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"
34 /* looks for a cached size request for this for_size. If not
35 * found, returns the oldest entry so it can be overwritten
37 * Note that this caching code was directly derived from
38 * the Clutter toolkit.
41 get_cached_size (SizeRequestCache *cache,
42 GtkSizeGroupMode orientation,
47 SizeRequest *cached_sizes;
49 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
51 cached_sizes = cache->widths;
52 n_sizes = cache->cached_widths;
56 cached_sizes = cache->heights;
57 n_sizes = cache->cached_widths;
60 /* Search for an already cached size */
61 for (i = 0; i < n_sizes; i++)
63 if (cached_sizes[i].for_size == for_size)
65 *result = &cached_sizes[i];
70 /* If not found, pull a new size from the cache, the returned size cache
71 * will immediately be used to cache the new computed size so we go ahead
72 * and increment the last_cached_width/height right away */
73 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
75 if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
77 cache->cached_widths++;
78 cache->last_cached_width = cache->cached_widths - 1;
82 if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
83 cache->last_cached_width = 0;
86 *result = &cache->widths[cache->last_cached_width];
88 else /* GTK_SIZE_GROUP_VERTICAL */
90 if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
92 cache->cached_heights++;
93 cache->last_cached_height = cache->cached_heights - 1;
97 if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
98 cache->last_cached_height = 0;
101 *result = &cache->heights[cache->last_cached_height];
108 do_size_request (GtkWidget *widget,
109 GtkRequisition *requisition)
111 GtkWidgetClass *widget_class = g_type_class_peek (GTK_TYPE_WIDGET);
113 if (GTK_WIDGET_GET_CLASS (widget)->size_request != widget_class->size_request)
114 g_warning ("%s implements GtkWidgetClass::size_request which is deprecated and "
115 "will be removed in the next release",
116 G_OBJECT_TYPE_NAME (widget));
118 /* Now we dont bother caching the deprecated "size-request" returns,
119 * just unconditionally invoke here just in case we run into legacy stuff */
120 gtk_widget_ensure_style (widget);
121 g_signal_emit_by_name (widget, "size-request", requisition);
124 #ifndef G_DISABLE_CHECKS
125 static GQuark recursion_check_quark = 0;
126 #endif /* G_DISABLE_CHECKS */
129 push_recursion_check (GtkWidget *widget,
130 GtkSizeGroupMode orientation,
133 #ifndef G_DISABLE_CHECKS
134 const char *previous_method;
137 if (recursion_check_quark == 0)
138 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
140 previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
142 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
144 method = for_size < 0 ? "get_width" : "get_width_for_height";
148 method = for_size < 0 ? "get_height" : "get_height_for_width";
151 if (previous_method != NULL)
153 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
154 " GtkWidget ::%s implementation. "
155 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
156 "directly rather than using gtk_widget_%s",
157 G_OBJECT_TYPE_NAME (widget), widget,
158 method, previous_method,
162 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
163 #endif /* G_DISABLE_CHECKS */
167 pop_recursion_check (GtkWidget *widget,
168 GtkSizeGroupMode orientation)
170 #ifndef G_DISABLE_CHECKS
171 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
176 compute_size_for_orientation (GtkWidget *widget,
177 GtkSizeGroupMode orientation,
182 SizeRequestCache *cache;
183 SizeRequest *cached_size;
184 gboolean found_in_cache = FALSE;
185 int adjusted_min, adjusted_natural;
187 g_return_if_fail (GTK_IS_WIDGET (widget));
188 g_return_if_fail (minimum_size != NULL || natural_size != NULL);
190 cache = _gtk_widget_peek_request_cache (widget);
192 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
194 cached_size = &cache->widths[0];
196 if (!_gtk_widget_get_width_request_needed (widget))
197 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
200 memset (cache->widths, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
201 cache->cached_widths = 1;
202 cache->last_cached_width = 0;
207 cached_size = &cache->heights[0];
209 if (!_gtk_widget_get_height_request_needed (widget))
210 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
213 memset (cache->heights, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
214 cache->cached_heights = 1;
215 cache->last_cached_height = 0;
221 GtkRequisition requisition = { 0, 0 };
222 gint min_size = 0, nat_size = 0;
223 gint requisition_size;
225 /* Unconditional size request runs but is often unhandled. */
226 do_size_request (widget, &requisition);
228 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
230 requisition_size = requisition.width;
234 push_recursion_check (widget, orientation, for_size);
235 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
236 pop_recursion_check (widget, orientation);
240 int ignored_position = 0;
243 /* Pull the base natural height from the cache as it's needed to adjust
244 * the proposed 'for_size' */
245 gtk_widget_get_preferred_height (widget, NULL, &natural_height);
247 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
248 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
249 GTK_ORIENTATION_VERTICAL,
254 push_recursion_check (widget, orientation, for_size);
255 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget, for_size,
256 &min_size, &nat_size);
257 pop_recursion_check (widget, orientation);
262 requisition_size = requisition.height;
266 push_recursion_check (widget, orientation, for_size);
267 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
268 pop_recursion_check (widget, orientation);
272 int ignored_position = 0;
275 /* Pull the base natural width from the cache as it's needed to adjust
276 * the proposed 'for_size' */
277 gtk_widget_get_preferred_width (widget, NULL, &natural_width);
279 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
280 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
281 GTK_ORIENTATION_HORIZONTAL,
286 push_recursion_check (widget, orientation, for_size);
287 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget, for_size,
288 &min_size, &nat_size);
289 pop_recursion_check (widget, orientation);
293 if (min_size > nat_size)
295 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
296 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
299 /* Support for dangling "size-request" signal implementations on
302 min_size = MAX (min_size, requisition_size);
303 nat_size = MAX (nat_size, requisition_size);
305 cached_size->minimum_size = min_size;
306 cached_size->natural_size = nat_size;
307 cached_size->for_size = for_size;
309 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
310 _gtk_widget_set_width_request_needed (widget, FALSE);
312 _gtk_widget_set_height_request_needed (widget, FALSE);
314 adjusted_min = cached_size->minimum_size;
315 adjusted_natural = cached_size->natural_size;
316 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
317 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
318 GTK_ORIENTATION_HORIZONTAL :
319 GTK_ORIENTATION_VERTICAL,
323 if (adjusted_min < cached_size->minimum_size ||
324 adjusted_natural < cached_size->natural_size)
326 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
327 G_OBJECT_TYPE_NAME (widget), widget,
328 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
329 adjusted_min, adjusted_natural,
330 cached_size->minimum_size, cached_size->natural_size);
331 /* don't use the adjustment */
333 else if (adjusted_min > adjusted_natural)
335 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
336 G_OBJECT_TYPE_NAME (widget), widget,
337 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
338 adjusted_min, adjusted_natural,
339 cached_size->minimum_size, cached_size->natural_size);
340 /* don't use the adjustment */
344 /* adjustment looks good */
345 cached_size->minimum_size = adjusted_min;
346 cached_size->natural_size = adjusted_natural;
349 /* Update size-groups with our request and update our cached requests
350 * with the size-group values in a single pass.
352 _gtk_size_group_bump_requisition (widget,
354 &cached_size->minimum_size,
355 &cached_size->natural_size);
359 *minimum_size = cached_size->minimum_size;
362 *natural_size = cached_size->natural_size;
364 g_assert (cached_size->minimum_size <= cached_size->natural_size);
366 GTK_NOTE (SIZE_REQUEST,
367 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
368 widget, G_OBJECT_TYPE_NAME (widget),
369 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
370 "width for height" : "height for width" ,
372 cached_size->minimum_size,
373 cached_size->natural_size,
374 found_in_cache ? "yes" : "no"));
379 * gtk_widget_get_request_mode:
380 * @widget: a #GtkWidget instance
382 * Gets whether the widget prefers a height-for-width layout
383 * or a width-for-height layout.
385 * <note><para>#GtkBin widgets generally propagate the preference of
386 * their child, container widgets need to request something either in
387 * context of their children or in context of their allocation
388 * capabilities.</para></note>
390 * Returns: The #GtkSizeRequestMode preferred by @widget.
395 gtk_widget_get_request_mode (GtkWidget *widget)
397 GtkWidgetClass *klass;
399 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH);
401 klass = GTK_WIDGET_GET_CLASS (widget);
402 if (klass->get_request_mode)
403 return klass->get_request_mode (widget);
405 /* By default widgets are height-for-width. */
406 return GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH;
410 * gtk_widget_get_preferred_width:
411 * @widget: a #GtkWidget instance
412 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
413 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
415 * Retrieves a widget's initial minimum and natural width.
417 * <note><para>This call is specific to height-for-width
418 * requests.</para></note>
420 * The returned request will be modified by the
421 * GtkWidgetClass::adjust_size_request virtual method and by any
422 * #GtkSizeGroup that have been applied. That is, the returned request
423 * is the one that should be used for layout, not necessarily the one
424 * returned by the widget itself.
429 gtk_widget_get_preferred_width (GtkWidget *widget,
433 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
434 -1, minimum_width, natural_width);
439 * gtk_widget_get_preferred_height:
440 * @widget: a #GtkWidget instance
441 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
442 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
444 * Retrieves a widget's initial minimum and natural height.
446 * <note><para>This call is specific to width-for-height requests.</para></note>
448 * The returned request will be modified by the
449 * GtkWidgetClass::adjust_size_request virtual method and by any
450 * #GtkSizeGroup that have been applied. That is, the returned request
451 * is the one that should be used for layout, not necessarily the one
452 * returned by the widget itself.
457 gtk_widget_get_preferred_height (GtkWidget *widget,
458 gint *minimum_height,
459 gint *natural_height)
461 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
462 -1, minimum_height, natural_height);
468 * gtk_widget_get_preferred_width_for_height:
469 * @widget: a #GtkWidget instance
470 * @height: the height which is available for allocation
471 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
472 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
474 * Retrieves a widget's minimum and natural width if it would be given
475 * the specified @height.
477 * The returned request will be modified by the
478 * GtkWidgetClass::adjust_size_request virtual method and by any
479 * #GtkSizeGroup that have been applied. That is, the returned request
480 * is the one that should be used for layout, not necessarily the one
481 * returned by the widget itself.
486 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
491 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
492 height, minimum_width, natural_width);
496 * gtk_widget_get_preferred_height_for_width:
497 * @widget: a #GtkWidget instance
498 * @width: the width which is available for allocation
499 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
500 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
502 * Retrieves a widget's minimum and natural height if it would be given
503 * the specified @width.
505 * The returned request will be modified by the
506 * GtkWidgetClass::adjust_size_request virtual method and by any
507 * #GtkSizeGroup that have been applied. That is, the returned request
508 * is the one that should be used for layout, not necessarily the one
509 * returned by the widget itself.
514 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
516 gint *minimum_height,
517 gint *natural_height)
519 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
520 width, minimum_height, natural_height);
524 * gtk_widget_get_preferred_size:
525 * @widget: a #GtkWidget instance
526 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
527 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
529 * Retrieves the minimum and natural size of a widget taking
530 * into account the widget's preference for height-for-width management.
532 * This is used to retrieve a suitable size by container widgets which do
533 * not impose any restrictions on the child placement. It can be used
534 * to deduce toplevel window and menu sizes as well as child widgets in
535 * free form containers such as GtkLayout.
537 * <note><para>Handle with care, note that the natural height of a height-for-width
538 * widget will generally be a smaller size than the minimum height, since the required
539 * height for the natural width is generally smaller than the required height for
540 * the minimum width.</para></note>
545 gtk_widget_get_preferred_size (GtkWidget *widget,
546 GtkRequisition *minimum_size,
547 GtkRequisition *natural_size)
549 gint min_width, nat_width;
550 gint min_height, nat_height;
552 g_return_if_fail (GTK_IS_WIDGET (widget));
554 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
556 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
560 minimum_size->width = min_width;
561 gtk_widget_get_preferred_height_for_width (widget, min_width,
562 &minimum_size->height, NULL);
567 natural_size->width = nat_width;
568 gtk_widget_get_preferred_height_for_width (widget, nat_width,
569 NULL, &natural_size->height);
572 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT */
574 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
578 minimum_size->height = min_height;
579 gtk_widget_get_preferred_width_for_height (widget, min_height,
580 &minimum_size->width, NULL);
585 natural_size->height = nat_height;
586 gtk_widget_get_preferred_width_for_height (widget, nat_height,
587 NULL, &natural_size->width);
594 compare_gap (gconstpointer p1,
598 GtkRequestedSize *sizes = data;
599 const guint *c1 = p1;
600 const guint *c2 = p2;
602 const gint d1 = MAX (sizes[*c1].natural_size -
603 sizes[*c1].minimum_size,
605 const gint d2 = MAX (sizes[*c2].natural_size -
606 sizes[*c2].minimum_size,
609 gint delta = (d2 - d1);
618 * gtk_distribute_natural_allocation:
619 * @extra_space: Extra space to redistribute among children after subtracting
620 * minimum sizes and any child padding from the overall allocation
621 * @n_requested_sizes: Number of requests to fit into the allocation
622 * @sizes: An array of structs with a client pointer and a minimum/natural size
623 * in the orientation of the allocation.
625 * Distributes @extra_space to child @sizes by bringing up smaller
626 * children up to natural size first.
628 * The remaining space will be added to the @minimum_size member of the
629 * GtkRequestedSize struct. If all sizes reach their natural size then
630 * the remaining space is returned.
632 * Returns: The remainder of @extra_space after redistributing space
636 gtk_distribute_natural_allocation (gint extra_space,
637 guint n_requested_sizes,
638 GtkRequestedSize *sizes)
643 g_return_val_if_fail (extra_space >= 0, 0);
645 spreading = g_newa (guint, n_requested_sizes);
647 for (i = 0; i < n_requested_sizes; i++)
650 /* Distribute the container's extra space c_gap. We want to assign
651 * this space such that the sum of extra space assigned to children
652 * (c^i_gap) is equal to c_cap. The case that there's not enough
653 * space for all children to take their natural size needs some
654 * attention. The goals we want to achieve are:
656 * a) Maximize number of children taking their natural size.
657 * b) The allocated size of children should be a continuous
658 * function of c_gap. That is, increasing the container size by
659 * one pixel should never make drastic changes in the distribution.
660 * c) If child i takes its natural size and child j doesn't,
661 * child j should have received at least as much gap as child i.
663 * The following code distributes the additional space by following
667 /* Sort descending by gap and position. */
668 g_qsort_with_data (spreading,
669 n_requested_sizes, sizeof (guint),
672 /* Distribute available space.
673 * This master piece of a loop was conceived by Behdad Esfahbod.
675 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
677 /* Divide remaining space by number of remaining children.
678 * Sort order and reducing remaining space by assigned space
679 * ensures that space is distributed equally.
681 gint glue = (extra_space + i) / (i + 1);
682 gint gap = sizes[(spreading[i])].natural_size
683 - sizes[(spreading[i])].minimum_size;
685 gint extra = MIN (glue, gap);
687 sizes[spreading[i]].minimum_size += extra;
689 extra_space -= extra;