1 /*
2  * tkGeometry.c --
3  *
4  *	This file contains generic Tk code for geometry management (stuff
5  *	that's used by all geometry managers).
6  *
7  * Copyright © 1990-1994 The Regents of the University of California.
8  * Copyright © 1994-1995 Sun Microsystems, Inc.
9  *
10  * See the file "license.terms" for information on usage and redistribution of
11  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
12  */
13 
14 #include "tkInt.h"
15 
16 /*
17  * Data structures of the following type are used by Tk_MaintainGeometry. For
18  * each content managed by Tk_MaintainGeometry, there is one of these structures
19  * associated with its container.
20  */
21 
22 typedef struct MaintainContent {
23     Tk_Window content;		/* The content window being positioned. */
24     Tk_Window container;		/* The container that determines content's
25 				 * position; it must be a descendant of
26 				 * content's parent. */
27     int x, y;			/* Desired position of content relative to
28 				 * container. */
29     int width, height;		/* Desired dimensions of content. */
30     struct MaintainContent *nextPtr;
31 				/* Next in list of Maintains associated with
32 				 * container. */
33 } MaintainContent;
34 
35 /*
36  * For each window that has been specified as a content to Tk_MaintainGeometry,
37  * there is a structure of the following type:
38  */
39 
40 typedef struct MaintainContainer {
41     Tk_Window ancestor;		/* The lowest ancestor of this window for
42 				 * which we have *not* created a
43 				 * StructureNotify handler. May be the same as
44 				 * the window itself. */
45     int checkScheduled;		/* Non-zero means that there is already a call
46 				 * to MaintainCheckProc scheduled as an idle
47 				 * handler. */
48     MaintainContent *contentPtr;	/* First in list of all content associated with
49 				 * this container. */
50 } MaintainContainer;
51 
52 /*
53  * Prototypes for static procedures in this file:
54  */
55 
56 static void		MaintainCheckProc(ClientData clientData);
57 static void		MaintainContainerProc(ClientData clientData,
58 			    XEvent *eventPtr);
59 static void		MaintainContentProc(ClientData clientData,
60 			    XEvent *eventPtr);
61 
62 /*
63  *--------------------------------------------------------------
64  *
65  * Tk_ManageGeometry --
66  *
67  *	Arrange for a particular procedure to manage the geometry of a given
68  *	content window.
69  *
70  * Results:
71  *	None.
72  *
73  * Side effects:
74  *	Proc becomes the new geometry manager for tkwin, replacing any
75  *	previous geometry manager. The geometry manager will be notified (by
76  *	calling procedures in *mgrPtr) when interesting things happen in the
77  *	future. If there was an existing geometry manager for tkwin different
78  *	from the new one, it is notified by calling its lostContentProc.
79  *
80  *--------------------------------------------------------------
81  */
82 
83 void
Tk_ManageGeometry(Tk_Window tkwin,const Tk_GeomMgr * mgrPtr,ClientData clientData)84 Tk_ManageGeometry(
85     Tk_Window tkwin,		/* Window whose geometry is to be managed by
86 				 * proc. */
87     const Tk_GeomMgr *mgrPtr,	/* Static structure describing the geometry
88 				 * manager. This structure must never go
89 				 * away. */
90     ClientData clientData)	/* Arbitrary one-word argument to pass to
91 				 * geometry manager procedures. */
92 {
93     TkWindow *winPtr = (TkWindow *) tkwin;
94 
95     if ((winPtr->geomMgrPtr != NULL) && (mgrPtr != NULL)
96 	    && ((winPtr->geomMgrPtr != mgrPtr)
97 		|| (winPtr->geomData != clientData))
98 	    && (winPtr->geomMgrPtr->lostContentProc != NULL)) {
99 	winPtr->geomMgrPtr->lostContentProc(winPtr->geomData, tkwin);
100     }
101 
102     winPtr->geomMgrPtr = mgrPtr;
103     winPtr->geomData = clientData;
104 }
105 
106 /*
107  *--------------------------------------------------------------
108  *
109  * Tk_GeometryRequest --
110  *
111  *	This procedure is invoked by widget code to indicate its preferences
112  *	about the size of a window it manages. In general, widget code should
113  *	call this procedure rather than Tk_ResizeWindow.
114  *
115  * Results:
116  *	None.
117  *
118  * Side effects:
119  *	The geometry manager for tkwin (if any) is invoked to handle the
120  *	request. If possible, it will reconfigure tkwin and/or other windows
121  *	to satisfy the request. The caller gets no indication of success or
122  *	failure, but it will get X events if the window size was actually
123  *	changed.
124  *
125  *--------------------------------------------------------------
126  */
127 
128 void
Tk_GeometryRequest(Tk_Window tkwin,int reqWidth,int reqHeight)129 Tk_GeometryRequest(
130     Tk_Window tkwin,		/* Window that geometry information pertains
131 				 * to. */
132     int reqWidth, int reqHeight)/* Minimum desired dimensions for window, in
133 				 * pixels. */
134 {
135     TkWindow *winPtr = (TkWindow *) tkwin;
136 
137     /*
138      * X gets very upset if a window requests a width or height of zero, so
139      * rounds requested sizes up to at least 1.
140      */
141 
142     if (reqWidth <= 0) {
143 	reqWidth = 1;
144     }
145     if (reqHeight <= 0) {
146 	reqHeight = 1;
147     }
148     if ((reqWidth == winPtr->reqWidth) && (reqHeight == winPtr->reqHeight)) {
149 	return;
150     }
151     winPtr->reqWidth = reqWidth;
152     winPtr->reqHeight = reqHeight;
153     if ((winPtr->geomMgrPtr != NULL)
154 	    && (winPtr->geomMgrPtr->requestProc != NULL)) {
155 	winPtr->geomMgrPtr->requestProc(winPtr->geomData, tkwin);
156     }
157 }
158 
159 /*
160  *----------------------------------------------------------------------
161  *
162  * Tk_SetInternalBorderEx --
163  *
164  *	Notify relevant geometry managers that a window has an internal border
165  *	of a given width and that child windows should not be placed on that
166  *	border.
167  *
168  * Results:
169  *	None.
170  *
171  * Side effects:
172  *	The border widths are recorded for the window, and all geometry
173  *	managers of all children are notified so that can re-layout, if
174  *	necessary.
175  *
176  *----------------------------------------------------------------------
177  */
178 
179 void
Tk_SetInternalBorderEx(Tk_Window tkwin,int left,int right,int top,int bottom)180 Tk_SetInternalBorderEx(
181     Tk_Window tkwin,		/* Window that will have internal border. */
182     int left, int right,	/* Width of internal border, in pixels. */
183     int top, int bottom)
184 {
185     TkWindow *winPtr = (TkWindow *) tkwin;
186     int changed = 0;
187 
188     if (left < 0) {
189 	left = 0;
190     }
191     if (left != winPtr->internalBorderLeft) {
192 	winPtr->internalBorderLeft = left;
193 	changed = 1;
194     }
195 
196     if (right < 0) {
197 	right = 0;
198     }
199     if (right != winPtr->internalBorderRight) {
200 	winPtr->internalBorderRight = right;
201 	changed = 1;
202     }
203 
204     if (top < 0) {
205 	top = 0;
206     }
207     if (top != winPtr->internalBorderTop) {
208 	winPtr->internalBorderTop = top;
209 	changed = 1;
210     }
211 
212     if (bottom < 0) {
213 	bottom = 0;
214     }
215     if (bottom != winPtr->internalBorderBottom) {
216 	winPtr->internalBorderBottom = bottom;
217 	changed = 1;
218     }
219 
220     /*
221      * All the content for which this is the container window must now be
222      * repositioned to take account of the new internal border width. To
223      * signal all the geometry managers to do this, trigger a ConfigureNotify
224      * event. This will cause geometry managers to recompute everything.
225      */
226 
227     if (changed) {
228 	TkDoConfigureNotify(winPtr);
229     }
230 }
231 
232 /*
233  *----------------------------------------------------------------------
234  *
235  * Tk_SetInternalBorder --
236  *
237  *	Notify relevant geometry managers that a window has an internal border
238  *	of a given width and that child windows should not be placed on that
239  *	border.
240  *
241  * Results:
242  *	None.
243  *
244  * Side effects:
245  *	The border width is recorded for the window, and all geometry managers
246  *	of all children are notified so that can re-layout, if necessary.
247  *
248  *----------------------------------------------------------------------
249  */
250 
251 void
Tk_SetInternalBorder(Tk_Window tkwin,int width)252 Tk_SetInternalBorder(
253     Tk_Window tkwin,		/* Window that will have internal border. */
254     int width)			/* Width of internal border, in pixels. */
255 {
256     Tk_SetInternalBorderEx(tkwin, width, width, width, width);
257 }
258 
259 /*
260  *----------------------------------------------------------------------
261  *
262  * Tk_SetMinimumRequestSize --
263  *
264  *	Notify relevant geometry managers that a window has a minimum request
265  *	size.
266  *
267  * Results:
268  *	None.
269  *
270  * Side effects:
271  *	The minimum request size is recorded for the window, and a new size is
272  *	requested for the window, if necessary.
273  *
274  *----------------------------------------------------------------------
275  */
276 
277 void
Tk_SetMinimumRequestSize(Tk_Window tkwin,int minWidth,int minHeight)278 Tk_SetMinimumRequestSize(
279     Tk_Window tkwin,		/* Window that will have internal border. */
280     int minWidth, int minHeight)/* Minimum requested size, in pixels. */
281 {
282     TkWindow *winPtr = (TkWindow *) tkwin;
283 
284     if ((winPtr->minReqWidth == minWidth) &&
285 	    (winPtr->minReqHeight == minHeight)) {
286 	return;
287     }
288 
289     winPtr->minReqWidth = minWidth;
290     winPtr->minReqHeight = minHeight;
291 
292     /*
293      * The changed min size may cause geometry managers to get a different
294      * result, so make them recompute. To signal all the geometry managers to
295      * do this, just resize the window to its current size. The
296      * ConfigureNotify event will cause geometry managers to recompute
297      * everything.
298      */
299 
300     Tk_ResizeWindow(tkwin, Tk_Width(tkwin), Tk_Height(tkwin));
301 }
302 
303 /*
304  *----------------------------------------------------------------------
305  *
306  * TkSetGeometryContainer --
307  *
308  *	Set a geometry container for this window. Only one container may own
309  *	a window at any time.
310  *
311  * Results:
312  *	A standard Tcl result.
313  *
314  * Side effects:
315  *	The geometry container is recorded for the window.
316  *
317  *----------------------------------------------------------------------
318  */
319 
320 int
TkSetGeometryContainer(Tcl_Interp * interp,Tk_Window tkwin,const char * name)321 TkSetGeometryContainer(
322     Tcl_Interp *interp,		/* Current interpreter, for error. */
323     Tk_Window tkwin,		/* Window that will have geometry container
324 				 * set. */
325     const char *name)		/* The name of the geometry manager. */
326 {
327     TkWindow *winPtr = (TkWindow *) tkwin;
328 
329     if (winPtr->geomMgrName != NULL &&
330 	    strcmp(winPtr->geomMgrName, name) == 0) {
331 	return TCL_OK;
332     }
333     if (winPtr->geomMgrName != NULL) {
334 	if (interp != NULL) {
335 	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
336 		    "cannot use geometry manager %s inside %s because"
337 		    " %s is already managing it's content windows",
338 		    name, Tk_PathName(tkwin), winPtr->geomMgrName));
339 	    Tcl_SetErrorCode(interp, "TK", "GEOMETRY", "FIGHT", NULL);
340 	}
341 	return TCL_ERROR;
342     }
343 
344     winPtr->geomMgrName = (char *)ckalloc(strlen(name) + 1);
345     strcpy(winPtr->geomMgrName, name);
346     return TCL_OK;
347 }
348 
349 /*
350  *----------------------------------------------------------------------
351  *
352  * TkFreeGeometryContainer --
353  *
354  *	Remove a geometry container for this window. Only one container may own
355  *	a window at any time.
356  *
357  * Results:
358  *	None.
359  *
360  * Side effects:
361  *	The geometry container is cleared for the window.
362  *
363  *----------------------------------------------------------------------
364  */
365 
366 void
TkFreeGeometryContainer(Tk_Window tkwin,const char * name)367 TkFreeGeometryContainer(
368     Tk_Window tkwin,		/* Window that will have geometry container
369 				 * cleared. */
370     const char *name)		/* The name of the geometry manager. */
371 {
372     TkWindow *winPtr = (TkWindow *) tkwin;
373 
374     if (winPtr->geomMgrName != NULL &&
375 	    strcmp(winPtr->geomMgrName, name) != 0) {
376 	Tcl_Panic("Trying to free %s from geometry manager %s",
377 		winPtr->geomMgrName, name);
378     }
379     if (winPtr->geomMgrName != NULL) {
380 	ckfree(winPtr->geomMgrName);
381 	winPtr->geomMgrName = NULL;
382     }
383 }
384 
385 /*
386  *----------------------------------------------------------------------
387  *
388  * Tk_MaintainGeometry --
389  *
390  *	This procedure is invoked by geometry managers to handle content whose
391  *	container's are not their parents. It translates the desired geometry for
392  *	the content into the coordinate system of the parent and respositions
393  *	the content if it isn't already at the right place. Furthermore, it sets
394  *	up event handlers so that if the container (or any of its ancestors up to
395  *	the content's parent) is mapped, unmapped, or moved, then the content will
396  *	be adjusted to match.
397  *
398  * Results:
399  *	None.
400  *
401  * Side effects:
402  *	Event handlers are created and state is allocated to keep track of
403  *	content. Note: if content was already managed for container by
404  *	Tk_MaintainGeometry, then the previous information is replaced with
405  *	the new information. The caller must eventually call
406  *	Tk_UnmaintainGeometry to eliminate the correspondence (or, the state
407  *	is automatically freed when either window is destroyed).
408  *
409  *----------------------------------------------------------------------
410  */
411 
412 void
Tk_MaintainGeometry(Tk_Window window,Tk_Window container,int x,int y,int width,int height)413 Tk_MaintainGeometry(
414     Tk_Window window,		/* Window for geometry management. */
415     Tk_Window container,		/* Container for window; must be a descendant of
416 				 * window's parent. */
417     int x, int y,		/* Desired position of window within container. */
418     int width, int height)	/* Desired dimensions for window. */
419 {
420     Tcl_HashEntry *hPtr;
421     MaintainContainer *containerPtr;
422     MaintainContent *contentPtr;
423     int isNew, map;
424     Tk_Window ancestor, parent;
425     TkDisplay *dispPtr = ((TkWindow *) container)->dispPtr;
426 
427     ((TkWindow *)window)->maintainerPtr = (TkWindow *)container;
428 
429     if (container == Tk_Parent(window)) {
430 	/*
431 	 * If the window is a direct descendant of the container, don't bother
432 	 * setting up the extra infrastructure for management, just make a
433 	 * call to Tk_MoveResizeWindow; the parent/child relationship will
434 	 * take care of the rest.
435 	 */
436 
437 	Tk_MoveResizeWindow(window, x, y, width, height);
438 
439 	/*
440 	 * Map the window if the container is already mapped; otherwise, wait
441 	 * until the container is mapped later (in which case mapping the window
442 	 * is taken care of elsewhere).
443 	 */
444 
445 	if (Tk_IsMapped(container)) {
446 	    Tk_MapWindow(window);
447 	}
448 	return;
449     }
450 
451     if (!dispPtr->geomInit) {
452 	dispPtr->geomInit = 1;
453 	Tcl_InitHashTable(&dispPtr->maintainHashTable, TCL_ONE_WORD_KEYS);
454     }
455 
456     /*
457      * See if there is already a MaintainContainer structure for the container; if
458      * not, then create one.
459      */
460 
461     parent = Tk_Parent(window);
462     hPtr = Tcl_CreateHashEntry(&dispPtr->maintainHashTable,
463 	    (char *) container, &isNew);
464     if (!isNew) {
465 	containerPtr = (MaintainContainer *)Tcl_GetHashValue(hPtr);
466     } else {
467 	containerPtr = (MaintainContainer *)ckalloc(sizeof(MaintainContainer));
468 	containerPtr->ancestor = container;
469 	containerPtr->checkScheduled = 0;
470 	containerPtr->contentPtr = NULL;
471 	Tcl_SetHashValue(hPtr, containerPtr);
472     }
473 
474     /*
475      * Create a MaintainContent structure for the window if there isn't already
476      * one.
477      */
478 
479     for (contentPtr = containerPtr->contentPtr; contentPtr != NULL;
480 	    contentPtr = contentPtr->nextPtr) {
481 	if (contentPtr->content == window) {
482 	    goto gotContent;
483 	}
484     }
485     contentPtr = (MaintainContent *)ckalloc(sizeof(MaintainContent));
486     contentPtr->content = window;
487     contentPtr->container = container;
488     contentPtr->nextPtr = containerPtr->contentPtr;
489     containerPtr->contentPtr = contentPtr;
490     Tk_CreateEventHandler(window, StructureNotifyMask, MaintainContentProc,
491 	    contentPtr);
492 
493     /*
494      * Make sure that there are event handlers registered for all the windows
495      * between container and windows's parent (including container but not window's
496      * parent). There may already be handlers for container and some of its
497      * ancestors (containerPtr->ancestor tells how many).
498      */
499 
500     for (ancestor = container; ancestor != parent;
501 	    ancestor = Tk_Parent(ancestor)) {
502 	if (ancestor == containerPtr->ancestor) {
503 	    Tk_CreateEventHandler(ancestor, StructureNotifyMask,
504 		    MaintainContainerProc, containerPtr);
505 	    containerPtr->ancestor = Tk_Parent(ancestor);
506 	}
507     }
508 
509     /*
510      * Fill in up-to-date information in the structure, then update the window
511      * if it's not currently in the right place or state.
512      */
513 
514   gotContent:
515     contentPtr->x = x;
516     contentPtr->y = y;
517     contentPtr->width = width;
518     contentPtr->height = height;
519     map = 1;
520     for (ancestor = contentPtr->container; ; ancestor = Tk_Parent(ancestor)) {
521 	if (!Tk_IsMapped(ancestor) && (ancestor != parent)) {
522 	    map = 0;
523 	}
524 	if (ancestor == parent) {
525 	    if ((x != Tk_X(contentPtr->content))
526 		    || (y != Tk_Y(contentPtr->content))
527 		    || (width != Tk_Width(contentPtr->content))
528 		    || (height != Tk_Height(contentPtr->content))) {
529 		Tk_MoveResizeWindow(contentPtr->content, x, y, width, height);
530 	    }
531 	    if (map) {
532 		Tk_MapWindow(contentPtr->content);
533 	    } else {
534 		Tk_UnmapWindow(contentPtr->content);
535 	    }
536 	    break;
537 	}
538 	x += Tk_X(ancestor) + Tk_Changes(ancestor)->border_width;
539 	y += Tk_Y(ancestor) + Tk_Changes(ancestor)->border_width;
540     }
541 }
542 
543 /*
544  *----------------------------------------------------------------------
545  *
546  * Tk_UnmaintainGeometry --
547  *
548  *	This procedure cancels a previous Tk_MaintainGeometry call, so that
549  *	the relationship between window and container is no longer maintained.
550  *
551  * Results:
552  *	None.
553  *
554  * Side effects:
555  *	The window is unmapped and state is released, so that window won't track
556  *	container any more. If we weren't previously managing window relative to
557  *	container, then this procedure has no effect.
558  *
559  *----------------------------------------------------------------------
560  */
561 
562 void
Tk_UnmaintainGeometry(Tk_Window window,Tk_Window container)563 Tk_UnmaintainGeometry(
564     Tk_Window window,		/* WIndow for geometry management. */
565     Tk_Window container)		/* Container for window; must be a descendant of
566 				 * window's parent. */
567 {
568     Tcl_HashEntry *hPtr;
569     MaintainContainer *containerPtr;
570     MaintainContent *contentPtr, *prevPtr;
571     Tk_Window ancestor;
572     TkDisplay *dispPtr = ((TkWindow *) window)->dispPtr;
573 
574     ((TkWindow *)window)->maintainerPtr = NULL;
575 
576     if (container == Tk_Parent(window)) {
577 	/*
578 	 * If the window is a direct descendant of the container,
579 	 * Tk_MaintainGeometry will not have set up any of the extra
580 	 * infrastructure. Don't even bother to look for it, just return.
581 	 */
582 	return;
583     }
584 
585     if (!dispPtr->geomInit) {
586 	dispPtr->geomInit = 1;
587 	Tcl_InitHashTable(&dispPtr->maintainHashTable, TCL_ONE_WORD_KEYS);
588     }
589 
590     if (!(((TkWindow *) window)->flags & TK_ALREADY_DEAD)) {
591 	Tk_UnmapWindow(window);
592     }
593     hPtr = Tcl_FindHashEntry(&dispPtr->maintainHashTable, container);
594     if (hPtr == NULL) {
595 	return;
596     }
597     containerPtr = (MaintainContainer *)Tcl_GetHashValue(hPtr);
598     contentPtr = containerPtr->contentPtr;
599     if (contentPtr->content == window) {
600 	containerPtr->contentPtr = contentPtr->nextPtr;
601     } else {
602 	for (prevPtr = contentPtr, contentPtr = contentPtr->nextPtr; ;
603 		prevPtr = contentPtr, contentPtr = contentPtr->nextPtr) {
604 	    if (contentPtr == NULL) {
605 		return;
606 	    }
607 	    if (contentPtr->content == window) {
608 		prevPtr->nextPtr = contentPtr->nextPtr;
609 		break;
610 	    }
611 	}
612     }
613     Tk_DeleteEventHandler(contentPtr->content, StructureNotifyMask,
614 	    MaintainContentProc, contentPtr);
615     ckfree(contentPtr);
616     if (containerPtr->contentPtr == NULL) {
617 	if (containerPtr->ancestor != NULL) {
618 	    for (ancestor = container; ; ancestor = Tk_Parent(ancestor)) {
619 		Tk_DeleteEventHandler(ancestor, StructureNotifyMask,
620 			MaintainContainerProc, containerPtr);
621 		if (ancestor == containerPtr->ancestor) {
622 		    break;
623 		}
624 	    }
625 	}
626 	if (containerPtr->checkScheduled) {
627 	    Tcl_CancelIdleCall(MaintainCheckProc, containerPtr);
628 	}
629 	Tcl_DeleteHashEntry(hPtr);
630 	ckfree(containerPtr);
631     }
632 }
633 
634 /*
635  *----------------------------------------------------------------------
636  *
637  * MaintainContainerProc --
638  *
639  *	This procedure is invoked by the Tk event dispatcher in response to
640  *	StructureNotify events on the container or one of its ancestors, on
641  *	behalf of Tk_MaintainGeometry.
642  *
643  * Results:
644  *	None.
645  *
646  * Side effects:
647  *	It schedules a call to MaintainCheckProc, which will eventually caused
648  *	the postions and mapped states to be recalculated for all the
649  *	maintained windows of the container. Or, if the container window is being
650  *	deleted then state is cleaned up.
651  *
652  *----------------------------------------------------------------------
653  */
654 
655 static void
MaintainContainerProc(ClientData clientData,XEvent * eventPtr)656 MaintainContainerProc(
657     ClientData clientData,	/* Pointer to MaintainContainer structure for the
658 				 * container window. */
659     XEvent *eventPtr)		/* Describes what just happened. */
660 {
661     MaintainContainer *containerPtr = (MaintainContainer *)clientData;
662     MaintainContent *contentPtr;
663     int done;
664 
665     if ((eventPtr->type == ConfigureNotify)
666 	    || (eventPtr->type == MapNotify)
667 	    || (eventPtr->type == UnmapNotify)) {
668 	if (!containerPtr->checkScheduled) {
669 	    containerPtr->checkScheduled = 1;
670 	    Tcl_DoWhenIdle(MaintainCheckProc, containerPtr);
671 	}
672     } else if (eventPtr->type == DestroyNotify) {
673 	/*
674 	 * Delete all of the state associated with this container, but be careful
675 	 * not to use containerPtr after the last window is deleted, since its
676 	 * memory will have been freed.
677 	 */
678 
679 	done = 0;
680 	do {
681 	    contentPtr = containerPtr->contentPtr;
682 	    if (contentPtr->nextPtr == NULL) {
683 		done = 1;
684 	    }
685 	    Tk_UnmaintainGeometry(contentPtr->content, contentPtr->container);
686 	} while (!done);
687     }
688 }
689 
690 /*
691  *----------------------------------------------------------------------
692  *
693  * MaintainContentProc --
694  *
695  *	This procedure is invoked by the Tk event dispatcher in response to
696  *	StructureNotify events on a window being managed by
697  *	Tk_MaintainGeometry.
698  *
699  * Results:
700  *	None.
701  *
702  * Side effects:
703  *	If the event is a DestroyNotify event then the Maintain state and
704  *	event handlers for this window are deleted.
705  *
706  *----------------------------------------------------------------------
707  */
708 
709 static void
MaintainContentProc(ClientData clientData,XEvent * eventPtr)710 MaintainContentProc(
711     ClientData clientData,	/* Pointer to MaintainContent structure for
712 				 * container-window pair. */
713     XEvent *eventPtr)		/* Describes what just happened. */
714 {
715     MaintainContent *contentPtr = (MaintainContent *)clientData;
716 
717     if (eventPtr->type == DestroyNotify) {
718 	Tk_UnmaintainGeometry(contentPtr->content, contentPtr->container);
719     }
720 }
721 
722 /*
723  *----------------------------------------------------------------------
724  *
725  * MaintainCheckProc --
726  *
727  *	This procedure is invoked by the Tk event dispatcher as an idle
728  *	handler, when a container or one of its ancestors has been reconfigured,
729  *	mapped, or unmapped. Its job is to scan all of the windows for the
730  *	container and reposition them, map them, or unmap them as needed to
731  *	maintain their geometry relative to the container.
732  *
733  * Results:
734  *	None.
735  *
736  * Side effects:
737  *	Windows can get repositioned, mapped, or unmapped.
738  *
739  *----------------------------------------------------------------------
740  */
741 
742 static void
MaintainCheckProc(ClientData clientData)743 MaintainCheckProc(
744     ClientData clientData)	/* Pointer to MaintainContainer structure for the
745 				 * container window. */
746 {
747     MaintainContainer *containerPtr = (MaintainContainer *)clientData;
748     MaintainContent *contentPtr;
749     Tk_Window ancestor, parent;
750     int x, y, map;
751 
752     containerPtr->checkScheduled = 0;
753     for (contentPtr = containerPtr->contentPtr; contentPtr != NULL;
754 	    contentPtr = contentPtr->nextPtr) {
755 	parent = Tk_Parent(contentPtr->content);
756 	x = contentPtr->x;
757 	y = contentPtr->y;
758 	map = 1;
759 	for (ancestor = contentPtr->container; ; ancestor = Tk_Parent(ancestor)) {
760 	    if (!Tk_IsMapped(ancestor) && (ancestor != parent)) {
761 		map = 0;
762 	    }
763 	    if (ancestor == parent) {
764 		if ((x != Tk_X(contentPtr->content))
765 			|| (y != Tk_Y(contentPtr->content))) {
766 		    Tk_MoveWindow(contentPtr->content, x, y);
767 		}
768 		if (map) {
769 		    Tk_MapWindow(contentPtr->content);
770 		} else {
771 		    Tk_UnmapWindow(contentPtr->content);
772 		}
773 		break;
774 	    }
775 	    x += Tk_X(ancestor) + Tk_Changes(ancestor)->border_width;
776 	    y += Tk_Y(ancestor) + Tk_Changes(ancestor)->border_width;
777 	}
778     }
779 }
780 
781 /*
782  * Local Variables:
783  * mode: c
784  * c-basic-offset: 4
785  * fill-column: 78
786  * End:
787  */
788