832 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			832 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* gtksizerequest.c
 | |
|  * Copyright (C) 2007-2010 Openismus GmbH
 | |
|  *
 | |
|  * Authors:
 | |
|  *      Mathias Hasselmann <mathias@openismus.com>
 | |
|  *      Tristan Van Berkom <tristan.van.berkom@gmail.com>
 | |
|  *
 | |
|  * This library is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU Library General Public
 | |
|  * License as published by the Free Software Foundation; either
 | |
|  * version 2 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  * This library is distributed in the hope that it will be useful,
 | |
|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | |
|  * Library General Public License for more details.
 | |
|  *
 | |
|  * You should have received a copy of the GNU Library General Public
 | |
|  * License along with this library. If not, see <http://www.gnu.org/licenses/>.
 | |
|  */
 | |
| 
 | |
| #include <config.h>
 | |
| 
 | |
| #include "gtksizerequest.h"
 | |
| 
 | |
| #include "gtkdebug.h"
 | |
| #include "gtkintl.h"
 | |
| #include "gtkprivate.h"
 | |
| #include "gtksizegroup-private.h"
 | |
| #include "gtkwidgetprivate.h"
 | |
| #include "deprecated/gtkstyle.h"
 | |
| 
 | |
| 
 | |
| #ifndef G_DISABLE_CHECKS
 | |
| static GQuark recursion_check_quark = 0;
 | |
| #endif /* G_DISABLE_CHECKS */
 | |
| 
 | |
| static void
 | |
| push_recursion_check (GtkWidget       *widget,
 | |
|                       GtkSizeGroupMode orientation,
 | |
|                       gint             for_size)
 | |
| {
 | |
| #ifndef G_DISABLE_CHECKS
 | |
|   const char *previous_method;
 | |
|   const char *method;
 | |
| 
 | |
|   if (recursion_check_quark == 0)
 | |
|     recursion_check_quark = g_quark_from_static_string ("gtk-size-request-in-progress");
 | |
| 
 | |
|   previous_method = g_object_get_qdata (G_OBJECT (widget), recursion_check_quark);
 | |
| 
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     {
 | |
|       method = for_size < 0 ? "get_width" : "get_width_for_height";
 | |
|     }
 | |
|   else
 | |
|     {
 | |
|       method = for_size < 0 ? "get_height" : "get_height_for_width";
 | |
|     }
 | |
| 
 | |
|   if (previous_method != NULL)
 | |
|     {
 | |
|       g_warning ("%s %p: widget tried to gtk_widget_%s inside "
 | |
|                  " GtkWidget     ::%s implementation. "
 | |
|                  "Should just invoke GTK_WIDGET_GET_CLASS(widget)->%s "
 | |
|                  "directly rather than using gtk_widget_%s",
 | |
|                  G_OBJECT_TYPE_NAME (widget), widget,
 | |
|                  method, previous_method,
 | |
|                  method, method);
 | |
|     }
 | |
| 
 | |
|   g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, (char*) method);
 | |
| #endif /* G_DISABLE_CHECKS */
 | |
| }
 | |
| 
 | |
| static void
 | |
| pop_recursion_check (GtkWidget       *widget,
 | |
|                      GtkSizeGroupMode orientation)
 | |
| {
 | |
| #ifndef G_DISABLE_CHECKS
 | |
|   g_object_set_qdata (G_OBJECT (widget), recursion_check_quark, NULL);
 | |
| #endif
 | |
| }
 | |
| 
 | |
| 
 | |
| static void
 | |
| clear_cache (SizeRequestCache   *cache,
 | |
| 	     GtkSizeGroupMode    orientation)
 | |
| {
 | |
|   SizeRequest **sizes;
 | |
|   gint          i;
 | |
| 
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     {
 | |
|       sizes = cache->widths;
 | |
| 
 | |
|       cache->widths            = NULL;
 | |
|       cache->cached_widths     = 0;
 | |
|       cache->last_cached_width = 0;
 | |
|       cache->cached_base_width = FALSE;
 | |
|     }
 | |
|   else
 | |
|     {
 | |
|       sizes = cache->heights;
 | |
| 
 | |
|       cache->heights            = NULL;
 | |
|       cache->cached_heights     = 0;
 | |
|       cache->last_cached_height = 0; 
 | |
|       cache->cached_base_height = FALSE;
 | |
|    }
 | |
| 
 | |
|   if (sizes)
 | |
|     {
 | |
|       for (i = 0; i < GTK_SIZE_REQUEST_CACHED_SIZES && sizes[i] != NULL; i++)
 | |
| 	g_slice_free (SizeRequest, sizes[i]);
 | |
|       
 | |
|       g_slice_free1 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES, sizes);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void
 | |
| _gtk_widget_free_cached_sizes (GtkWidget *widget)
 | |
| {
 | |
|   SizeRequestCache   *cache;
 | |
| 
 | |
|   cache = _gtk_widget_peek_request_cache (widget);
 | |
| 
 | |
|   clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
 | |
|   clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
 | |
| }
 | |
| 
 | |
| /* This function checks if 'request_needed' flag is present
 | |
|  * and resets the cache state if a request is needed for
 | |
|  * a given orientation.
 | |
|  */
 | |
| static SizeRequestCache *
 | |
| init_cache (GtkWidget        *widget)
 | |
| {
 | |
|   SizeRequestCache *cache;
 | |
| 
 | |
|   cache = _gtk_widget_peek_request_cache (widget);
 | |
| 
 | |
|   if (_gtk_widget_get_width_request_needed (widget))
 | |
|     clear_cache (cache, GTK_SIZE_GROUP_HORIZONTAL);
 | |
|   
 | |
|   if (_gtk_widget_get_height_request_needed (widget))
 | |
|     clear_cache (cache, GTK_SIZE_GROUP_VERTICAL);
 | |
| 
 | |
|   return cache;
 | |
| }
 | |
| 
 | |
| /* looks for a cached size request for this for_size. If not
 | |
|  * found, returns the oldest entry so it can be overwritten
 | |
|  *
 | |
|  * Note that this caching code was originally derived from
 | |
|  * the Clutter toolkit but has evolved for other GTK+ requirements.
 | |
|  */
 | |
| static gboolean
 | |
| get_cached_size (GtkWidget         *widget,
 | |
| 		 GtkSizeGroupMode   orientation,
 | |
| 		 gint               for_size,
 | |
| 		 CachedSize       **result)
 | |
| {
 | |
|   SizeRequestCache  *cache;
 | |
|   SizeRequest      **cached_sizes;
 | |
|   guint              i, n_sizes;
 | |
| 
 | |
|   cache = init_cache (widget);
 | |
| 
 | |
|   if (for_size < 0)
 | |
|     {
 | |
|       if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
| 	{
 | |
| 	  *result = &cache->cached_width;
 | |
| 	  return cache->cached_base_width;
 | |
| 	}
 | |
|       else
 | |
| 	{
 | |
| 	  *result = &cache->cached_height;
 | |
| 	  return cache->cached_base_height;
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     {
 | |
|       cached_sizes = cache->widths;
 | |
|       n_sizes      = cache->cached_widths;
 | |
|     }
 | |
|   else
 | |
|     {
 | |
|       cached_sizes = cache->heights;
 | |
|       n_sizes      = cache->cached_heights;
 | |
|     }
 | |
| 
 | |
|   /* Search for an already cached size */
 | |
|   for (i = 0; i < n_sizes; i++)
 | |
|     {
 | |
|       if (cached_sizes[i]->lower_for_size <= for_size &&
 | |
| 	  cached_sizes[i]->upper_for_size >= for_size)
 | |
| 	{
 | |
| 	  *result = &cached_sizes[i]->cached_size;
 | |
| 	  return TRUE;
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|   return FALSE;
 | |
| }
 | |
| 
 | |
| static void
 | |
| commit_cached_size (GtkWidget         *widget,
 | |
| 		    GtkSizeGroupMode   orientation,
 | |
| 		    gint               for_size,
 | |
| 		    gint               minimum_size,
 | |
| 		    gint               natural_size)
 | |
| {
 | |
|   SizeRequestCache  *cache;
 | |
|   SizeRequest      **cached_sizes;
 | |
|   guint              i, n_sizes;
 | |
| 
 | |
|   cache = _gtk_widget_peek_request_cache (widget);
 | |
| 
 | |
|   /* First handle caching of the base requests */
 | |
|   if (for_size < 0)
 | |
|     {
 | |
|       if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
| 	{
 | |
| 	  cache->cached_width.minimum_size = minimum_size;
 | |
| 	  cache->cached_width.natural_size = natural_size;
 | |
| 	  cache->cached_base_width = TRUE;
 | |
| 	}
 | |
|       else
 | |
| 	{
 | |
| 	  cache->cached_height.minimum_size = minimum_size;
 | |
| 	  cache->cached_height.natural_size = natural_size;
 | |
| 	  cache->cached_base_height = TRUE;
 | |
| 	}
 | |
|       return;
 | |
|     }
 | |
| 
 | |
|   /* Check if the minimum_size and natural_size is already
 | |
|    * in the cache and if this result can be used to extend
 | |
|    * that cache entry 
 | |
|    */
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     {
 | |
|       cached_sizes = cache->widths;
 | |
|       n_sizes = cache->cached_widths;
 | |
|     }
 | |
|   else
 | |
|     {
 | |
|       cached_sizes = cache->heights;
 | |
|       n_sizes = cache->cached_heights;
 | |
|     }
 | |
| 
 | |
|   for (i = 0; i < n_sizes; i++)
 | |
|     {
 | |
|       if (cached_sizes[i]->cached_size.minimum_size == minimum_size &&
 | |
| 	  cached_sizes[i]->cached_size.natural_size == natural_size)
 | |
| 	{
 | |
| 	  cached_sizes[i]->lower_for_size = MIN (cached_sizes[i]->lower_for_size, for_size);
 | |
| 	  cached_sizes[i]->upper_for_size = MAX (cached_sizes[i]->upper_for_size, for_size);
 | |
| 	  return;
 | |
| 	}
 | |
|     }
 | |
| 
 | |
|   /* If not found, pull a new size from the cache, the returned size cache
 | |
|    * will immediately be used to cache the new computed size so we go ahead
 | |
|    * and increment the last_cached_width/height right away */
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     {
 | |
|       if (cache->cached_widths < GTK_SIZE_REQUEST_CACHED_SIZES)
 | |
| 	{
 | |
| 	  cache->cached_widths++;
 | |
| 	  cache->last_cached_width = cache->cached_widths - 1;
 | |
| 	}
 | |
|       else
 | |
| 	{
 | |
| 	  if (++cache->last_cached_width == GTK_SIZE_REQUEST_CACHED_SIZES)
 | |
| 	    cache->last_cached_width = 0;
 | |
| 	}
 | |
| 
 | |
|       if (!cache->widths)
 | |
| 	cache->widths = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
 | |
| 
 | |
|       if (!cache->widths[cache->last_cached_width])
 | |
| 	cache->widths[cache->last_cached_width] = g_slice_new (SizeRequest);
 | |
| 
 | |
|       cache->widths[cache->last_cached_width]->lower_for_size = for_size;
 | |
|       cache->widths[cache->last_cached_width]->upper_for_size = for_size;
 | |
|       cache->widths[cache->last_cached_width]->cached_size.minimum_size = minimum_size;
 | |
|       cache->widths[cache->last_cached_width]->cached_size.natural_size = natural_size;
 | |
|     }
 | |
|   else /* GTK_SIZE_GROUP_VERTICAL */
 | |
|     {
 | |
|       if (cache->cached_heights < GTK_SIZE_REQUEST_CACHED_SIZES)
 | |
| 	{
 | |
| 	  cache->cached_heights++;
 | |
| 	  cache->last_cached_height = cache->cached_heights - 1;
 | |
| 	}
 | |
|       else
 | |
| 	{
 | |
| 	  if (++cache->last_cached_height == GTK_SIZE_REQUEST_CACHED_SIZES)
 | |
| 	    cache->last_cached_height = 0;
 | |
| 	}
 | |
| 
 | |
|       if (!cache->heights)
 | |
| 	cache->heights = g_slice_alloc0 (sizeof (SizeRequest *) * GTK_SIZE_REQUEST_CACHED_SIZES);
 | |
| 
 | |
|       if (!cache->heights[cache->last_cached_height])
 | |
| 	cache->heights[cache->last_cached_height] = g_slice_new (SizeRequest);
 | |
| 
 | |
|       cache->heights[cache->last_cached_height]->lower_for_size = for_size;
 | |
|       cache->heights[cache->last_cached_height]->upper_for_size = for_size;
 | |
|       cache->heights[cache->last_cached_height]->cached_size.minimum_size = minimum_size;
 | |
|       cache->heights[cache->last_cached_height]->cached_size.natural_size = natural_size;
 | |
|     }
 | |
| }
 | |
| 
 | |
| static const char *
 | |
| get_vfunc_name (GtkSizeGroupMode orientation,
 | |
|                 gint             for_size)
 | |
| {
 | |
|   if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|     return for_size < 0 ? "get_preferred_width" : "get_preferred_width_for_height";
 | |
|   else
 | |
|     return for_size < 0 ? "get_preferred_height" : "get_preferred_height_for_width";
 | |
| }
 | |
| 
 | |
| /* This is the main function that checks for a cached size and
 | |
|  * possibly queries the widget class to compute the size if it's
 | |
|  * not cached. If the for_size here is -1, then get_preferred_width()
 | |
|  * or get_preferred_height() will be used.
 | |
|  */
 | |
| static void
 | |
| compute_size_for_orientation (GtkWidget         *widget,
 | |
|                               GtkSizeGroupMode   orientation,
 | |
|                               gint               for_size,
 | |
|                               gint              *minimum_size,
 | |
|                               gint              *natural_size)
 | |
| {
 | |
|   CachedSize       *cached_size;
 | |
|   gboolean          found_in_cache = FALSE;
 | |
|   gint              min_size = 0;
 | |
|   gint              nat_size = 0;
 | |
| 
 | |
|   found_in_cache = get_cached_size (widget, orientation, for_size, &cached_size);
 | |
| 
 | |
|   if (!found_in_cache)
 | |
|     {
 | |
|       gint adjusted_min, adjusted_natural, adjusted_for_size = for_size;
 | |
| 
 | |
|       gtk_widget_ensure_style (widget);
 | |
| 
 | |
|       if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|         {
 | |
|           if (for_size < 0)
 | |
|             {
 | |
| 	      push_recursion_check (widget, orientation, for_size);
 | |
|               GTK_WIDGET_GET_CLASS (widget)->get_preferred_width (widget, &min_size, &nat_size);
 | |
| 	      pop_recursion_check (widget, orientation);
 | |
|             }
 | |
|           else
 | |
|             {
 | |
|               gint ignored_position = 0;
 | |
|               gint minimum_height;
 | |
|               gint natural_height;
 | |
| 
 | |
| 	      /* Pull the base natural height from the cache as it's needed to adjust
 | |
| 	       * the proposed 'for_size' */
 | |
| 	      gtk_widget_get_preferred_height (widget, &minimum_height, &natural_height);
 | |
| 
 | |
|               /* convert for_size to unadjusted height (for_size is a proposed allocation) */
 | |
|               GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
 | |
|                                                                      GTK_ORIENTATION_VERTICAL,
 | |
|                                                                      &minimum_height,
 | |
| 								     &natural_height,
 | |
|                                                                      &ignored_position,
 | |
|                                                                      &adjusted_for_size);
 | |
| 
 | |
| 	      push_recursion_check (widget, orientation, for_size);
 | |
|               GTK_WIDGET_GET_CLASS (widget)->get_preferred_width_for_height (widget, 
 | |
| 									     MAX (adjusted_for_size, minimum_height),
 | |
| 									     &min_size, &nat_size);
 | |
| 	      pop_recursion_check (widget, orientation);
 | |
|             }
 | |
|         }
 | |
|       else
 | |
|         {
 | |
|           if (for_size < 0)
 | |
|             {
 | |
| 	      push_recursion_check (widget, orientation, for_size);
 | |
|               GTK_WIDGET_GET_CLASS (widget)->get_preferred_height (widget, &min_size, &nat_size);
 | |
| 	      pop_recursion_check (widget, orientation);
 | |
|             }
 | |
|           else
 | |
|             {
 | |
|               gint ignored_position = 0;
 | |
|               gint minimum_width;
 | |
|               gint natural_width;
 | |
| 
 | |
| 	      /* Pull the base natural width from the cache as it's needed to adjust
 | |
| 	       * the proposed 'for_size' */
 | |
| 	      gtk_widget_get_preferred_width (widget, &minimum_width, &natural_width);
 | |
| 
 | |
|               /* convert for_size to unadjusted width (for_size is a proposed allocation) */
 | |
|               GTK_WIDGET_GET_CLASS (widget)->adjust_size_allocation (widget,
 | |
|                                                                      GTK_ORIENTATION_HORIZONTAL,
 | |
| 								     &minimum_width,
 | |
|                                                                      &natural_width,
 | |
|                                                                      &ignored_position,
 | |
|                                                                      &adjusted_for_size);
 | |
| 
 | |
| 	      push_recursion_check (widget, orientation, for_size);
 | |
|               GTK_WIDGET_GET_CLASS (widget)->get_preferred_height_for_width (widget, 
 | |
| 									     MAX (adjusted_for_size, minimum_width),
 | |
| 									     &min_size, &nat_size);
 | |
| 	      pop_recursion_check (widget, orientation);
 | |
|             }
 | |
|         }
 | |
| 
 | |
|       if (min_size > nat_size)
 | |
|         {
 | |
|           g_warning ("%s %p reported min size %d and natural size %d in %s(); natural size must be >= min size",
 | |
|                      G_OBJECT_TYPE_NAME (widget), widget, min_size, nat_size, get_vfunc_name (orientation, for_size));
 | |
|         }
 | |
| 
 | |
|       if (orientation == GTK_SIZE_GROUP_HORIZONTAL)
 | |
|           _gtk_widget_set_width_request_needed (widget, FALSE);
 | |
|       else
 | |
|           _gtk_widget_set_height_request_needed (widget, FALSE);
 | |
| 
 | |
|       adjusted_min     = min_size;
 | |
|       adjusted_natural = nat_size;
 | |
|       GTK_WIDGET_GET_CLASS (widget)->adjust_size_request (widget,
 | |
|                                                           orientation == GTK_SIZE_GROUP_HORIZONTAL ?
 | |
|                                                           GTK_ORIENTATION_HORIZONTAL :
 | |
|                                                           GTK_ORIENTATION_VERTICAL,
 | |
|                                                           &adjusted_min,
 | |
|                                                           &adjusted_natural);
 | |
| 
 | |
|       if (adjusted_min < min_size ||
 | |
|           adjusted_natural < nat_size)
 | |
|         {
 | |
|           g_warning ("%s %p adjusted size %s min %d natural %d must not decrease below min %d natural %d",
 | |
|                      G_OBJECT_TYPE_NAME (widget), widget,
 | |
|                      orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
 | |
|                      adjusted_min, adjusted_natural,
 | |
|                      min_size, nat_size);
 | |
|           /* don't use the adjustment */
 | |
|         }
 | |
|       else if (adjusted_min > adjusted_natural)
 | |
|         {
 | |
|           g_warning ("%s %p adjusted size %s min %d natural %d original min %d natural %d has min greater than natural",
 | |
|                      G_OBJECT_TYPE_NAME (widget), widget,
 | |
|                      orientation == GTK_SIZE_GROUP_VERTICAL ? "vertical" : "horizontal",
 | |
|                      adjusted_min, adjusted_natural,
 | |
|                      min_size, nat_size);
 | |
|           /* don't use the adjustment */
 | |
|         }
 | |
|       else
 | |
|         {
 | |
|           /* adjustment looks good */
 | |
|           min_size = adjusted_min;
 | |
|           nat_size = adjusted_natural;
 | |
|         }
 | |
| 
 | |
|       /* Update size-groups with our request and update our cached requests
 | |
|        * with the size-group values in a single pass.
 | |
|        */
 | |
|       _gtk_size_group_bump_requisition (widget,
 | |
| 					orientation,
 | |
| 					&min_size,
 | |
| 					&nat_size);
 | |
| 
 | |
|       commit_cached_size (widget, orientation, for_size, min_size, nat_size);
 | |
|     }
 | |
|   else
 | |
|     {
 | |
|       min_size = cached_size->minimum_size;
 | |
|       nat_size = cached_size->natural_size;
 | |
|     }
 | |
| 
 | |
|   if (minimum_size)
 | |
|     *minimum_size = min_size;
 | |
| 
 | |
|   if (natural_size)
 | |
|     *natural_size = nat_size;
 | |
| 
 | |
|   g_assert (min_size <= nat_size);
 | |
| 
 | |
|   GTK_NOTE (SIZE_REQUEST,
 | |
|             g_print ("[%p] %s\t%s: %d is minimum %d and natural: %d (hit cache: %s)\n",
 | |
|                      widget, G_OBJECT_TYPE_NAME (widget),
 | |
|                      orientation == GTK_SIZE_GROUP_HORIZONTAL ?
 | |
|                      "width for height" : "height for width" ,
 | |
|                      for_size, min_size, nat_size,
 | |
|                      found_in_cache ? "yes" : "no"));
 | |
| 
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_request_mode:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  *
 | |
|  * Gets whether the widget prefers a height-for-width layout
 | |
|  * or a width-for-height layout.
 | |
|  *
 | |
|  * <note><para>#GtkBin widgets generally propagate the preference of
 | |
|  * their child, container widgets need to request something either in
 | |
|  * context of their children or in context of their allocation
 | |
|  * capabilities.</para></note>
 | |
|  *
 | |
|  * Returns: The #GtkSizeRequestMode preferred by @widget.
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| GtkSizeRequestMode
 | |
| gtk_widget_get_request_mode (GtkWidget *widget)
 | |
| {
 | |
|   g_return_val_if_fail (GTK_IS_WIDGET (widget), GTK_SIZE_REQUEST_CONSTANT_SIZE);
 | |
| 
 | |
|   return GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_preferred_width:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  * @minimum_width: (out) (allow-none): location to store the minimum width, or %NULL
 | |
|  * @natural_width: (out) (allow-none): location to store the natural width, or %NULL
 | |
|  *
 | |
|  * Retrieves a widget's initial minimum and natural width.
 | |
|  *
 | |
|  * <note><para>This call is specific to height-for-width
 | |
|  * requests.</para></note>
 | |
|  *
 | |
|  * The returned request will be modified by the
 | |
|  * GtkWidgetClass::adjust_size_request virtual method and by any
 | |
|  * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
 | |
|  * is the one that should be used for layout, not necessarily the one
 | |
|  * returned by the widget itself.
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| void
 | |
| gtk_widget_get_preferred_width (GtkWidget *widget,
 | |
|                                 gint      *minimum_width,
 | |
|                                 gint      *natural_width)
 | |
| {
 | |
|   g_return_if_fail (GTK_IS_WIDGET (widget));
 | |
|   g_return_if_fail (minimum_width != NULL || natural_width != NULL);
 | |
| 
 | |
|   compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
 | |
|                                 -1, minimum_width, natural_width);
 | |
| }
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_preferred_height:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  * @minimum_height: (out) (allow-none): location to store the minimum height, or %NULL
 | |
|  * @natural_height: (out) (allow-none): location to store the natural height, or %NULL
 | |
|  *
 | |
|  * Retrieves a widget's initial minimum and natural height.
 | |
|  *
 | |
|  * <note><para>This call is specific to width-for-height requests.</para></note>
 | |
|  *
 | |
|  * The returned request will be modified by the
 | |
|  * GtkWidgetClass::adjust_size_request virtual method and by any
 | |
|  * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
 | |
|  * is the one that should be used for layout, not necessarily the one
 | |
|  * returned by the widget itself.
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| void
 | |
| gtk_widget_get_preferred_height (GtkWidget *widget,
 | |
|                                  gint      *minimum_height,
 | |
|                                  gint      *natural_height)
 | |
| {
 | |
|   g_return_if_fail (GTK_IS_WIDGET (widget));
 | |
|   g_return_if_fail (minimum_height != NULL || natural_height != NULL);
 | |
| 
 | |
|   compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
 | |
|                                 -1, minimum_height, natural_height);
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_preferred_width_for_height:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  * @height: the height which is available for allocation
 | |
|  * @minimum_width: (out) (allow-none): location for storing the minimum width, or %NULL
 | |
|  * @natural_width: (out) (allow-none): location for storing the natural width, or %NULL
 | |
|  *
 | |
|  * Retrieves a widget's minimum and natural width if it would be given
 | |
|  * the specified @height.
 | |
|  *
 | |
|  * The returned request will be modified by the
 | |
|  * GtkWidgetClass::adjust_size_request virtual method and by any
 | |
|  * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
 | |
|  * is the one that should be used for layout, not necessarily the one
 | |
|  * returned by the widget itself.
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| void
 | |
| gtk_widget_get_preferred_width_for_height (GtkWidget *widget,
 | |
|                                            gint       height,
 | |
|                                            gint      *minimum_width,
 | |
|                                            gint      *natural_width)
 | |
| {
 | |
|   g_return_if_fail (GTK_IS_WIDGET (widget));
 | |
|   g_return_if_fail (minimum_width != NULL || natural_width != NULL);
 | |
|   g_return_if_fail (height >= 0);
 | |
| 
 | |
|   if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
 | |
|     compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
 | |
| 				  -1, minimum_width, natural_width);
 | |
|   else
 | |
|     compute_size_for_orientation (widget, GTK_SIZE_GROUP_HORIZONTAL,
 | |
| 				  height, minimum_width, natural_width);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_preferred_height_for_width:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  * @width: the width which is available for allocation
 | |
|  * @minimum_height: (out) (allow-none): location for storing the minimum height, or %NULL
 | |
|  * @natural_height: (out) (allow-none): location for storing the natural height, or %NULL
 | |
|  *
 | |
|  * Retrieves a widget's minimum and natural height if it would be given
 | |
|  * the specified @width.
 | |
|  *
 | |
|  * The returned request will be modified by the
 | |
|  * GtkWidgetClass::adjust_size_request virtual method and by any
 | |
|  * #GtkSizeGroup<!-- -->s that have been applied. That is, the returned request
 | |
|  * is the one that should be used for layout, not necessarily the one
 | |
|  * returned by the widget itself.
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| void
 | |
| gtk_widget_get_preferred_height_for_width (GtkWidget *widget,
 | |
|                                            gint       width,
 | |
|                                            gint      *minimum_height,
 | |
|                                            gint      *natural_height)
 | |
| {
 | |
|   g_return_if_fail (GTK_IS_WIDGET (widget));
 | |
|   g_return_if_fail (minimum_height != NULL || natural_height != NULL);
 | |
|   g_return_if_fail (width >= 0);
 | |
| 
 | |
|   if (GTK_WIDGET_GET_CLASS (widget)->get_request_mode (widget) == GTK_SIZE_REQUEST_CONSTANT_SIZE)
 | |
|     compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
 | |
| 				  -1, minimum_height, natural_height);
 | |
|   else
 | |
|     compute_size_for_orientation (widget, GTK_SIZE_GROUP_VERTICAL,
 | |
| 				  width, minimum_height, natural_height);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * gtk_widget_get_preferred_size:
 | |
|  * @widget: a #GtkWidget instance
 | |
|  * @minimum_size: (out) (allow-none): location for storing the minimum size, or %NULL
 | |
|  * @natural_size: (out) (allow-none): location for storing the natural size, or %NULL
 | |
|  *
 | |
|  * Retrieves the minimum and natural size of a widget, taking
 | |
|  * into account the widget's preference for height-for-width management.
 | |
|  *
 | |
|  * This is used to retrieve a suitable size by container widgets which do
 | |
|  * not impose any restrictions on the child placement. It can be used
 | |
|  * to deduce toplevel window and menu sizes as well as child widgets in
 | |
|  * free-form containers such as GtkLayout.
 | |
|  *
 | |
|  * <note><para>Handle with care. Note that the natural height of a height-for-width
 | |
|  * widget will generally be a smaller size than the minimum height, since the required
 | |
|  * height for the natural width is generally smaller than the required height for
 | |
|  * the minimum width.</para></note>
 | |
|  *
 | |
|  * Since: 3.0
 | |
|  */
 | |
| void
 | |
| gtk_widget_get_preferred_size (GtkWidget      *widget,
 | |
|                                GtkRequisition *minimum_size,
 | |
|                                GtkRequisition *natural_size)
 | |
| {
 | |
|   gint min_width, nat_width;
 | |
|   gint min_height, nat_height;
 | |
| 
 | |
|   g_return_if_fail (GTK_IS_WIDGET (widget));
 | |
| 
 | |
|   if (gtk_widget_get_request_mode (widget) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
 | |
|     {
 | |
|       gtk_widget_get_preferred_width (widget, &min_width, &nat_width);
 | |
| 
 | |
|       if (minimum_size)
 | |
| 	{
 | |
| 	  minimum_size->width = min_width;
 | |
| 	  gtk_widget_get_preferred_height_for_width (widget, min_width,
 | |
|                                                      &minimum_size->height, NULL);
 | |
| 	}
 | |
| 
 | |
|       if (natural_size)
 | |
| 	{
 | |
| 	  natural_size->width = nat_width;
 | |
| 	  gtk_widget_get_preferred_height_for_width (widget, nat_width,
 | |
|                                                      NULL, &natural_size->height);
 | |
| 	}
 | |
|     }
 | |
|   else /* GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT or CONSTANT_SIZE */
 | |
|     {
 | |
|       gtk_widget_get_preferred_height (widget, &min_height, &nat_height);
 | |
| 
 | |
|       if (minimum_size)
 | |
| 	{
 | |
| 	  minimum_size->height = min_height;
 | |
| 	  gtk_widget_get_preferred_width_for_height (widget, min_height,
 | |
|                                                      &minimum_size->width, NULL);
 | |
| 	}
 | |
| 
 | |
|       if (natural_size)
 | |
| 	{
 | |
| 	  natural_size->height = nat_height;
 | |
| 	  gtk_widget_get_preferred_width_for_height (widget, nat_height,
 | |
|                                                      NULL, &natural_size->width);
 | |
| 	}
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| static gint
 | |
| compare_gap (gconstpointer p1,
 | |
| 	     gconstpointer p2,
 | |
| 	     gpointer      data)
 | |
| {
 | |
|   GtkRequestedSize *sizes = data;
 | |
|   const guint *c1 = p1;
 | |
|   const guint *c2 = p2;
 | |
| 
 | |
|   const gint d1 = MAX (sizes[*c1].natural_size -
 | |
|                        sizes[*c1].minimum_size,
 | |
|                        0);
 | |
|   const gint d2 = MAX (sizes[*c2].natural_size -
 | |
|                        sizes[*c2].minimum_size,
 | |
|                        0);
 | |
| 
 | |
|   gint delta = (d2 - d1);
 | |
| 
 | |
|   if (0 == delta)
 | |
|     delta = (*c2 - *c1);
 | |
| 
 | |
|   return delta;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * gtk_distribute_natural_allocation:
 | |
|  * @extra_space: Extra space to redistribute among children after subtracting
 | |
|  *               minimum sizes and any child padding from the overall allocation
 | |
|  * @n_requested_sizes: Number of requests to fit into the allocation
 | |
|  * @sizes: An array of structs with a client pointer and a minimum/natural size
 | |
|  *         in the orientation of the allocation.
 | |
|  *
 | |
|  * Distributes @extra_space to child @sizes by bringing smaller
 | |
|  * children up to natural size first.
 | |
|  *
 | |
|  * The remaining space will be added to the @minimum_size member of the
 | |
|  * GtkRequestedSize struct. If all sizes reach their natural size then
 | |
|  * the remaining space is returned.
 | |
|  *
 | |
|  * Returns: The remainder of @extra_space after redistributing space
 | |
|  * to @sizes.
 | |
|  */
 | |
| gint
 | |
| gtk_distribute_natural_allocation (gint              extra_space,
 | |
| 				   guint             n_requested_sizes,
 | |
| 				   GtkRequestedSize *sizes)
 | |
| {
 | |
|   guint *spreading;
 | |
|   gint   i;
 | |
| 
 | |
|   g_return_val_if_fail (extra_space >= 0, 0);
 | |
| 
 | |
|   spreading = g_newa (guint, n_requested_sizes);
 | |
| 
 | |
|   for (i = 0; i < n_requested_sizes; i++)
 | |
|     spreading[i] = i;
 | |
| 
 | |
|   /* Distribute the container's extra space c_gap. We want to assign
 | |
|    * this space such that the sum of extra space assigned to children
 | |
|    * (c^i_gap) is equal to c_cap. The case that there's not enough
 | |
|    * space for all children to take their natural size needs some
 | |
|    * attention. The goals we want to achieve are:
 | |
|    *
 | |
|    *   a) Maximize number of children taking their natural size.
 | |
|    *   b) The allocated size of children should be a continuous
 | |
|    *   function of c_gap.  That is, increasing the container size by
 | |
|    *   one pixel should never make drastic changes in the distribution.
 | |
|    *   c) If child i takes its natural size and child j doesn't,
 | |
|    *   child j should have received at least as much gap as child i.
 | |
|    *
 | |
|    * The following code distributes the additional space by following
 | |
|    * these rules.
 | |
|    */
 | |
| 
 | |
|   /* Sort descending by gap and position. */
 | |
|   g_qsort_with_data (spreading,
 | |
| 		     n_requested_sizes, sizeof (guint),
 | |
| 		     compare_gap, sizes);
 | |
| 
 | |
|   /* Distribute available space.
 | |
|    * This master piece of a loop was conceived by Behdad Esfahbod.
 | |
|    */
 | |
|   for (i = n_requested_sizes - 1; extra_space > 0 && i >= 0; --i)
 | |
|     {
 | |
|       /* Divide remaining space by number of remaining children.
 | |
|        * Sort order and reducing remaining space by assigned space
 | |
|        * ensures that space is distributed equally.
 | |
|        */
 | |
|       gint glue = (extra_space + i) / (i + 1);
 | |
|       gint gap = sizes[(spreading[i])].natural_size
 | |
| 	- sizes[(spreading[i])].minimum_size;
 | |
| 
 | |
|       gint extra = MIN (glue, gap);
 | |
| 
 | |
|       sizes[spreading[i]].minimum_size += extra;
 | |
| 
 | |
|       extra_space -= extra;
 | |
|     }
 | |
| 
 | |
|   return extra_space;
 | |
| }
 | 
