Pileus Git - ~andy/gtk/blob - gtk/gtkbbox.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GTK+ Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 /**
  28  * SECTION:gtkbbox
  29  * @Short_description: Base class for GtkHButtonBox and GtkVButtonBox
  30  * @Title: GtkButtonBox
  31  * @See_also: #GtkVButtonBox, #GtkHButtonBox
  32  *
  33  * The primary purpose of this class is to keep track of the various
  34  * properties of #GtkHButtonBox and #GtkVButtonBox widgets.
  35  *
  36  * gtk_button_box_get_layout() and gtk_button_box_set_layout() retrieve and
  37  * alter the method used to spread the buttons in a button box across the
  38  * container, respectively.
  39  *
  40  * The main purpose of GtkButtonBox is to make sure the children have all the
  41  * same size. GtkButtonBox gives all children the same size, but it does allow
  42  * 'outliers' to keep their own larger size. To force all children to be
  43  * strictly the same size without exceptions, you can set the
  44  * #GtkButtonBox::homogeneous property to %TRUE.
  45  */
  46
  47 #include "config.h"
  48
  49 #include "gtkbbox.h"
  50
  51 #include "gtkorientable.h"
  52 #include "gtktypebuiltins.h"
  53 #include "gtkprivate.h"
  54 #include "gtksizerequest.h"
  55
  56 #include "gtkintl.h"
  57
  58
  59 struct _GtkButtonBoxPrivate
  60 {
  61   GtkButtonBoxStyle layout_style;
  62 };
  63
  64 enum {
  65   PROP_0,
  66   PROP_LAYOUT_STYLE
  67 };
  68
  69 enum {
  70   CHILD_PROP_0,
  71   CHILD_PROP_SECONDARY
  72 };
  73
  74 #define GTK_BOX_SECONDARY_CHILD "gtk-box-secondary-child"
  75
  76 static void gtk_button_box_set_property       (GObject           *object,
  77                                                guint              prop_id,
  78                                                const GValue      *value,
  79                                                GParamSpec        *pspec);
  80 static void gtk_button_box_get_property       (GObject           *object,
  81                                                guint              prop_id,
  82                                                GValue            *value,
  83                                                GParamSpec        *pspec);
  84 static void gtk_button_box_get_preferred_width            (GtkWidget *widget,
  85                                                            gint      *minimum,
  86                                                            gint      *natural);
  87 static void gtk_button_box_get_preferred_height           (GtkWidget *widget,
  88                                                            gint      *minimum,
  89                                                            gint      *natural);
  90 static void gtk_button_box_get_preferred_width_for_height (GtkWidget *widget,
  91                                                            gint       height,
  92                                                            gint      *minimum,
  93                                                            gint      *natural);
  94 static void gtk_button_box_get_preferred_height_for_width (GtkWidget *widget,
  95                                                            gint       width,
  96                                                            gint      *minimum,
  97                                                            gint      *natural);
  98
  99 static void gtk_button_box_size_allocate      (GtkWidget         *widget,
 100                                                GtkAllocation     *allocation);
 101 static void gtk_button_box_remove             (GtkContainer      *container,
 102                                                GtkWidget         *widget);
 103 static void gtk_button_box_set_child_property (GtkContainer      *container,
 104                                                GtkWidget         *child,
 105                                                guint              property_id,
 106                                                const GValue      *value,
 107                                                GParamSpec        *pspec);
 108 static void gtk_button_box_get_child_property (GtkContainer      *container,
 109                                                GtkWidget         *child,
 110                                                guint              property_id,
 111                                                GValue            *value,
 112                                                GParamSpec        *pspec);
 113
 114 #define DEFAULT_CHILD_MIN_WIDTH 85
 115 #define DEFAULT_CHILD_MIN_HEIGHT 27
 116 #define DEFAULT_CHILD_IPAD_X 4
 117 #define DEFAULT_CHILD_IPAD_Y 0
 118 #define DEFAULT_LAYOUT_STYLE GTK_BUTTONBOX_EDGE
 119
 120 G_DEFINE_TYPE (GtkButtonBox, gtk_button_box, GTK_TYPE_BOX)
 121
 122 static void
 123 gtk_button_box_class_init (GtkButtonBoxClass *class)
 124 {
 125   GtkWidgetClass *widget_class;
 126   GObjectClass *gobject_class;
 127   GtkContainerClass *container_class;
 128
 129   gobject_class = G_OBJECT_CLASS (class);
 130   widget_class = (GtkWidgetClass*) class;
 131   container_class = (GtkContainerClass*) class;
 132
 133   gobject_class->set_property = gtk_button_box_set_property;
 134   gobject_class->get_property = gtk_button_box_get_property;
 135
 136   widget_class->get_preferred_width = gtk_button_box_get_preferred_width;
 137   widget_class->get_preferred_height = gtk_button_box_get_preferred_height;
 138   widget_class->get_preferred_width_for_height = gtk_button_box_get_preferred_width_for_height;
 139   widget_class->get_preferred_height_for_width = gtk_button_box_get_preferred_height_for_width;
 140   widget_class->size_allocate = gtk_button_box_size_allocate;
 141
 142   container_class->remove = gtk_button_box_remove;
 143   container_class->set_child_property = gtk_button_box_set_child_property;
 144   container_class->get_child_property = gtk_button_box_get_child_property;
 145   gtk_container_class_handle_border_width (container_class);
 146
 147   /* FIXME we need to override the "spacing" property on GtkBox once
 148    * libgobject allows that.
 149    */
 150   gtk_widget_class_install_style_property (widget_class,
 151                                            g_param_spec_int ("child-min-width",
 152                                                              P_("Minimum child width"),
 153                                                              P_("Minimum width of buttons inside the box"),
 154                                                              0,
 155                                                              G_MAXINT,
 156                                                              DEFAULT_CHILD_MIN_WIDTH,
 157                                                              GTK_PARAM_READABLE));
 158
 159   gtk_widget_class_install_style_property (widget_class,
 160                                            g_param_spec_int ("child-min-height",
 161                                                              P_("Minimum child height"),
 162                                                              P_("Minimum height of buttons inside the box"),
 163                                                              0,
 164                                                              G_MAXINT,
 165                                                              DEFAULT_CHILD_MIN_HEIGHT,
 166                                                              GTK_PARAM_READABLE));
 167
 168   gtk_widget_class_install_style_property (widget_class,
 169                                            g_param_spec_int ("child-internal-pad-x",
 170                                                              P_("Child internal width padding"),
 171                                                              P_("Amount to increase child's size on either side"),
 172                                                              0,
 173                                                              G_MAXINT,
 174                                                              DEFAULT_CHILD_IPAD_X,
 175                                                              GTK_PARAM_READABLE));
 176
 177   gtk_widget_class_install_style_property (widget_class,
 178                                            g_param_spec_int ("child-internal-pad-y",
 179                                                              P_("Child internal height padding"),
 180                                                              P_("Amount to increase child's size on the top and bottom"),
 181                                                              0,
 182                                                              G_MAXINT,
 183                                                              DEFAULT_CHILD_IPAD_Y,
 184                                                              GTK_PARAM_READABLE));
 185   g_object_class_install_property (gobject_class,
 186                                    PROP_LAYOUT_STYLE,
 187                                    g_param_spec_enum ("layout-style",
 188                                                       P_("Layout style"),
 189                                                       P_("How to lay out the buttons in the box. Possible values are: spread, edge, start and end"),
 190                                                       GTK_TYPE_BUTTON_BOX_STYLE,
 191                                                       DEFAULT_LAYOUT_STYLE,
 192                                                       GTK_PARAM_READWRITE));
 193
 194   gtk_container_class_install_child_property (container_class,
 195                                               CHILD_PROP_SECONDARY,
 196                                               g_param_spec_boolean ("secondary",
 197                                                                     P_("Secondary"),
 198                                                                     P_("If TRUE, the child appears in a secondary group of children, suitable for, e.g., help buttons"),
 199                                                                     FALSE,
 200                                                                     GTK_PARAM_READWRITE));
 201
 202   g_type_class_add_private (class, sizeof (GtkButtonBoxPrivate));
 203 }
 204
 205 static void
 206 gtk_button_box_init (GtkButtonBox *button_box)
 207 {
 208   GtkButtonBoxPrivate *priv;
 209
 210   button_box->priv = G_TYPE_INSTANCE_GET_PRIVATE (button_box,
 211                                                   GTK_TYPE_BUTTON_BOX,
 212                                                   GtkButtonBoxPrivate);
 213   priv = button_box->priv;
 214
 215   gtk_box_set_spacing (GTK_BOX (button_box), 0);
 216   priv->layout_style = DEFAULT_LAYOUT_STYLE;
 217 }
 218
 219 static void
 220 gtk_button_box_set_property (GObject      *object,
 221                              guint         prop_id,
 222                              const GValue *value,
 223                              GParamSpec   *pspec)
 224 {
 225   switch (prop_id)
 226     {
 227     case PROP_LAYOUT_STYLE:
 228       gtk_button_box_set_layout (GTK_BUTTON_BOX (object),
 229                                  g_value_get_enum (value));
 230       break;
 231     default:
 232       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 233       break;
 234     }
 235 }
 236
 237 static void
 238 gtk_button_box_get_property (GObject    *object,
 239                              guint       prop_id,
 240                              GValue     *value,
 241                              GParamSpec *pspec)
 242 {
 243   GtkButtonBoxPrivate *priv = GTK_BUTTON_BOX (object)->priv;
 244
 245   switch (prop_id)
 246     {
 247     case PROP_LAYOUT_STYLE:
 248       g_value_set_enum (value, priv->layout_style);
 249       break;
 250     default:
 251       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 252       break;
 253     }
 254 }
 255
 256 static void
 257 gtk_button_box_set_child_property (GtkContainer *container,
 258                                    GtkWidget    *child,
 259                                    guint         property_id,
 260                                    const GValue *value,
 261                                    GParamSpec   *pspec)
 262 {
 263   switch (property_id)
 264     {
 265     case CHILD_PROP_SECONDARY:
 266       gtk_button_box_set_child_secondary (GTK_BUTTON_BOX (container), child,
 267                                           g_value_get_boolean (value));
 268       break;
 269     default:
 270       GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
 271       break;
 272     }
 273 }
 274
 275 static void
 276 gtk_button_box_get_child_property (GtkContainer *container,
 277                                    GtkWidget    *child,
 278                                    guint         property_id,
 279                                    GValue       *value,
 280                                    GParamSpec   *pspec)
 281 {
 282   switch (property_id)
 283     {
 284     case CHILD_PROP_SECONDARY:
 285       g_value_set_boolean (value,
 286                            gtk_button_box_get_child_secondary (GTK_BUTTON_BOX (container),
 287                                                                child));
 288       break;
 289     default:
 290       GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID (container, property_id, pspec);
 291       break;
 292     }
 293 }
 294
 295 static void
 296 gtk_button_box_remove (GtkContainer *container,
 297                        GtkWidget    *widget)
 298 {
 299   /* clear is_secondary flag in case the widget
 300    * is added to another container
 301    */
 302   gtk_button_box_set_child_secondary (GTK_BUTTON_BOX (container),
 303                                       widget,
 304                                       FALSE);
 305
 306   GTK_CONTAINER_CLASS (gtk_button_box_parent_class)->remove (container, widget);
 307 }
 308
 309 /**
 310  * gtk_button_box_set_layout:
 311  * @widget: a #GtkButtonBox
 312  * @layout_style: the new layout style
 313  *
 314  * Changes the way buttons are arranged in their container.
 315  */
 316 void
 317 gtk_button_box_set_layout (GtkButtonBox      *widget,
 318                            GtkButtonBoxStyle  layout_style)
 319 {
 320   GtkButtonBoxPrivate *priv;
 321
 322   g_return_if_fail (GTK_IS_BUTTON_BOX (widget));
 323
 324   priv = widget->priv;
 325
 326   if (priv->layout_style != layout_style)
 327     {
 328       priv->layout_style = layout_style;
 329       g_object_notify (G_OBJECT (widget), "layout-style");
 330       gtk_widget_queue_resize (GTK_WIDGET (widget));
 331     }
 332 }
 333
 334 /**
 335  * gtk_button_box_get_layout:
 336  * @widget: a #GtkButtonBox
 337  *
 338  * Retrieves the method being used to arrange the buttons in a button box.
 339  *
 340  * Returns: the method used to lay out buttons in @widget.
 341  */
 342 GtkButtonBoxStyle
 343 gtk_button_box_get_layout (GtkButtonBox *widget)
 344 {
 345   g_return_val_if_fail (GTK_IS_BUTTON_BOX (widget), DEFAULT_LAYOUT_STYLE);
 346
 347   return widget->priv->layout_style;
 348 }
 349
 350 /**
 351  * gtk_button_box_get_child_secondary:
 352  * @widget: a #GtkButtonBox
 353  * @child: a child of @widget
 354  *
 355  * Returns whether @child should appear in a secondary group of children.
 356  *
 357  * Return value: whether @child should appear in a secondary group of children.
 358  *
 359  * Since: 2.4
 360  **/
 361 gboolean
 362 gtk_button_box_get_child_secondary (GtkButtonBox *widget,
 363                                     GtkWidget    *child)
 364 {
 365   g_return_val_if_fail (GTK_IS_BUTTON_BOX (widget), FALSE);
 366   g_return_val_if_fail (GTK_IS_WIDGET (child), FALSE);
 367
 368   return (g_object_get_data (G_OBJECT (child), GTK_BOX_SECONDARY_CHILD) != NULL);
 369 }
 370
 371 /**
 372  * gtk_button_box_set_child_secondary
 373  * @widget: a #GtkButtonBox
 374  * @child: a child of @widget
 375  * @is_secondary: if %TRUE, the @child appears in a secondary group of the
 376  *                button box.
 377  *
 378  * Sets whether @child should appear in a secondary group of children.
 379  * A typical use of a secondary child is the help button in a dialog.
 380  *
 381  * This group appears after the other children if the style
 382  * is %GTK_BUTTONBOX_START, %GTK_BUTTONBOX_SPREAD or
 383  * %GTK_BUTTONBOX_EDGE, and before the other children if the style
 384  * is %GTK_BUTTONBOX_END. For horizontal button boxes, the definition
 385  * of before/after depends on direction of the widget (see
 386  * gtk_widget_set_direction()). If the style is %GTK_BUTTONBOX_START
 387  * or %GTK_BUTTONBOX_END, then the secondary children are aligned at
 388  * the other end of the button box from the main children. For the
 389  * other styles, they appear immediately next to the main children.
 390  **/
 391 void
 392 gtk_button_box_set_child_secondary (GtkButtonBox *widget,
 393                                     GtkWidget    *child,
 394                                     gboolean      is_secondary)
 395 {
 396   g_return_if_fail (GTK_IS_BUTTON_BOX (widget));
 397   g_return_if_fail (GTK_IS_WIDGET (child));
 398   g_return_if_fail (gtk_widget_get_parent (child) == GTK_WIDGET (widget));
 399
 400   g_object_set_data (G_OBJECT (child),
 401                      GTK_BOX_SECONDARY_CHILD,
 402                      is_secondary ? GINT_TO_POINTER (1) : NULL);
 403   gtk_widget_child_notify (child, "secondary");
 404
 405   if (gtk_widget_get_visible (GTK_WIDGET (widget)) &&
 406       gtk_widget_get_visible (child))
 407     gtk_widget_queue_resize (child);
 408 }
 409
 410 /* Ask children how much space they require and round up
 411  * to match minimum size and internal padding.
 412  * Returns the size each single child should have.
 413  */
 414 static void
 415 gtk_button_box_child_requisition (GtkWidget  *widget,
 416                                   gint       *nvis_children,
 417                                   gint       *nvis_secondaries,
 418                                   gint      **widths,
 419                                   gint      **heights)
 420 {
 421   GtkButtonBox *bbox;
 422   GList *children, *list;
 423   gint nchildren;
 424   gint nsecondaries;
 425   gint needed_width;
 426   gint needed_height;
 427   gint avg_w, avg_h;
 428   GtkRequisition child_requisition;
 429   gint ipad_w;
 430   gint ipad_h;
 431   gint child_min_width;
 432   gint child_min_height;
 433   gint ipad_x;
 434   gint ipad_y;
 435   gboolean homogeneous;
 436   gint i;
 437
 438   g_return_if_fail (GTK_IS_BUTTON_BOX (widget));
 439
 440   bbox = GTK_BUTTON_BOX (widget);
 441
 442   homogeneous = gtk_box_get_homogeneous (GTK_BOX (widget));
 443
 444   gtk_widget_style_get (widget,
 445                         "child-min-width", &child_min_width,
 446                         "child-min-height", &child_min_height,
 447                         "child-internal-pad-x", &ipad_x,
 448                         "child-internal-pad-y", &ipad_y,
 449                         NULL);
 450
 451   nchildren = 0;
 452   nsecondaries = 0;
 453   list = children = _gtk_box_get_children (GTK_BOX (bbox));
 454   needed_width = child_min_width;
 455   needed_height = child_min_height;
 456   ipad_w = ipad_x * 2;
 457   ipad_h = ipad_y * 2;
 458
 459   avg_w = avg_h = 0;
 460   while (children)
 461     {
 462       GtkWidget *child;
 463
 464       child = children->data;
 465       children = children->next;
 466
 467       if (gtk_widget_get_visible (child))
 468         {
 469           nchildren += 1;
 470           gtk_widget_get_preferred_size (child,
 471                                          &child_requisition, NULL);
 472           avg_w += child_requisition.width + ipad_w;
 473           avg_h += child_requisition.height + ipad_h;
 474         }
 475     }
 476   avg_w /= MAX (nchildren, 1);
 477   avg_h /= MAX (nchildren, 1);
 478
 479   *widths = g_new (gint, nchildren);
 480   *heights = g_new (gint, nchildren);
 481
 482   i = 0;
 483   children = list;
 484   while (children)
 485     {
 486       GtkWidget *child;
 487       gboolean is_secondary;
 488
 489       child = children->data;
 490       children = children->next;
 491
 492       if (gtk_widget_get_visible (child))
 493         {
 494           is_secondary = gtk_button_box_get_child_secondary (bbox, child);
 495           if (is_secondary)
 496             nsecondaries++;
 497
 498           gtk_widget_get_preferred_size (child, &child_requisition, NULL);
 499
 500           if (homogeneous || (child_requisition.width + ipad_w < avg_w * 1.5))
 501             {
 502               (*widths)[i] = -1;
 503               if (child_requisition.width + ipad_w > needed_width)
 504                 needed_width = child_requisition.width + ipad_w;
 505             }
 506           else
 507             {
 508               (*widths)[i] = child_requisition.width + ipad_w;
 509             }
 510
 511           if (homogeneous || (child_requisition.height + ipad_h < avg_h * 1.5))
 512             {
 513               (*heights)[i] = -1;
 514               if (child_requisition.height + ipad_h > needed_height)
 515                 needed_height = child_requisition.height + ipad_h;
 516             }
 517           else
 518             {
 519               (*heights)[i] = child_requisition.height + ipad_h;
 520             }
 521
 522           i++;
 523         }
 524     }
 525
 526   g_list_free (list);
 527
 528   for (i = 0; i < nchildren; i++)
 529     {
 530       if ((*widths)[i] == -1)
 531         (*widths)[i] = needed_width;
 532       if ((*heights)[i] == -1)
 533         (*heights)[i] = needed_height;
 534     }
 535
 536   if (nvis_children)
 537     *nvis_children = nchildren;
 538
 539   if (nvis_secondaries)
 540     *nvis_secondaries = nsecondaries;
 541 }
 542
 543 static void
 544 gtk_button_box_size_request (GtkWidget      *widget,
 545                              GtkRequisition *requisition)
 546 {
 547   GtkButtonBoxPrivate *priv;
 548   GtkButtonBox *bbox;
 549   gint nvis_children;
 550   gint max_size;
 551   gint total_size;
 552   gint spacing;
 553   GtkOrientation orientation;
 554   gint *widths;
 555   gint *heights;
 556   gint i;
 557
 558   bbox = GTK_BUTTON_BOX (widget);
 559   priv = bbox->priv;
 560
 561   orientation = gtk_orientable_get_orientation (GTK_ORIENTABLE (widget));
 562   spacing = gtk_box_get_spacing (GTK_BOX (widget));
 563
 564   gtk_button_box_child_requisition (widget,
 565                                     &nvis_children,
 566                                     NULL,
 567                                     &widths, &heights);
 568
 569   max_size = 0;
 570   total_size = 0;
 571   for (i = 0; i < nvis_children; i++)
 572     {
 573       if (orientation == GTK_ORIENTATION_HORIZONTAL)
 574         {
 575           total_size += widths[i];
 576           max_size = MAX (max_size, heights[i]);
 577         }
 578       else
 579         {
 580           total_size += heights[i];
 581           max_size = MAX (max_size, widths[i]);
 582         }
 583     }
 584   g_free (widths);
 585   g_free (heights);
 586
 587   if (nvis_children == 0)
 588     {
 589       requisition->width = 0;
 590       requisition->height = 0;
 591     }
 592   else
 593     {
 594       switch (priv->layout_style)
 595         {
 596           case GTK_BUTTONBOX_SPREAD:
 597             if (orientation == GTK_ORIENTATION_HORIZONTAL)
 598               requisition->width = total_size + ((nvis_children + 1)*spacing);
 599             else
 600               requisition->height = total_size + ((nvis_children + 1)*spacing);
 601
 602             break;
 603           case GTK_BUTTONBOX_EDGE:
 604           case GTK_BUTTONBOX_START:
 605           case GTK_BUTTONBOX_END:
 606           case GTK_BUTTONBOX_CENTER:
 607             if (orientation == GTK_ORIENTATION_HORIZONTAL)
 608               requisition->width = total_size + ((nvis_children - 1)*spacing);
 609             else
 610               requisition->height = total_size + ((nvis_children - 1)*spacing);
 611
 612             break;
 613           default:
 614             g_assert_not_reached ();
 615             break;
 616         }
 617
 618       if (orientation == GTK_ORIENTATION_HORIZONTAL)
 619         requisition->height = max_size;
 620       else
 621         requisition->width = max_size;
 622     }
 623 }
 624
 625 static void
 626 gtk_button_box_get_preferred_width (GtkWidget *widget,
 627                                     gint      *minimum,
 628                                     gint      *natural)
 629 {
 630   GtkRequisition requisition;
 631
 632   gtk_button_box_size_request (widget, &requisition);
 633
 634   *minimum = *natural = requisition.width;
 635 }
 636
 637 static void
 638 gtk_button_box_get_preferred_height (GtkWidget *widget,
 639                                      gint      *minimum,
 640                                      gint      *natural)
 641 {
 642   GtkRequisition requisition;
 643
 644   gtk_button_box_size_request (widget, &requisition);
 645
 646   *minimum = *natural = requisition.height;
 647 }
 648
 649 static void
 650 gtk_button_box_get_preferred_width_for_height (GtkWidget *widget,
 651                                                gint       height,
 652                                                gint      *minimum,
 653                                                gint      *natural)
 654 {
 655   gtk_button_box_get_preferred_width (widget, minimum, natural);
 656 }
 657
 658 static void
 659 gtk_button_box_get_preferred_height_for_width (GtkWidget *widget,
 660                                                gint       width,
 661                                                gint      *minimum,
 662                                                gint      *natural)
 663 {
 664   gtk_button_box_get_preferred_height (widget, minimum, natural);
 665 }
 666
 667 static void
 668 gtk_button_box_size_allocate (GtkWidget     *widget,
 669                               GtkAllocation *allocation)
 670 {
 671   GtkButtonBoxPrivate *priv;
 672   GtkButtonBox *bbox;
 673   GList *children, *list;
 674   GtkAllocation child_allocation;
 675   gint nvis_children;
 676   gint n_primaries;
 677   gint n_secondaries;
 678   gint x = 0;
 679   gint y = 0;
 680   gint secondary_x = 0;
 681   gint secondary_y = 0;
 682   gint width = 0;
 683   gint height = 0;
 684   gint childspacing = 0;
 685   gint spacing;
 686   GtkOrientation orientation;
 687   gint ipad_x, ipad_y;
 688   gint *widths;
 689   gint *heights;
 690   gint *sizes;
 691   gint primary_size;
 692   gint secondary_size;
 693   gint total_size;
 694   gint i;
 695
 696   bbox = GTK_BUTTON_BOX (widget);
 697   priv = bbox->priv;
 698
 699   orientation = gtk_orientable_get_orientation (GTK_ORIENTABLE (widget));
 700   spacing = gtk_box_get_spacing (GTK_BOX (widget));
 701
 702   gtk_widget_style_get (widget,
 703                         "child-internal-pad-x", &ipad_x,
 704                         "child-internal-pad-y", &ipad_y,
 705                         NULL);
 706   gtk_button_box_child_requisition (widget,
 707                                     &nvis_children,
 708                                     &n_secondaries,
 709                                     &widths, &heights);
 710
 711   n_primaries = nvis_children - n_secondaries;
 712   primary_size = 0;
 713   secondary_size = 0;
 714   if (orientation == GTK_ORIENTATION_HORIZONTAL)
 715     sizes = widths;
 716   else
 717     sizes = heights;
 718
 719   i = 0;
 720   list = children = _gtk_box_get_children (GTK_BOX (widget));
 721   while (children)
 722     {
 723       GtkWidget *child;
 724
 725       child = children->data;
 726       children = children->next;
 727
 728       if (gtk_widget_get_visible (child))
 729         {
 730           if (gtk_button_box_get_child_secondary (bbox, child))
 731             secondary_size += sizes[i];
 732           else
 733             primary_size += sizes[i];
 734           i++;
 735         }
 736     }
 737   total_size = primary_size + secondary_size;
 738
 739   gtk_widget_set_allocation (widget, allocation);
 740
 741   if (orientation == GTK_ORIENTATION_HORIZONTAL)
 742     width = allocation->width;
 743   else
 744     height = allocation->height;
 745
 746   switch (priv->layout_style)
 747     {
 748       case GTK_BUTTONBOX_SPREAD:
 749
 750         if (orientation == GTK_ORIENTATION_HORIZONTAL)
 751           {
 752             childspacing = (width - total_size) / (nvis_children + 1);
 753             x = allocation->x + childspacing;
 754             secondary_x = x + primary_size + n_primaries * childspacing;
 755           }
 756         else
 757           {
 758             childspacing = (height - total_size) / (nvis_children + 1);
 759             y = allocation->y + childspacing;
 760             secondary_y = y + primary_size + n_primaries * childspacing;
 761           }
 762
 763         break;
 764
 765       case GTK_BUTTONBOX_EDGE:
 766
 767         if (orientation == GTK_ORIENTATION_HORIZONTAL)
 768           {
 769             if (nvis_children >= 2)
 770               {
 771                 childspacing = (width - total_size) / (nvis_children - 1);
 772                 x = allocation->x;
 773                 secondary_x = x + primary_size + n_primaries * childspacing;
 774               }
 775             else if (nvis_children == 1)
 776               {
 777                 /* one child, just center */
 778                 childspacing = width;
 779                 x = secondary_x = allocation->x
 780                                   + (allocation->width - widths[0]) / 2;
 781               }
 782             else
 783               {
 784                 /* zero children, meh */
 785                 childspacing = width;
 786                 x = secondary_x = allocation->x + allocation->width / 2;
 787               }
 788           }
 789         else
 790           {
 791             if (nvis_children >= 2)
 792               {
 793                 childspacing = (height - total_size) / (nvis_children - 1);
 794                 y = allocation->y;
 795                 secondary_y = y + primary_size + n_primaries * childspacing;
 796               }
 797             else if (nvis_children == 1)
 798               {
 799                 /* one child, just center */
 800                 childspacing = height;
 801                 y = secondary_y = allocation->y
 802                                      + (allocation->height - heights[0]) / 2;
 803               }
 804             else
 805               {
 806                 /* zero children, meh */
 807                 childspacing = height;
 808                 y = secondary_y = allocation->y + allocation->height / 2;
 809               }
 810           }
 811
 812         break;
 813
 814       case GTK_BUTTONBOX_START:
 815
 816         if (orientation == GTK_ORIENTATION_HORIZONTAL)
 817           {
 818             childspacing = spacing;
 819             x = allocation->x;
 820             secondary_x = allocation->x + allocation->width
 821               - secondary_size - spacing * (n_secondaries - 1);
 822           }
 823         else
 824           {
 825             childspacing = spacing;
 826             y = allocation->y;
 827             secondary_y = allocation->y + allocation->height
 828               - secondary_size - spacing * (n_secondaries - 1);
 829           }
 830
 831         break;
 832
 833       case GTK_BUTTONBOX_END:
 834
 835         if (orientation == GTK_ORIENTATION_HORIZONTAL)
 836           {
 837             childspacing = spacing;
 838             x = allocation->x + allocation->width
 839               - primary_size - spacing * (n_primaries - 1);
 840             secondary_x = allocation->x;
 841           }
 842         else
 843           {
 844             childspacing = spacing;
 845             y = allocation->y + allocation->height
 846               - primary_size - spacing * (n_primaries - 1);
 847             secondary_y = allocation->y;
 848           }
 849
 850         break;
 851
 852       case GTK_BUTTONBOX_CENTER:
 853
 854         if (orientation == GTK_ORIENTATION_HORIZONTAL)
 855           {
 856             childspacing = spacing;
 857             x = allocation->x +
 858               (allocation->width
 859                - (primary_size + spacing * (n_primaries - 1))) / 2
 860               + (secondary_size + n_secondaries * spacing) / 2;
 861             secondary_x = allocation->x;
 862           }
 863         else
 864           {
 865             childspacing = spacing;
 866             y = allocation->y +
 867               (allocation->height
 868                - (primary_size + spacing * (n_primaries - 1))) / 2
 869               + (secondary_size + n_secondaries * spacing) / 2;
 870             secondary_y = allocation->y;
 871           }
 872
 873         break;
 874
 875       default:
 876         g_assert_not_reached ();
 877         break;
 878     }
 879
 880   children = list;
 881   i = 0;
 882   while (children)
 883     {
 884       GtkWidget *child;
 885
 886       child = children->data;
 887       children = children->next;
 888
 889       if (gtk_widget_get_visible (child))
 890         {
 891           child_allocation.width = widths[i];
 892           child_allocation.height = heights[i];
 893
 894           if (orientation == GTK_ORIENTATION_HORIZONTAL)
 895             {
 896               child_allocation.y = allocation->y + (allocation->height - child_allocation.height) / 2;
 897
 898               if (gtk_button_box_get_child_secondary (bbox, child))
 899                 {
 900                   child_allocation.x = secondary_x;
 901                   secondary_x += child_allocation.width + childspacing;
 902                 }
 903               else
 904                 {
 905                   child_allocation.x = x;
 906                   x += child_allocation.width + childspacing;
 907                 }
 908
 909               if (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
 910                   child_allocation.x = (allocation->x + allocation->width)
 911                           - (child_allocation.x + child_allocation.width - allocation->x);
 912             }
 913           else
 914             {
 915               child_allocation.x = allocation->x + (allocation->width - child_allocation.width) / 2;
 916
 917               if (gtk_button_box_get_child_secondary (bbox, child))
 918                 {
 919                   child_allocation.y = secondary_y;
 920                   secondary_y += child_allocation.height + childspacing;
 921                 }
 922               else
 923                 {
 924                   child_allocation.y = y;
 925                   y += child_allocation.height + childspacing;
 926                 }
 927             }
 928
 929           gtk_widget_size_allocate (child, &child_allocation);
 930           i++;
 931         }
 932     }
 933
 934   g_list_free (list);
 935   g_free (widths);
 936   g_free (heights);
 937 }
 938
 939 /**
 940  * gtk_button_box_new:
 941  * @orientation: the box' orientation.
 942  *
 943  * Creates a new #GtkButtonBox.
 944  *
 945  * Return value: a new #GtkButtonBox.
 946  *
 947  * Since: 3.0
 948  */
 949 GtkWidget *
 950 gtk_button_box_new (GtkOrientation orientation)
 951 {
 952   return g_object_new (GTK_TYPE_BUTTON_BOX,
 953                        "orientation", orientation,
 954                        NULL);
 955 }