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 extern guint size_request_signal_id;
110 do_size_request (GtkWidget *widget,
111 GtkRequisition *requisition)
113 GtkWidgetClass *widget_class = g_type_class_peek (GTK_TYPE_WIDGET);
115 if (GTK_WIDGET_GET_CLASS (widget)->size_request != widget_class->size_request)
116 g_warning ("%s implements GtkWidgetClass::size_request which is deprecated and "
117 "will be removed in the next release",
118 G_OBJECT_TYPE_NAME (widget));
120 if (g_signal_has_handler_pending (widget, size_request_signal_id, 0, TRUE))
121 g_warning ("A %s (%p) has handler(s) connected to the GtkWidgetClass::size-request signal which is "
122 "deprecated and will be removed in the next release",
123 G_OBJECT_TYPE_NAME (widget), widget);
125 /* Now we dont bother caching the deprecated "size-request" returns,
126 * just unconditionally invoke here just in case we run into legacy stuff */
127 gtk_widget_ensure_style (widget);
128 g_signal_emit_by_name (widget, "size-request", requisition);
131 #ifndef G_DISABLE_CHECKS
132 static GQuark recursion_check_quark = 0;
133 #endif /* G_DISABLE_CHECKS */
136 push_recursion_check (GtkWidget *widget,
137 GtkSizeGroupMode orientation,
140 #ifndef G_DISABLE_CHECKS
141 const char *previous_method;
144 if (recursion_check_quark == 0)
145 recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
147 previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
149 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
151 method = for_size < 0 ? "get_width" : "get_width_for_height";
155 method = for_size < 0 ? "get_height" : "get_height_for_width";
158 if (previous_method != NULL)
160 g_warning ("%s %p: widget tried to gtk_widget_%s inside "
161 " GtkWidget ::%s implementation. "
162 "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
163 "directly rather than using gtk_widget_%s",
164 G_OBJECT_TYPE_NAME (widget), widget,
165 method, previous_method,
169 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
170 #endif /* G_DISABLE_CHECKS */
174 pop_recursion_check (GtkWidget *widget,
175 GtkSizeGroupMode orientation)
177 #ifndef G_DISABLE_CHECKS
178 g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
183 compute_size_for_orientation (GtkWidget *widget,
184 GtkSizeGroupMode orientation,
189 SizeRequestCache *cache;
190 SizeRequest *cached_size;
191 gboolean found_in_cache = FALSE;
192 int adjusted_min, adjusted_natural;
194 g_return_if_fail (GTK_IS_WIDGET (widget));
195 g_return_if_fail (minimum_size != NULL || natural_size != NULL);
197 cache = _gtk_widget_peek_request_cache (widget);
199 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
201 cached_size = &cache->widths[0];
203 if (!_gtk_widget_get_width_request_needed (widget))
204 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
207 memset (cache->widths, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
208 cache->cached_widths = 1;
209 cache->last_cached_width = 0;
214 cached_size = &cache->heights[0];
216 if (!_gtk_widget_get_height_request_needed (widget))
217 found_in_cache = get_cached_size (cache, orientation, for_size, &cached_size);
220 memset (cache->heights, 0, GTK_SIZE_REQUEST_CACHED_SIZES * sizeof (SizeRequest));
221 cache->cached_heights = 1;
222 cache->last_cached_height = 0;
228 GtkRequisition requisition = { 0, 0 };
229 gint min_size = 0, nat_size = 0;
230 gint requisition_size;
232 /* Unconditional size request runs but is often unhandled. */
233 do_size_request (widget, &requisition);
235 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
237 requisition_size = requisition.width;
241 push_recursion_check (widget, orientation, for_size);
242 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
243 pop_recursion_check (widget, orientation);
247 int ignored_position = 0;
250 /* Pull the base natural height from the cache as it's needed to adjust
251 * the proposed 'for_size' */
252 gtk_widget_get_preferred_height (widget, NULL, &natural_height);
254 /* convert for_size to unadjusted height (for_size is a proposed allocation) */
255 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
256 GTK_ORIENTATION_VERTICAL,
261 push_recursion_check (widget, orientation, for_size);
262 GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget, for_size,
263 &min_size, &nat_size);
264 pop_recursion_check (widget, orientation);
269 requisition_size = requisition.height;
273 push_recursion_check (widget, orientation, for_size);
274 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
275 pop_recursion_check (widget, orientation);
279 int ignored_position = 0;
282 /* Pull the base natural width from the cache as it's needed to adjust
283 * the proposed 'for_size' */
284 gtk_widget_get_preferred_width (widget, NULL, &natural_width);
286 /* convert for_size to unadjusted width (for_size is a proposed allocation) */
287 GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
288 GTK_ORIENTATION_HORIZONTAL,
293 push_recursion_check (widget, orientation, for_size);
294 GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget, for_size,
295 &min_size, &nat_size);
296 pop_recursion_check (widget, orientation);
300 if (min_size > nat_size)
302 g_warning ("%s %p reported min size %d and natural size %d; natural size must be >= min size",
303 G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size);
306 /* Support for dangling "size-request" signal implementations on
309 min_size = MAX (min_size, requisition_size);
310 nat_size = MAX (nat_size, requisition_size);
312 cached_size->minimum_size = min_size;
313 cached_size->natural_size = nat_size;
314 cached_size->for_size = for_size;
316 if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
317 _gtk_widget_set_width_request_needed (widget, FALSE);
319 _gtk_widget_set_height_request_needed (widget, FALSE);
321 adjusted_min = cached_size->minimum_size;
322 adjusted_natural = cached_size->natural_size;
323 GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
324 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
325 GTK_ORIENTATION_HORIZONTAL :
326 GTK_ORIENTATION_VERTICAL,
330 if (adjusted_min < cached_size->minimum_size ||
331 adjusted_natural < cached_size->natural_size)
333 g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
334 G_OBJECT_TYPE_NAME (widget), widget,
335 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
336 adjusted_min, adjusted_natural,
337 cached_size->minimum_size, cached_size->natural_size);
338 /* don't use the adjustment */
340 else if (adjusted_min > adjusted_natural)
342 g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
343 G_OBJECT_TYPE_NAME (widget), widget,
344 orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
345 adjusted_min, adjusted_natural,
346 cached_size->minimum_size, cached_size->natural_size);
347 /* don't use the adjustment */
351 /* adjustment looks good */
352 cached_size->minimum_size = adjusted_min;
353 cached_size->natural_size = adjusted_natural;
356 /* Update size-groups with our request and update our cached requests
357 * with the size-group values in a single pass.
359 _gtk_size_group_bump_requisition (widget,
361 &cached_size->minimum_size,
362 &cached_size->natural_size);
366 *minimum_size = cached_size->minimum_size;
369 *natural_size = cached_size->natural_size;
371 g_assert (cached_size->minimum_size <= cached_size->natural_size);
373 GTK_NOTE (SIZE_REQUEST,
374 g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
375 widget, G_OBJECT_TYPE_NAME (widget),
376 orientation == GTK_SIZE_GROUP_HORIZONTAL ?
377 "width for height" : "height for width" ,
379 cached_size->minimum_size,
380 cached_size->natural_size,
381 found_in_cache ? "yes" : "no"));
386 * gtk_widget_get_request_mode:
387 * @widget: a #GtkWidget instance
389 * Gets whether the widget prefers a height-for-width layout
390 * or a width-for-height layout.
392 * <note><para>#GtkBin widgets generally propagate the preference of
393 * their child, container widgets need to request something either in
394 * context of their children or in context of their allocation
395 * capabilities.</para></note>
397 * Returns: The #GtkSizeRequestMode preferred by @widget.
402 gtk_widget_get_request_mode (GtkWidget *widget)
404 GtkWidgetClass *klass;
406 g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH);
408 klass = GTK_WIDGET_GET_CLASS (widget);
409 if (klass->get_request_mode)
410 return klass->get_request_mode (widget);
412 /* By default widgets are height-for-width. */
413 return GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH;
417 * gtk_widget_get_preferred_width:
418 * @widget: a #GtkWidget instance
419 * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
420 * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
422 * Retrieves a widget's initial minimum and natural width.
424 * <note><para>This call is specific to height-for-width
425 * requests.</para></note>
427 * The returned request will be modified by the
428 * GtkWidgetClass::adjust_size_request virtual method and by any
429 * #GtkSizeGroup that have been applied. That is, the returned request
430 * is the one that should be used for layout, not necessarily the one
431 * returned by the widget itself.
436 gtk_widget_get_preferred_width (GtkWidget *widget,
440 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
441 -1, minimum_width, natural_width);
446 * gtk_widget_get_preferred_height:
447 * @widget: a #GtkWidget instance
448 * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
449 * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
451 * Retrieves a widget's initial minimum and natural height.
453 * <note><para>This call is specific to width-for-height requests.</para></note>
455 * The returned request will be modified by the
456 * GtkWidgetClass::adjust_size_request virtual method and by any
457 * #GtkSizeGroup that have been applied. That is, the returned request
458 * is the one that should be used for layout, not necessarily the one
459 * returned by the widget itself.
464 gtk_widget_get_preferred_height (GtkWidget *widget,
465 gint *minimum_height,
466 gint *natural_height)
468 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
469 -1, minimum_height, natural_height);
475 * gtk_widget_get_preferred_width_for_height:
476 * @widget: a #GtkWidget instance
477 * @height: the height which is available for allocation
478 * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
479 * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
481 * Retrieves a widget's minimum and natural width if it would be given
482 * the specified @height.
484 * The returned request will be modified by the
485 * GtkWidgetClass::adjust_size_request virtual method and by any
486 * #GtkSizeGroup that have been applied. That is, the returned request
487 * is the one that should be used for layout, not necessarily the one
488 * returned by the widget itself.
493 gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
498 compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
499 height, minimum_width, natural_width);
503 * gtk_widget_get_preferred_height_for_width:
504 * @widget: a #GtkWidget instance
505 * @width: the width which is available for allocation
506 * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
507 * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
509 * Retrieves a widget's minimum and natural height if it would be given
510 * the specified @width.
512 * The returned request will be modified by the
513 * GtkWidgetClass::adjust_size_request virtual method and by any
514 * #GtkSizeGroup that have been applied. That is, the returned request
515 * is the one that should be used for layout, not necessarily the one
516 * returned by the widget itself.
521 gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
523 gint *minimum_height,
524 gint *natural_height)
526 compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
527 width, minimum_height, natural_height);
531 * gtk_widget_get_preferred_size:
532 * @widget: a #GtkWidget instance
533 * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
534 * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
536 * Retrieves the minimum and natural size of a widget taking
537 * into account the widget's preference for height-for-width management.
539 * This is used to retrieve a suitable size by container widgets which do
540 * not impose any restrictions on the child placement. It can be used
541 * to deduce toplevel window and menu sizes as well as child widgets in
542 * free form containers such as GtkLayout.
544 * <note><para>Handle with care, note that the natural height of a height-for-width
545 * widget will generally be a smaller size than the minimum height, since the required
546 * height for the natural width is generally smaller than the required height for
547 * the minimum width.</para></note>
552 gtk_widget_get_preferred_size (GtkWidget *widget,
553 GtkRequisition *minimum_size,
554 GtkRequisition *natural_size)
556 gint min_width, nat_width;
557 gint min_height, nat_height;
559 g_return_if_fail (GTK_IS_WIDGET (widget));
561 if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
563 gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
567 minimum_size->width = min_width;
568 gtk_widget_get_preferred_height_for_width (widget, min_width,
569 &minimum_size->height, NULL);
574 natural_size->width = nat_width;
575 gtk_widget_get_preferred_height_for_width (widget, nat_width,
576 NULL, &natural_size->height);
579 else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT */
581 gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
585 minimum_size->height = min_height;
586 gtk_widget_get_preferred_width_for_height (widget, min_height,
587 &minimum_size->width, NULL);
592 natural_size->height = nat_height;
593 gtk_widget_get_preferred_width_for_height (widget, nat_height,
594 NULL, &natural_size->width);
601 compare_gap (gconstpointer p1,
605 GtkRequestedSize *sizes = data;
606 const guint *c1 = p1;
607 const guint *c2 = p2;
609 const gint d1 = MAX (sizes[*c1].natural_size -
610 sizes[*c1].minimum_size,
612 const gint d2 = MAX (sizes[*c2].natural_size -
613 sizes[*c2].minimum_size,
616 gint delta = (d2 - d1);
625 * gtk_distribute_natural_allocation:
626 * @extra_space: Extra space to redistribute among children after subtracting
627 * minimum sizes and any child padding from the overall allocation
628 * @n_requested_sizes: Number of requests to fit into the allocation
629 * @sizes: An array of structs with a client pointer and a minimum/natural size
630 * in the orientation of the allocation.
632 * Distributes @extra_space to child @sizes by bringing up smaller
633 * children up to natural size first.
635 * The remaining space will be added to the @minimum_size member of the
636 * GtkRequestedSize struct. If all sizes reach their natural size then
637 * the remaining space is returned.
639 * Returns: The remainder of @extra_space after redistributing space
643 gtk_distribute_natural_allocation (gint extra_space,
644 guint n_requested_sizes,
645 GtkRequestedSize *sizes)
650 g_return_val_if_fail (extra_space >= 0, 0);
652 spreading = g_newa (guint, n_requested_sizes);
654 for (i = 0; i < n_requested_sizes; i++)
657 /* Distribute the container's extra space c_gap. We want to assign
658 * this space such that the sum of extra space assigned to children
659 * (c^i_gap) is equal to c_cap. The case that there's not enough
660 * space for all children to take their natural size needs some
661 * attention. The goals we want to achieve are:
663 * a) Maximize number of children taking their natural size.
664 * b) The allocated size of children should be a continuous
665 * function of c_gap. That is, increasing the container size by
666 * one pixel should never make drastic changes in the distribution.
667 * c) If child i takes its natural size and child j doesn't,
668 * child j should have received at least as much gap as child i.
670 * The following code distributes the additional space by following
674 /* Sort descending by gap and position. */
675 g_qsort_with_data (spreading,
676 n_requested_sizes, sizeof (guint),
679 /* Distribute available space.
680 * This master piece of a loop was conceived by Behdad Esfahbod.
682 for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
684 /* Divide remaining space by number of remaining children.
685 * Sort order and reducing remaining space by assigned space
686 * ensures that space is distributed equally.
688 gint glue = (extra_space + i) / (i + 1);
689 gint gap = sizes[(spreading[i])].natural_size
690 - sizes[(spreading[i])].minimum_size;
692 gint extra = MIN (glue, gap);
694 sizes[spreading[i]].minimum_size += extra;
696 extra_space -= extra;