oracular (3) Tk_Class.3tk.gz

NAME

       Tk_SetClass, Tk_Class - set or retrieve a window's class

SYNOPSIS

       #include <tk.h>

       Tk_SetClass(tkwin, class)

       Tk_Uid
       Tk_Class(tkwin)

ARGUMENTS

       Tk_Window tkwin (in)           Token for window.

       char *class (in)               New class name for window.
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DESCRIPTION

       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.

KEYWORDS

       class, unique identifier, window, window manager