2 * Copyright (C) 2007-2010 Openismus GmbH
5 * Mathias Hasselmann <mathias@openismus.com>
6 * Tristan Van Berkom <tristan.van.berkom@gmail.com>
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
26 #include "gtksizerequest.h"
30 #include "gtkprivate.h"
31 #include "gtksizegroup-private.h"
32 #include "gtkwidgetprivate.h"
35 #ifndef G_DISABLE_CHECKS
36 static GQuark recursion_check_quark = 0;
37 #endif /* G_DISABLE_CHECKS */
40 push_recursion_check (GtkWidget *widget,
41 GtkSizeGroupMode orientation,
44 #ifndef G_DISABLE_CHECKS
45 const char *previous_method;
48 if (recursion_check_quark == 0)
49 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
51 previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
53 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
55 method = for_size < 0 ? "get_width" : "get_width_for_height";
59 method = for_size < 0 ? "get_height" : "get_height_for_width";
62 if (previous_method != NULL)
64 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
65 " GtkWidget ::%s implementation. "
66 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
67 "directly rather than using gtk_widget_%s",
68 G_OBJECT_TYPE_NAME (widget), widget,
69 method, previous_method,
73 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
74 #endif /* G_DISABLE_CHECKS */
78 pop_recursion_check (GtkWidget *widget,
79 GtkSizeGroupMode orientation)
81 #ifndef G_DISABLE_CHECKS
82 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
88 clear_cache (SizeRequestCache *cache,
89 GtkSizeGroupMode orientation)
94 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
96 sizes = cache->widths;
99 cache->cached_widths = 0;
100 cache->last_cached_width = 0;
101 cache->cached_base_width = FALSE;
105 sizes = cache->heights;
107 cache->heights = NULL;
108 cache->cached_heights = 0;
109 cache->last_cached_height = 0;
110 cache->cached_base_height = FALSE;
115 for (i = 0; i < GTK_SIZE_REQUEST_CACHED_SIZES && sizes[i] != NULL; i++)
116 g_slice_free (SizeRequest, sizes[i]);
118 g_slice_free1 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES, sizes);
123 _gtk_widget_free_cached_sizes (GtkWidget *widget)
125 SizeRequestCache *cache;
127 cache = _gtk_widget_peek_request_cache (widget);
129 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
130 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
133 /* This function checks if 'request_needed' flag is present
134 * and resets the cache state if a request is needed for
135 * a given orientation.
137 static SizeRequestCache *
138 init_cache (GtkWidget *widget)
140 SizeRequestCache *cache;
142 cache = _gtk_widget_peek_request_cache (widget);
144 if (_gtk_widget_get_width_request_needed (widget))
145 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
146 else if (_gtk_widget_get_height_request_needed (widget))
147 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
152 /* looks for a cached size request for this for_size. If not
153 * found, returns the oldest entry so it can be overwritten
155 * Note that this caching code was originally derived from
156 * the Clutter toolkit but has evolved for other GTK+ requirements.
159 get_cached_size (GtkWidget *widget,
160 GtkSizeGroupMode orientation,
164 SizeRequestCache *cache;
165 SizeRequest **cached_sizes;
168 cache = init_cache (widget);
172 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
174 *result = &cache->cached_width;
175 return cache->cached_base_width;
179 *result = &cache->cached_height;
180 return cache->cached_base_height;
184 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
186 cached_sizes = cache->widths;
187 n_sizes = cache->cached_widths;
191 cached_sizes = cache->heights;
192 n_sizes = cache->cached_heights;
195 /* Search for an already cached size */
196 for (i = 0; i < n_sizes; i++)
198 if (cached_sizes[i]->lower_for_size <= for_size &&
199 cached_sizes[i]->upper_for_size >= for_size)
201 *result = &cached_sizes[i]->cached_size;
210 commit_cached_size (GtkWidget *widget,
211 GtkSizeGroupMode orientation,
216 SizeRequestCache *cache;
217 SizeRequest **cached_sizes;
220 cache = _gtk_widget_peek_request_cache (widget);
222 /* First handle caching of the base requests */
225 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
227 cache->cached_width.minimum_size = minimum_size;
228 cache->cached_width.natural_size = natural_size;
229 cache->cached_base_width = TRUE;
233 cache->cached_height.minimum_size = minimum_size;
234 cache->cached_height.natural_size = natural_size;
235 cache->cached_base_height = TRUE;
240 /* Check if the minimum_size and natural_size is already
241 * in the cache and if this result can be used to extend
244 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
246 cached_sizes = cache->widths;
247 n_sizes = cache->cached_widths;
251 cached_sizes = cache->heights;
252 n_sizes = cache->cached_heights;
255 for (i = 0; i < n_sizes; i++)
257 if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
258 cached_sizes[i]->cached_size.natural_size == natural_size)
260 cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
261 cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
266 /* If not found, pull a new size from the cache, the returned size cache
267 * will immediately be used to cache the new computed size so we go ahead
268 * and increment the last_cached_width/height right away */
269 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
271 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
273 cache->cached_widths++;
274 cache->last_cached_width = cache->cached_widths - 1;
278 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
279 cache->last_cached_width = 0;
283 cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
285 if (!cache->widths[cache->last_cached_width])
286 cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
288 cache->widths[cache->last_cached_width]->lower_for_size = for_size;
289 cache->widths[cache->last_cached_width]->upper_for_size = for_size;
290 cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
291 cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
293 else /* GTK_SIZE_GROUP_VERTICAL */
295 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
297 cache->cached_heights++;
298 cache->last_cached_height = cache->cached_heights - 1;
302 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
303 cache->last_cached_height = 0;
307 cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
309 if (!cache->heights[cache->last_cached_height])
310 cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
312 cache->heights[cache->last_cached_height]->lower_for_size = for_size;
313 cache->heights[cache->last_cached_height]->upper_for_size = for_size;
314 cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
315 cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
319 /* This is the main function that checks for a cached size and
320 * possibly queries the widget class to compute the size if it's
321 * not cached. If the for_size here is -1, then get_preferred_width()
322 * or get_preferred_height() will be used.
325 compute_size_for_orientation (GtkWidget *widget,
326 GtkSizeGroupMode orientation,
331 CachedSize *cached_size;
332 gboolean found_in_cache = FALSE;
336 found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
340 gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
342 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
346 push_recursion_check (widget, orientation, for_size);
347 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
348 pop_recursion_check (widget, orientation);
352 gint ignored_position = 0;
356 /* Pull the base natural height from the cache as it's needed to adjust
357 * the proposed 'for_size' */
358 gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
360 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
361 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
362 GTK_ORIENTATION_VERTICAL,
368 push_recursion_check (widget, orientation, for_size);
369 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget,
370 MAX (adjusted_for_size, minimum_height),
371 &min_size, &nat_size);
372 pop_recursion_check (widget, orientation);
379 push_recursion_check (widget, orientation, for_size);
380 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
381 pop_recursion_check (widget, orientation);
385 gint ignored_position = 0;
389 /* Pull the base natural width from the cache as it's needed to adjust
390 * the proposed 'for_size' */
391 gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
393 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
394 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
395 GTK_ORIENTATION_HORIZONTAL,
401 push_recursion_check (widget, orientation, for_size);
402 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget,
403 MAX (adjusted_for_size, minimum_width),
404 &min_size, &nat_size);
405 pop_recursion_check (widget, orientation);
409 if (min_size > nat_size)
411 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
412 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
415 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
416 _gtk_widget_set_width_request_needed (widget, FALSE);
418 _gtk_widget_set_height_request_needed (widget, FALSE);
420 adjusted_min = min_size;
421 adjusted_natural = nat_size;
422 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
423 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
424 GTK_ORIENTATION_HORIZONTAL :
425 GTK_ORIENTATION_VERTICAL,
429 if (adjusted_min < min_size ||
430 adjusted_natural < nat_size)
432 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
433 G_OBJECT_TYPE_NAME (widget), widget,
434 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
435 adjusted_min, adjusted_natural,
437 /* don't use the adjustment */
439 else if (adjusted_min > adjusted_natural)
441 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
442 G_OBJECT_TYPE_NAME (widget), widget,
443 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
444 adjusted_min, adjusted_natural,
446 /* don't use the adjustment */
450 /* adjustment looks good */
451 min_size = adjusted_min;
452 nat_size = adjusted_natural;
455 /* Update size-groups with our request and update our cached requests
456 * with the size-group values in a single pass.
458 _gtk_size_group_bump_requisition (widget,
463 commit_cached_size (widget, orientation, for_size, min_size, nat_size);
467 min_size = cached_size->minimum_size;
468 nat_size = cached_size->natural_size;
472 *minimum_size = min_size;
475 *natural_size = nat_size;
477 g_assert (min_size <= nat_size);
479 GTK_NOTE (SIZE_REQUEST,
480 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
481 widget, G_OBJECT_TYPE_NAME (widget),
482 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
483 "width for height" : "height for width" ,
484 for_size, min_size, nat_size,
485 found_in_cache ? "yes" : "no"));
490 * gtk_widget_get_request_mode:
491 * @widget: a #GtkWidget instance
493 * Gets whether the widget prefers a height-for-width layout
494 * or a width-for-height layout.
496 * <note><para>#GtkBin widgets generally propagate the preference of
497 * their child, container widgets need to request something either in
498 * context of their children or in context of their allocation
499 * capabilities.</para></note>
501 * Returns: The #GtkSizeRequestMode preferred by @widget.
506 gtk_widget_get_request_mode (GtkWidget *widget)
508 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH);
510 return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
514 * gtk_widget_get_preferred_width:
515 * @widget: a #GtkWidget instance
516 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
517 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
519 * Retrieves a widget's initial minimum and natural width.
521 * <note><para>This call is specific to height-for-width
522 * requests.</para></note>
524 * The returned request will be modified by the
525 * GtkWidgetClass::adjust_size_request virtual method and by any
526 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
527 * is the one that should be used for layout, not necessarily the one
528 * returned by the widget itself.
533 gtk_widget_get_preferred_width (GtkWidget *widget,
537 g_return_if_fail (GTK_IS_WIDGET (widget));
538 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
540 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
541 -1, minimum_width, natural_width);
546 * gtk_widget_get_preferred_height:
547 * @widget: a #GtkWidget instance
548 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
549 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
551 * Retrieves a widget's initial minimum and natural height.
553 * <note><para>This call is specific to width-for-height requests.</para></note>
555 * The returned request will be modified by the
556 * GtkWidgetClass::adjust_size_request virtual method and by any
557 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
558 * is the one that should be used for layout, not necessarily the one
559 * returned by the widget itself.
564 gtk_widget_get_preferred_height (GtkWidget *widget,
565 gint *minimum_height,
566 gint *natural_height)
568 g_return_if_fail (GTK_IS_WIDGET (widget));
569 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
571 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
572 -1, minimum_height, natural_height);
578 * gtk_widget_get_preferred_width_for_height:
579 * @widget: a #GtkWidget instance
580 * @height: the height which is available for allocation
581 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
582 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
584 * Retrieves a widget's minimum and natural width if it would be given
585 * the specified @height.
587 * The returned request will be modified by the
588 * GtkWidgetClass::adjust_size_request virtual method and by any
589 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
590 * is the one that should be used for layout, not necessarily the one
591 * returned by the widget itself.
596 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
601 g_return_if_fail (GTK_IS_WIDGET (widget));
602 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
603 g_return_if_fail (height >= 0);
605 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
606 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
607 -1, minimum_width, natural_width);
609 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
610 height, minimum_width, natural_width);
614 * gtk_widget_get_preferred_height_for_width:
615 * @widget: a #GtkWidget instance
616 * @width: the width which is available for allocation
617 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
618 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
620 * Retrieves a widget's minimum and natural height if it would be given
621 * the specified @width.
623 * The returned request will be modified by the
624 * GtkWidgetClass::adjust_size_request virtual method and by any
625 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
626 * is the one that should be used for layout, not necessarily the one
627 * returned by the widget itself.
632 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
634 gint *minimum_height,
635 gint *natural_height)
637 g_return_if_fail (GTK_IS_WIDGET (widget));
638 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
639 g_return_if_fail (width >= 0);
641 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
642 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
643 -1, minimum_height, natural_height);
645 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
646 width, minimum_height, natural_height);
650 * gtk_widget_get_preferred_size:
651 * @widget: a #GtkWidget instance
652 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
653 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
655 * Retrieves the minimum and natural size of a widget, taking
656 * into account the widget's preference for height-for-width management.
658 * This is used to retrieve a suitable size by container widgets which do
659 * not impose any restrictions on the child placement. It can be used
660 * to deduce toplevel window and menu sizes as well as child widgets in
661 * free-form containers such as GtkLayout.
663 * <note><para>Handle with care. Note that the natural height of a height-for-width
664 * widget will generally be a smaller size than the minimum height, since the required
665 * height for the natural width is generally smaller than the required height for
666 * the minimum width.</para></note>
671 gtk_widget_get_preferred_size (GtkWidget *widget,
672 GtkRequisition *minimum_size,
673 GtkRequisition *natural_size)
675 gint min_width, nat_width;
676 gint min_height, nat_height;
678 g_return_if_fail (GTK_IS_WIDGET (widget));
680 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
682 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
686 minimum_size->width = min_width;
687 gtk_widget_get_preferred_height_for_width (widget, min_width,
688 &minimum_size->height, NULL);
693 natural_size->width = nat_width;
694 gtk_widget_get_preferred_height_for_width (widget, nat_width,
695 NULL, &natural_size->height);
698 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
700 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
704 minimum_size->height = min_height;
705 gtk_widget_get_preferred_width_for_height (widget, min_height,
706 &minimum_size->width, NULL);
711 natural_size->height = nat_height;
712 gtk_widget_get_preferred_width_for_height (widget, nat_height,
713 NULL, &natural_size->width);
720 compare_gap (gconstpointer p1,
724 GtkRequestedSize *sizes = data;
725 const guint *c1 = p1;
726 const guint *c2 = p2;
728 const gint d1 = MAX (sizes[*c1].natural_size -
729 sizes[*c1].minimum_size,
731 const gint d2 = MAX (sizes[*c2].natural_size -
732 sizes[*c2].minimum_size,
735 gint delta = (d2 - d1);
744 * gtk_distribute_natural_allocation:
745 * @extra_space: Extra space to redistribute among children after subtracting
746 * minimum sizes and any child padding from the overall allocation
747 * @n_requested_sizes: Number of requests to fit into the allocation
748 * @sizes: An array of structs with a client pointer and a minimum/natural size
749 * in the orientation of the allocation.
751 * Distributes @extra_space to child @sizes by bringing smaller
752 * children up to natural size first.
754 * The remaining space will be added to the @minimum_size member of the
755 * GtkRequestedSize struct. If all sizes reach their natural size then
756 * the remaining space is returned.
758 * Returns: The remainder of @extra_space after redistributing space
762 gtk_distribute_natural_allocation (gint extra_space,
763 guint n_requested_sizes,
764 GtkRequestedSize *sizes)
769 g_return_val_if_fail (extra_space >= 0, 0);
771 spreading = g_newa (guint, n_requested_sizes);
773 for (i = 0; i < n_requested_sizes; i++)
776 /* Distribute the container's extra space c_gap. We want to assign
777 * this space such that the sum of extra space assigned to children
778 * (c^i_gap) is equal to c_cap. The case that there's not enough
779 * space for all children to take their natural size needs some
780 * attention. The goals we want to achieve are:
782 * a) Maximize number of children taking their natural size.
783 * b) The allocated size of children should be a continuous
784 * function of c_gap. That is, increasing the container size by
785 * one pixel should never make drastic changes in the distribution.
786 * c) If child i takes its natural size and child j doesn't,
787 * child j should have received at least as much gap as child i.
789 * The following code distributes the additional space by following
793 /* Sort descending by gap and position. */
794 g_qsort_with_data (spreading,
795 n_requested_sizes, sizeof (guint),
798 /* Distribute available space.
799 * This master piece of a loop was conceived by Behdad Esfahbod.
801 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
803 /* Divide remaining space by number of remaining children.
804 * Sort order and reducing remaining space by assigned space
805 * ensures that space is distributed equally.
807 gint glue = (extra_space + i) / (i + 1);
808 gint gap = sizes[(spreading[i])].natural_size
809 - sizes[(spreading[i])].minimum_size;
811 gint extra = MIN (glue, gap);
813 sizes[spreading[i]].minimum_size += extra;
815 extra_space -= extra;