Tk_SetClass(3) Tk Library Procedures Tk_SetClass(3)
Tk_SetClass, Tk_Class - set or retrieve a window's class
Tk_Window tkwin (in) Token for window.
char *class (in) New class name for window.
Tk_SetClass is called to associate a class with a particular window.
The class string identifies the type of the window; all windows with
the same general class of behavior (button, menu, etc.) should have the
same class. By convention all class names start with a capital letter,
and there exists a Tcl command with the same name as each class (except
all in lower-case) which can be used to create and manipulate windows
of that class. A window's class string is initialized to NULL when the
window is created.
For main windows, Tk automatically propagates the name and class to the
WM_CLASS property used by window managers. This happens either when a
main window is actually created (e.g. in Tk_MakeWindowExist), or when
Tk_SetClass is called, whichever occurs later. If a main window has
not been assigned a class then Tk will not set the WM_CLASS property
for the window.
Tk_Class is a macro that returns the current value of tkwin's class.
The value is returned as a Tk_Uid, which may be used just like a string
pointer but also has the properties of a unique identifier (see the
manual entry for Tk_GetUid for details). If tkwin has not yet been
given a class, then Tk_Class will return NULL.
class, unique identifier, window, window manager