Tk_CreateWindow (3)

SYNOPSIS

#include <tk.h>
Tk_Window
Tk_CreateWindow(interp, parent, name, topLevScreen)
Tk_Window
Tk_CreateWindowFromPath(interp, tkwin, pathName, topLevScreen)
Tk_DestroyWindow(tkwin)
Tk_MakeWindowExist(tkwin)

ARGUMENTS

Tcl_Interp *topLevScreen 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. char *name in Name to use for this window. Must be unique among all children of the same parent. 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. char *pathName in Name of new window, specified as path name within application (e.g. .a.b.c).

DESCRIPTION

The procedures Tk_CreateWindow and Tk_CreateWindowFromPath are used to create new windows for use in Tk-based applications. Each of the procedures returns a token that can be used to manipulate the window in other calls to the Tk library. If the window couldn't be created successfully, then NULL is returned and interp->result is modified to hold an error message.

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_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 was created by Tk_CreateInternalWindow 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 '\" '\" Copyright (c) 1990-1994 The Regents of the University of California. '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" '\" RCS: @(#) $Id: ManageGeom.3,v 1.2 1998/09/14 18:22:52 stanton Exp $ '\" '\" The definitions below are for supplemental macros used in Tcl/Tk '\" manual entries. '\" '\" .AP type name in/out ?indent? '\" Start paragraph describing an argument to a library procedure. '\" type is type of argument (int, etc.), in/out is either "in", "out", '\" or "in/out" to describe whether procedure reads or modifies arg, '\" and indent is equivalent to second arg of .IP (shouldn't ever be '\" needed; use .AS below instead) '\" '\" .AS ?type? ?name? '\" Give maximum sizes of arguments for setting tab stops. Type and '\" name are examples of largest possible arguments that will be passed '\" to .AP later. If args are omitted, default tab stops are used. '\" '\" .BS '\" Start box enclosure. From here until next .BE, everything will be '\" enclosed in one large box. '\" '\" .BE '\" End of box enclosure. '\" '\" .CS '\" Begin code excerpt. '\" '\" .CE '\" End code excerpt. '\" '\" .VS ?version? ?br? '\" Begin vertical sidebar, for use in marking newly-changed parts '\" of man pages. The first argument is ignored and used for recording '\" the version when the .VS was added, so that the sidebars can be '\" found and removed when they reach a certain age. If another argument '\" is present, then a line break is forced before starting the sidebar. '\" '\" .VE '\" End of vertical sidebar. '\" '\" .DS '\" Begin an indented unfilled display. '\" '\" .DE '\" End of indented unfilled display. '\" '\" .SO '\" Start of list of standard options for a Tk widget. The '\" options follow on successive lines, in four columns separated '\" by tabs. '\" '\" .SE '\" End of list of standard options for a Tk widget. '\" '\" .OP cmdName dbName dbClass '\" Start of description of a specific option. cmdName gives the '\" option's name as specified in the class command, dbName gives '\" the option's name in the option database, and dbClass gives '\" the option's class in the option database. '\" '\" .UL arg1 arg2 '\" Print arg1 underlined, then print arg2 normally. '\" '\" RCS: @(#) $Id: man.macros,v 1.2 1998/09/14 18:39:54 stanton Exp $ '\" '\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages. t .wh -1.3i ^B ^l \n(.l b '\" # Start an argument description AP !"\\$4"" .TP \\$4 \{\ !"\\$2"" .TP \\n()Cu .TP 15