Provided by: tk8.4-doc_8.4.20-7_all 
NAME
Tk_CreateWindow, Tk_CreateWindowFromPath, Tk_DestroyWindow, Tk_MakeWindowExist - create or delete window
SYNOPSIS
#include <tk.h>
Tk_Window
Tk_CreateWindow(interp, parent, name, topLevScreen)
Tk_Window
Tk_CreateAnonymousWindow(interp, parent, topLevScreen)
Tk_Window
Tk_CreateWindowFromPath(interp, tkwin, pathName, topLevScreen)
Tk_DestroyWindow(tkwin)
Tk_MakeWindowExist(tkwin)
ARGUMENTS
Tcl_Interp *interp (out) Tcl interpreter to use for error reporting. If no error occurs,
then *interp isn't modified.
Tk_Window parent (in) Token for the window that is to serve as the logical parent of the
new window.
CONST char *name (in) Name to use for this window. Must be unique among all children of
the same parent.
CONST char *topLevScreen (in) Has same format as screenName. If NULL, then new window is
created as an internal window. If non-NULL, new window is created
as a top-level window on screen topLevScreen. If topLevScreen is
an empty string (``'') then new window is created as top-level
window of parent's screen.
Tk_Window tkwin (in) Token for window.
CONST char *pathName (in) Name of new window, specified as path name within application
(e.g. .a.b.c).
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DESCRIPTION
The procedures Tk_CreateWindow, Tk_CreateAnonymousWindow, and Tk_CreateWindowFromPath are used to create 2
new windows for use in Tk-based applications. Each of the procedures returns a token that can be used to 2
manipulate the window in other calls to the Tk library. If the window couldn't be created successfully, 2
then NULL is returned and interp->result is modified to hold an error message. 2
Tk supports two different kinds of windows: internal windows and top-level windows. An internal window
is an interior window of a Tk application, such as a scrollbar or menu bar or button. A top-level window
is one that is created as a child of a screen's root window, rather than as an interior window, but which
is logically part of some existing main window. Examples of top-level windows are pop-up menus and
dialog boxes.
New windows may be created by calling Tk_CreateWindow. If the topLevScreen argument is NULL, then the
new window will be an internal window. If topLevScreen is non-NULL, then the new window will be a top-
level window: topLevScreen indicates the name of a screen and the new window will be created as a child
of the root window of topLevScreen. In either case Tk will consider the new window to be the logical
child of parent: the new window's path name will reflect this fact, options may be specified for the new
window under this assumption, and so on. The only difference is that new X window for a top-level window
will not be a child of parent's X window. For example, a pull-down menu's parent would be the button-
like window used to invoke it, which would in turn be a child of the menu bar window. A dialog box might
have the application's main window as its parent.
Tk_CreateAnonymousWindow differs from Tk_CreateWindow in that it creates an unnamed window. This window
will be manipulable only using C interfaces, and will not be visible to Tcl scripts. Both interior
windows and top-level windows may be created with Tk_CreateAnonymousWindow.
Tk_CreateWindowFromPath offers an alternate way of specifying new windows. In Tk_CreateWindowFromPath
the new window is specified with a token for any window in the target application (tkwin), plus a path
name for the new window. It produces the same effect as Tk_CreateWindow and allows both top-level and
internal windows to be created, depending on the value of topLevScreen. In calls to
Tk_CreateWindowFromPath, as in calls to Tk_CreateWindow, the parent of the new window must exist at the
time of the call, but the new window must not already exist.
The window creation procedures don't actually issue the command to X to create a window. Instead, they
create a local data structure associated with the window and defer the creation of the X window. The
window will actually be created by the first call to Tk_MapWindow. Deferred window creation allows
various aspects of the window (such as its size, background color, etc.) to be modified after its
creation without incurring any overhead in the X server. When the window is finally mapped all of the
window attributes can be set while creating the window.
The value returned by a window-creation procedure is not the X token for the window (it can't be, since X
hasn't been asked to create the window yet). Instead, it is a token for Tk's local data structure for
the window. Most of the Tk library procedures take Tk_Window tokens, rather than X identifiers. The
actual X window identifier can be retrieved from the local data structure using the Tk_WindowId macro;
see the manual entry for Tk_WindowId for details.
Tk_DestroyWindow deletes a window and all the data structures associated with it, including any event
handlers created with Tk_CreateEventHandler. In addition, Tk_DestroyWindow will delete any children of
tkwin recursively (where children are defined in the Tk sense, consisting of all windows that were
created with the given window as parent). If tkwin is an internal window, then event handlers interested
in destroy events are invoked immediately. If tkwin is a top-level or main window, then the event
handlers will be invoked later, after X has seen the request and returned an event for it.
If a window has been created but hasn't been mapped, so no X window exists, it is possible to force the
creation of the X window by calling Tk_MakeWindowExist. This procedure issues the X commands to
instantiate the window given by tkwin.
KEYWORDS
create, deferred creation, destroy, display, internal window, screen, top-level window, window
Tk 4.2 Tk_CreateWindow(3tk)