate results. However you can't use static gravity to do things like place a window in a corner of the screen, because static gravity ignores the window manager decorations. If you are saving and restoring your application's window positions, you should know that it's impossible for applications to do this without getting it somewhat wrong because applications do not have sufficient knowledge of window manager state. The Correct Mechanism is to support the session management protocol (see the "GnomeClient" object in the GNOME libraries for example) and allow the window manager to save your window sizes and positions.