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);
147 if (_gtk_widget_get_height_request_needed (widget))
148 clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
153 /* looks for a cached size request for this for_size. If not
154 * found, returns the oldest entry so it can be overwritten
156 * Note that this caching code was originally derived from
157 * the Clutter toolkit but has evolved for other GTK+ requirements.
160 get_cached_size (GtkWidget *widget,
161 GtkSizeGroupMode orientation,
165 SizeRequestCache *cache;
166 SizeRequest **cached_sizes;
169 cache = init_cache (widget);
173 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
175 *result = &cache->cached_width;
176 return cache->cached_base_width;
180 *result = &cache->cached_height;
181 return cache->cached_base_height;
185 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
187 cached_sizes = cache->widths;
188 n_sizes = cache->cached_widths;
192 cached_sizes = cache->heights;
193 n_sizes = cache->cached_heights;
196 /* Search for an already cached size */
197 for (i = 0; i < n_sizes; i++)
199 if (cached_sizes[i]->lower_for_size <= for_size &&
200 cached_sizes[i]->upper_for_size >= for_size)
202 *result = &cached_sizes[i]->cached_size;
211 commit_cached_size (GtkWidget *widget,
212 GtkSizeGroupMode orientation,
217 SizeRequestCache *cache;
218 SizeRequest **cached_sizes;
221 cache = _gtk_widget_peek_request_cache (widget);
223 /* First handle caching of the base requests */
226 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
228 cache->cached_width.minimum_size = minimum_size;
229 cache->cached_width.natural_size = natural_size;
230 cache->cached_base_width = TRUE;
234 cache->cached_height.minimum_size = minimum_size;
235 cache->cached_height.natural_size = natural_size;
236 cache->cached_base_height = TRUE;
241 /* Check if the minimum_size and natural_size is already
242 * in the cache and if this result can be used to extend
245 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
247 cached_sizes = cache->widths;
248 n_sizes = cache->cached_widths;
252 cached_sizes = cache->heights;
253 n_sizes = cache->cached_heights;
256 for (i = 0; i < n_sizes; i++)
258 if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
259 cached_sizes[i]->cached_size.natural_size == natural_size)
261 cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
262 cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
267 /* If not found, pull a new size from the cache, the returned size cache
268 * will immediately be used to cache the new computed size so we go ahead
269 * and increment the last_cached_width/height right away */
270 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
272 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
274 cache->cached_widths++;
275 cache->last_cached_width = cache->cached_widths - 1;
279 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
280 cache->last_cached_width = 0;
284 cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
286 if (!cache->widths[cache->last_cached_width])
287 cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
289 cache->widths[cache->last_cached_width]->lower_for_size = for_size;
290 cache->widths[cache->last_cached_width]->upper_for_size = for_size;
291 cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
292 cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
294 else /* GTK_SIZE_GROUP_VERTICAL */
296 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
298 cache->cached_heights++;
299 cache->last_cached_height = cache->cached_heights - 1;
303 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
304 cache->last_cached_height = 0;
308 cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
310 if (!cache->heights[cache->last_cached_height])
311 cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
313 cache->heights[cache->last_cached_height]->lower_for_size = for_size;
314 cache->heights[cache->last_cached_height]->upper_for_size = for_size;
315 cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
316 cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
320 /* This is the main function that checks for a cached size and
321 * possibly queries the widget class to compute the size if it's
322 * not cached. If the for_size here is -1, then get_preferred_width()
323 * or get_preferred_height() will be used.
326 compute_size_for_orientation (GtkWidget *widget,
327 GtkSizeGroupMode orientation,
332 CachedSize *cached_size;
333 gboolean found_in_cache = FALSE;
337 found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
341 gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
343 gtk_widget_ensure_style (widget);
345 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
349 push_recursion_check (widget, orientation, for_size);
350 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
351 pop_recursion_check (widget, orientation);
355 gint ignored_position = 0;
359 /* Pull the base natural height from the cache as it's needed to adjust
360 * the proposed 'for_size' */
361 gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
363 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
364 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
365 GTK_ORIENTATION_VERTICAL,
371 push_recursion_check (widget, orientation, for_size);
372 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget,
373 MAX (adjusted_for_size, minimum_height),
374 &min_size, &nat_size);
375 pop_recursion_check (widget, orientation);
382 push_recursion_check (widget, orientation, for_size);
383 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
384 pop_recursion_check (widget, orientation);
388 gint ignored_position = 0;
392 /* Pull the base natural width from the cache as it's needed to adjust
393 * the proposed 'for_size' */
394 gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
396 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
397 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
398 GTK_ORIENTATION_HORIZONTAL,
404 push_recursion_check (widget, orientation, for_size);
405 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget,
406 MAX (adjusted_for_size, minimum_width),
407 &min_size, &nat_size);
408 pop_recursion_check (widget, orientation);
412 if (min_size > nat_size)
414 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
415 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
418 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
419 _gtk_widget_set_width_request_needed (widget, FALSE);
421 _gtk_widget_set_height_request_needed (widget, FALSE);
423 adjusted_min = min_size;
424 adjusted_natural = nat_size;
425 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
426 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
427 GTK_ORIENTATION_HORIZONTAL :
428 GTK_ORIENTATION_VERTICAL,
432 if (adjusted_min < min_size ||
433 adjusted_natural < nat_size)
435 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
436 G_OBJECT_TYPE_NAME (widget), widget,
437 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
438 adjusted_min, adjusted_natural,
440 /* don't use the adjustment */
442 else if (adjusted_min > adjusted_natural)
444 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
445 G_OBJECT_TYPE_NAME (widget), widget,
446 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
447 adjusted_min, adjusted_natural,
449 /* don't use the adjustment */
453 /* adjustment looks good */
454 min_size = adjusted_min;
455 nat_size = adjusted_natural;
458 /* Update size-groups with our request and update our cached requests
459 * with the size-group values in a single pass.
461 _gtk_size_group_bump_requisition (widget,
466 commit_cached_size (widget, orientation, for_size, min_size, nat_size);
470 min_size = cached_size->minimum_size;
471 nat_size = cached_size->natural_size;
475 *minimum_size = min_size;
478 *natural_size = nat_size;
480 g_assert (min_size <= nat_size);
482 GTK_NOTE (SIZE_REQUEST,
483 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
484 widget, G_OBJECT_TYPE_NAME (widget),
485 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
486 "width for height" : "height for width" ,
487 for_size, min_size, nat_size,
488 found_in_cache ? "yes" : "no"));
493 * gtk_widget_get_request_mode:
494 * @widget: a #GtkWidget instance
496 * Gets whether the widget prefers a height-for-width layout
497 * or a width-for-height layout.
499 * <note><para>#GtkBin widgets generally propagate the preference of
500 * their child, container widgets need to request something either in
501 * context of their children or in context of their allocation
502 * capabilities.</para></note>
504 * Returns: The #GtkSizeRequestMode preferred by @widget.
509 gtk_widget_get_request_mode (GtkWidget *widget)
511 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH);
513 return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
517 * gtk_widget_get_preferred_width:
518 * @widget: a #GtkWidget instance
519 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
520 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
522 * Retrieves a widget's initial minimum and natural width.
524 * <note><para>This call is specific to height-for-width
525 * requests.</para></note>
527 * The returned request will be modified by the
528 * GtkWidgetClass::adjust_size_request virtual method and by any
529 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
530 * is the one that should be used for layout, not necessarily the one
531 * returned by the widget itself.
536 gtk_widget_get_preferred_width (GtkWidget *widget,
540 g_return_if_fail (GTK_IS_WIDGET (widget));
541 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
543 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
544 -1, minimum_width, natural_width);
549 * gtk_widget_get_preferred_height:
550 * @widget: a #GtkWidget instance
551 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
552 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
554 * Retrieves a widget's initial minimum and natural height.
556 * <note><para>This call is specific to width-for-height requests.</para></note>
558 * The returned request will be modified by the
559 * GtkWidgetClass::adjust_size_request virtual method and by any
560 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
561 * is the one that should be used for layout, not necessarily the one
562 * returned by the widget itself.
567 gtk_widget_get_preferred_height (GtkWidget *widget,
568 gint *minimum_height,
569 gint *natural_height)
571 g_return_if_fail (GTK_IS_WIDGET (widget));
572 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
574 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
575 -1, minimum_height, natural_height);
581 * gtk_widget_get_preferred_width_for_height:
582 * @widget: a #GtkWidget instance
583 * @height: the height which is available for allocation
584 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
585 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
587 * Retrieves a widget's minimum and natural width if it would be given
588 * the specified @height.
590 * The returned request will be modified by the
591 * GtkWidgetClass::adjust_size_request virtual method and by any
592 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
593 * is the one that should be used for layout, not necessarily the one
594 * returned by the widget itself.
599 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
604 g_return_if_fail (GTK_IS_WIDGET (widget));
605 g_return_if_fail (minimum_width != NULL || natural_width != NULL);
606 g_return_if_fail (height >= 0);
608 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
609 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
610 -1, minimum_width, natural_width);
612 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
613 height, minimum_width, natural_width);
617 * gtk_widget_get_preferred_height_for_width:
618 * @widget: a #GtkWidget instance
619 * @width: the width which is available for allocation
620 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
621 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
623 * Retrieves a widget's minimum and natural height if it would be given
624 * the specified @width.
626 * The returned request will be modified by the
627 * GtkWidgetClass::adjust_size_request virtual method and by any
628 * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
629 * is the one that should be used for layout, not necessarily the one
630 * returned by the widget itself.
635 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
637 gint *minimum_height,
638 gint *natural_height)
640 g_return_if_fail (GTK_IS_WIDGET (widget));
641 g_return_if_fail (minimum_height != NULL || natural_height != NULL);
642 g_return_if_fail (width >= 0);
644 if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
645 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
646 -1, minimum_height, natural_height);
648 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
649 width, minimum_height, natural_height);
653 * gtk_widget_get_preferred_size:
654 * @widget: a #GtkWidget instance
655 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
656 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
658 * Retrieves the minimum and natural size of a widget, taking
659 * into account the widget's preference for height-for-width management.
661 * This is used to retrieve a suitable size by container widgets which do
662 * not impose any restrictions on the child placement. It can be used
663 * to deduce toplevel window and menu sizes as well as child widgets in
664 * free-form containers such as GtkLayout.
666 * <note><para>Handle with care. Note that the natural height of a height-for-width
667 * widget will generally be a smaller size than the minimum height, since the required
668 * height for the natural width is generally smaller than the required height for
669 * the minimum width.</para></note>
674 gtk_widget_get_preferred_size (GtkWidget *widget,
675 GtkRequisition *minimum_size,
676 GtkRequisition *natural_size)
678 gint min_width, nat_width;
679 gint min_height, nat_height;
681 g_return_if_fail (GTK_IS_WIDGET (widget));
683 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
685 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
689 minimum_size->width = min_width;
690 gtk_widget_get_preferred_height_for_width (widget, min_width,
691 &minimum_size->height, NULL);
696 natural_size->width = nat_width;
697 gtk_widget_get_preferred_height_for_width (widget, nat_width,
698 NULL, &natural_size->height);
701 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
703 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
707 minimum_size->height = min_height;
708 gtk_widget_get_preferred_width_for_height (widget, min_height,
709 &minimum_size->width, NULL);
714 natural_size->height = nat_height;
715 gtk_widget_get_preferred_width_for_height (widget, nat_height,
716 NULL, &natural_size->width);
723 compare_gap (gconstpointer p1,
727 GtkRequestedSize *sizes = data;
728 const guint *c1 = p1;
729 const guint *c2 = p2;
731 const gint d1 = MAX (sizes[*c1].natural_size -
732 sizes[*c1].minimum_size,
734 const gint d2 = MAX (sizes[*c2].natural_size -
735 sizes[*c2].minimum_size,
738 gint delta = (d2 - d1);
747 * gtk_distribute_natural_allocation:
748 * @extra_space: Extra space to redistribute among children after subtracting
749 * minimum sizes and any child padding from the overall allocation
750 * @n_requested_sizes: Number of requests to fit into the allocation
751 * @sizes: An array of structs with a client pointer and a minimum/natural size
752 * in the orientation of the allocation.
754 * Distributes @extra_space to child @sizes by bringing smaller
755 * children up to natural size first.
757 * The remaining space will be added to the @minimum_size member of the
758 * GtkRequestedSize struct. If all sizes reach their natural size then
759 * the remaining space is returned.
761 * Returns: The remainder of @extra_space after redistributing space
765 gtk_distribute_natural_allocation (gint extra_space,
766 guint n_requested_sizes,
767 GtkRequestedSize *sizes)
772 g_return_val_if_fail (extra_space >= 0, 0);
774 spreading = g_newa (guint, n_requested_sizes);
776 for (i = 0; i < n_requested_sizes; i++)
779 /* Distribute the container's extra space c_gap. We want to assign
780 * this space such that the sum of extra space assigned to children
781 * (c^i_gap) is equal to c_cap. The case that there's not enough
782 * space for all children to take their natural size needs some
783 * attention. The goals we want to achieve are:
785 * a) Maximize number of children taking their natural size.
786 * b) The allocated size of children should be a continuous
787 * function of c_gap. That is, increasing the container size by
788 * one pixel should never make drastic changes in the distribution.
789 * c) If child i takes its natural size and child j doesn't,
790 * child j should have received at least as much gap as child i.
792 * The following code distributes the additional space by following
796 /* Sort descending by gap and position. */
797 g_qsort_with_data (spreading,
798 n_requested_sizes, sizeof (guint),
801 /* Distribute available space.
802 * This master piece of a loop was conceived by Behdad Esfahbod.
804 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
806 /* Divide remaining space by number of remaining children.
807 * Sort order and reducing remaining space by assigned space
808 * ensures that space is distributed equally.
810 gint glue = (extra_space + i) / (i + 1);
811 gint gap = sizes[(spreading[i])].natural_size
812 - sizes[(spreading[i])].minimum_size;
814 gint extra = MIN (glue, gap);
816 sizes[spreading[i]].minimum_size += extra;
818 extra_space -= extra;