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"
33 #include "deprecated/gtkstyle.h"
36 #ifndef G_DISABLE_CHECKS
37 static GQuark recursion_check_quark = 0;
38 #endif /* G_DISABLE_CHECKS */
41 push_recursion_check (GtkWidget *widget,
42 GtkSizeGroupMode orientation,
45 #ifndef G_DISABLE_CHECKS
46 const char *previous_method;
49 if (recursion_check_quark == 0)
50 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
52 previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
54 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
56 method = for_size < 0 ? "get_width" : "get_width_for_height";
60 method = for_size < 0 ? "get_height" : "get_height_for_width";
63 if (previous_method != NULL)
65 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
66 " GtkWidget ::%s implementation. "
67 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
68 "directly rather than using gtk_widget_%s",
69 G_OBJECT_TYPE_NAME (widget), widget,
70 method, previous_method,
74 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
75 #endif /* G_DISABLE_CHECKS */
79 pop_recursion_check (GtkWidget *widget,
80 GtkSizeGroupMode orientation)
82 #ifndef G_DISABLE_CHECKS
83 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
89 clear_cache (SizeRequestCache *cache,
90 GtkSizeGroupMode orientation)
95 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
97 sizes = cache->widths;
100 cache->cached_widths = 0;
101 cache->last_cached_width = 0;
102 cache->cached_base_width = FALSE;
106 sizes = cache->heights;
108 cache->heights = NULL;
109 cache->cached_heights = 0;
110 cache->last_cached_height = 0;
111 cache->cached_base_height = FALSE;
116 for (i = 0; i < GTK_SIZE_REQUEST_CACHED_SIZES && sizes[i] != NULL; i++)
117 g_slice_free (SizeRequest, sizes[i]);
119 g_slice_free1 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES, sizes);
124 _gtk_widget_free_cached_sizes (GtkWidget *widget)
126 SizeRequestCache *cache;
128 cache = _gtk_widget_peek_request_cache (widget);
130 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
131 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
134 /* This function checks if 'request_needed' flag is present
135 * and resets the cache state if a request is needed for
136 * a given orientation.
138 static SizeRequestCache *
139 init_cache (GtkWidget *widget)
141 SizeRequestCache *cache;
143 cache = _gtk_widget_peek_request_cache (widget);
145 if (_gtk_widget_get_width_request_needed (widget))
146 clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
148 if (_gtk_widget_get_height_request_needed (widget))
149 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
154 /* looks for a cached size request for this for_size. If not
155 * found, returns the oldest entry so it can be overwritten
157 * Note that this caching code was originally derived from
158 * the Clutter toolkit but has evolved for other GTK+ requirements.
161 get_cached_size (GtkWidget *widget,
162 GtkSizeGroupMode orientation,
166 SizeRequestCache *cache;
167 SizeRequest **cached_sizes;
170 cache = init_cache (widget);
174 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
176 *result = &cache->cached_width;
177 return cache->cached_base_width;
181 *result = &cache->cached_height;
182 return cache->cached_base_height;
186 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
188 cached_sizes = cache->widths;
189 n_sizes = cache->cached_widths;
193 cached_sizes = cache->heights;
194 n_sizes = cache->cached_heights;
197 /* Search for an already cached size */
198 for (i = 0; i < n_sizes; i++)
200 if (cached_sizes[i]->lower_for_size <= for_size &&
201 cached_sizes[i]->upper_for_size >= for_size)
203 *result = &cached_sizes[i]->cached_size;
212 commit_cached_size (GtkWidget *widget,
213 GtkSizeGroupMode orientation,
218 SizeRequestCache *cache;
219 SizeRequest **cached_sizes;
222 cache = _gtk_widget_peek_request_cache (widget);
224 /* First handle caching of the base requests */
227 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
229 cache->cached_width.minimum_size = minimum_size;
230 cache->cached_width.natural_size = natural_size;
231 cache->cached_base_width = TRUE;
235 cache->cached_height.minimum_size = minimum_size;
236 cache->cached_height.natural_size = natural_size;
237 cache->cached_base_height = TRUE;
242 /* Check if the minimum_size and natural_size is already
243 * in the cache and if this result can be used to extend
246 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
248 cached_sizes = cache->widths;
249 n_sizes = cache->cached_widths;
253 cached_sizes = cache->heights;
254 n_sizes = cache->cached_heights;
257 for (i = 0; i < n_sizes; i++)
259 if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
260 cached_sizes[i]->cached_size.natural_size == natural_size)
262 cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
263 cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
268 /* If not found, pull a new size from the cache, the returned size cache
269 * will immediately be used to cache the new computed size so we go ahead
270 * and increment the last_cached_width/height right away */
271 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
273 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
275 cache->cached_widths++;
276 cache->last_cached_width = cache->cached_widths - 1;
280 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
281 cache->last_cached_width = 0;
285 cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
287 if (!cache->widths[cache->last_cached_width])
288 cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
290 cache->widths[cache->last_cached_width]->lower_for_size = for_size;
291 cache->widths[cache->last_cached_width]->upper_for_size = for_size;
292 cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
293 cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
295 else /* GTK_SIZE_GROUP_VERTICAL */
297 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
299 cache->cached_heights++;
300 cache->last_cached_height = cache->cached_heights - 1;
304 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
305 cache->last_cached_height = 0;
309 cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
311 if (!cache->heights[cache->last_cached_height])
312 cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
314 cache->heights[cache->last_cached_height]->lower_for_size = for_size;
315 cache->heights[cache->last_cached_height]->upper_for_size = for_size;
316 cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
317 cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
321 /* This is the main function that checks for a cached size and
322 * possibly queries the widget class to compute the size if it's
323 * not cached. If the for_size here is -1, then get_preferred_width()
324 * or get_preferred_height() will be used.
327 compute_size_for_orientation (GtkWidget *widget,
328 GtkSizeGroupMode orientation,
333 CachedSize *cached_size;
334 gboolean found_in_cache = FALSE;
338 found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
342 gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
344 gtk_widget_ensure_style (widget);
346 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
350 push_recursion_check (widget, orientation, for_size);
351 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
352 pop_recursion_check (widget, orientation);
356 gint ignored_position = 0;
360 /* Pull the base natural height from the cache as it's needed to adjust
361 * the proposed 'for_size' */
362 gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
364 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
365 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
366 GTK_ORIENTATION_VERTICAL,
372 push_recursion_check (widget, orientation, for_size);
373 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget,
374 MAX (adjusted_for_size, minimum_height),
375 &min_size, &nat_size);
376 pop_recursion_check (widget, orientation);
383 push_recursion_check (widget, orientation, for_size);
384 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
385 pop_recursion_check (widget, orientation);
389 gint ignored_position = 0;
393 /* Pull the base natural width from the cache as it's needed to adjust
394 * the proposed 'for_size' */
395 gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
397 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
398 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
399 GTK_ORIENTATION_HORIZONTAL,
405 push_recursion_check (widget, orientation, for_size);
406 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget,
407 MAX (adjusted_for_size, minimum_width),
408 &min_size, &nat_size);
409 pop_recursion_check (widget, orientation);
413 if (min_size > nat_size)
415 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
416 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
419 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
420 _gtk_widget_set_width_request_needed (widget, FALSE);
422 _gtk_widget_set_height_request_needed (widget, FALSE);
424 adjusted_min = min_size;
425 adjusted_natural = nat_size;
426 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
427 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
428 GTK_ORIENTATION_HORIZONTAL :
429 GTK_ORIENTATION_VERTICAL,
433 if (adjusted_min < min_size ||
434 adjusted_natural < nat_size)
436 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
437 G_OBJECT_TYPE_NAME (widget), widget,
438 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
439 adjusted_min, adjusted_natural,
441 /* don't use the adjustment */
443 else if (adjusted_min > adjusted_natural)
445 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
446 G_OBJECT_TYPE_NAME (widget), widget,
447 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
448 adjusted_min, adjusted_natural,
450 /* don't use the adjustment */
454 /* adjustment looks good */
455 min_size = adjusted_min;
456 nat_size = adjusted_natural;
459 /* Update size-groups with our request and update our cached requests
460 * with the size-group values in a single pass.
462 _gtk_size_group_bump_requisition (widget,
467 commit_cached_size (widget, orientation, for_size, min_size, nat_size);
471 min_size = cached_size->minimum_size;
472 nat_size = cached_size->natural_size;
476 *minimum_size = min_size;
479 *natural_size = nat_size;
481 g_assert (min_size <= nat_size);
483 GTK_NOTE (SIZE_REQUEST,
484 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
485 widget, G_OBJECT_TYPE_NAME (widget),
486 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
487 "width for height" : "height for width" ,
488 for_size, min_size, nat_size,
489 found_in_cache ? "yes" : "no"));
494 * gtk_widget_get_request_mode:
495 * @widget: a #GtkWidget instance
497 * Gets whether the widget prefers a height-for-width layout
498 * or a width-for-height layout.
500 * <note><para>#GtkBin widgets generally propagate the preference of
501 * their child, container widgets need to request something either in
502 * context of their children or in context of their allocation
503 * capabilities.</para></note>
505 * Returns: The #GtkSizeRequestMode preferred by @widget.
510 gtk_widget_get_request_mode (GtkWidget *widget)
512 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_CONSTANT_SIZE);
514 return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
518 * gtk_widget_get_preferred_width:
519 * @widget: a #GtkWidget instance
520 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
521 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
523 * Retrieves a widget's initial minimum and natural width.
525 * <note><para>This call is specific to height-for-width
526 * requests.</para></note>
528 * The returned request will be modified by the
529 * GtkWidgetClass::adjust_size_request virtual method and by any
530 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
531 * is the one that should be used for layout, not necessarily the one
532 * returned by the widget itself.
537 gtk_widget_get_preferred_width (GtkWidget *widget,
541 g_return_if_fail (GTK_IS_WIDGET (widget));
542 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
544 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
545 -1, minimum_width, natural_width);
550 * gtk_widget_get_preferred_height:
551 * @widget: a #GtkWidget instance
552 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
553 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
555 * Retrieves a widget's initial minimum and natural height.
557 * <note><para>This call is specific to width-for-height requests.</para></note>
559 * The returned request will be modified by the
560 * GtkWidgetClass::adjust_size_request virtual method and by any
561 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
562 * is the one that should be used for layout, not necessarily the one
563 * returned by the widget itself.
568 gtk_widget_get_preferred_height (GtkWidget *widget,
569 gint *minimum_height,
570 gint *natural_height)
572 g_return_if_fail (GTK_IS_WIDGET (widget));
573 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
575 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
576 -1, minimum_height, natural_height);
582 * gtk_widget_get_preferred_width_for_height:
583 * @widget: a #GtkWidget instance
584 * @height: the height which is available for allocation
585 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
586 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
588 * Retrieves a widget's minimum and natural width if it would be given
589 * the specified @height.
591 * The returned request will be modified by the
592 * GtkWidgetClass::adjust_size_request virtual method and by any
593 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
594 * is the one that should be used for layout, not necessarily the one
595 * returned by the widget itself.
600 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
605 g_return_if_fail (GTK_IS_WIDGET (widget));
606 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
607 g_return_if_fail (height >= 0);
609 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
610 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
611 -1, minimum_width, natural_width);
613 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
614 height, minimum_width, natural_width);
618 * gtk_widget_get_preferred_height_for_width:
619 * @widget: a #GtkWidget instance
620 * @width: the width which is available for allocation
621 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
622 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
624 * Retrieves a widget's minimum and natural height if it would be given
625 * the specified @width.
627 * The returned request will be modified by the
628 * GtkWidgetClass::adjust_size_request virtual method and by any
629 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
630 * is the one that should be used for layout, not necessarily the one
631 * returned by the widget itself.
636 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
638 gint *minimum_height,
639 gint *natural_height)
641 g_return_if_fail (GTK_IS_WIDGET (widget));
642 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
643 g_return_if_fail (width >= 0);
645 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
646 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
647 -1, minimum_height, natural_height);
649 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
650 width, minimum_height, natural_height);
654 * gtk_widget_get_preferred_size:
655 * @widget: a #GtkWidget instance
656 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
657 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
659 * Retrieves the minimum and natural size of a widget, taking
660 * into account the widget's preference for height-for-width management.
662 * This is used to retrieve a suitable size by container widgets which do
663 * not impose any restrictions on the child placement. It can be used
664 * to deduce toplevel window and menu sizes as well as child widgets in
665 * free-form containers such as GtkLayout.
667 * <note><para>Handle with care. Note that the natural height of a height-for-width
668 * widget will generally be a smaller size than the minimum height, since the required
669 * height for the natural width is generally smaller than the required height for
670 * the minimum width.</para></note>
675 gtk_widget_get_preferred_size (GtkWidget *widget,
676 GtkRequisition *minimum_size,
677 GtkRequisition *natural_size)
679 gint min_width, nat_width;
680 gint min_height, nat_height;
682 g_return_if_fail (GTK_IS_WIDGET (widget));
684 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
686 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
690 minimum_size->width = min_width;
691 gtk_widget_get_preferred_height_for_width (widget, min_width,
692 &minimum_size->height, NULL);
697 natural_size->width = nat_width;
698 gtk_widget_get_preferred_height_for_width (widget, nat_width,
699 NULL, &natural_size->height);
702 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
704 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
708 minimum_size->height = min_height;
709 gtk_widget_get_preferred_width_for_height (widget, min_height,
710 &minimum_size->width, NULL);
715 natural_size->height = nat_height;
716 gtk_widget_get_preferred_width_for_height (widget, nat_height,
717 NULL, &natural_size->width);
724 compare_gap (gconstpointer p1,
728 GtkRequestedSize *sizes = data;
729 const guint *c1 = p1;
730 const guint *c2 = p2;
732 const gint d1 = MAX (sizes[*c1].natural_size -
733 sizes[*c1].minimum_size,
735 const gint d2 = MAX (sizes[*c2].natural_size -
736 sizes[*c2].minimum_size,
739 gint delta = (d2 - d1);
748 * gtk_distribute_natural_allocation:
749 * @extra_space: Extra space to redistribute among children after subtracting
750 * minimum sizes and any child padding from the overall allocation
751 * @n_requested_sizes: Number of requests to fit into the allocation
752 * @sizes: An array of structs with a client pointer and a minimum/natural size
753 * in the orientation of the allocation.
755 * Distributes @extra_space to child @sizes by bringing smaller
756 * children up to natural size first.
758 * The remaining space will be added to the @minimum_size member of the
759 * GtkRequestedSize struct. If all sizes reach their natural size then
760 * the remaining space is returned.
762 * Returns: The remainder of @extra_space after redistributing space
766 gtk_distribute_natural_allocation (gint extra_space,
767 guint n_requested_sizes,
768 GtkRequestedSize *sizes)
773 g_return_val_if_fail (extra_space >= 0, 0);
775 spreading = g_newa (guint, n_requested_sizes);
777 for (i = 0; i < n_requested_sizes; i++)
780 /* Distribute the container's extra space c_gap. We want to assign
781 * this space such that the sum of extra space assigned to children
782 * (c^i_gap) is equal to c_cap. The case that there's not enough
783 * space for all children to take their natural size needs some
784 * attention. The goals we want to achieve are:
786 * a) Maximize number of children taking their natural size.
787 * b) The allocated size of children should be a continuous
788 * function of c_gap. That is, increasing the container size by
789 * one pixel should never make drastic changes in the distribution.
790 * c) If child i takes its natural size and child j doesn't,
791 * child j should have received at least as much gap as child i.
793 * The following code distributes the additional space by following
797 /* Sort descending by gap and position. */
798 g_qsort_with_data (spreading,
799 n_requested_sizes, sizeof (guint),
802 /* Distribute available space.
803 * This master piece of a loop was conceived by Behdad Esfahbod.
805 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
807 /* Divide remaining space by number of remaining children.
808 * Sort order and reducing remaining space by assigned space
809 * ensures that space is distributed equally.
811 gint glue = (extra_space + i) / (i + 1);
812 gint gap = sizes[(spreading[i])].natural_size
813 - sizes[(spreading[i])].minimum_size;
815 gint extra = MIN (glue, gap);
817 sizes[spreading[i]].minimum_size += extra;
819 extra_space -= extra;