Pileus Git - ~andy/gtk/blob - gtk/gtkviewport.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 #include "config.h"
  28 #include "gtkviewport.h"
  29 #include "gtkintl.h"
  30 #include "gtkmarshalers.h"
  31 #include "gtkprivate.h"
  32 #include "gtkalias.h"
  33
  34 /**
  35  * SECTION:gtkviewport
  36  * @Short_description: An adapter which makes widgets scrollable
  37  * @Title: GtkViewport
  38  * @See_also:#GtkScrolledWindow, #GtkAdjustment
  39  *
  40  * The #GtkViewport widget acts as an adaptor class, implementing
  41  * scrollability for child widgets that lack their own scrolling
  42  * capabilities. Use #GtkViewport to scroll child widgets such as
  43  * #GtkTable, #GtkBox, and so on.
  44  *
  45  * If a widget has native scrolling abilities, such as #GtkTextView,
  46  * #GtkTreeView or #GtkIconview, it can be added to a #GtkScrolledWindow
  47  * with gtk_container_add(). If a widget does not, you must first add the
  48  * widget to a #GtkViewport, then add the viewport to the scrolled window.
  49  * The convenience function gtk_scrolled_window_add_with_viewport() does
  50  * exactly this, so you can ignore the presence of the viewport.
  51  */
  52
  53 enum {
  54   PROP_0,
  55   PROP_HADJUSTMENT,
  56   PROP_VADJUSTMENT,
  57   PROP_SHADOW_TYPE
  58 };
  59
  60
  61 static void gtk_viewport_finalize                 (GObject          *object);
  62 static void gtk_viewport_destroy                  (GtkObject        *object);
  63 static void gtk_viewport_set_property             (GObject         *object,
  64                                                    guint            prop_id,
  65                                                    const GValue    *value,
  66                                                    GParamSpec      *pspec);
  67 static void gtk_viewport_get_property             (GObject         *object,
  68                                                    guint            prop_id,
  69                                                    GValue          *value,
  70                                                    GParamSpec      *pspec);
  71 static void gtk_viewport_set_scroll_adjustments   (GtkViewport      *viewport,
  72                                                    GtkAdjustment    *hadjustment,
  73                                                    GtkAdjustment    *vadjustment);
  74 static void gtk_viewport_realize                  (GtkWidget        *widget);
  75 static void gtk_viewport_unrealize                (GtkWidget        *widget);
  76 static void gtk_viewport_paint                    (GtkWidget        *widget,
  77                                                    GdkRectangle     *area);
  78 static gint gtk_viewport_expose                   (GtkWidget        *widget,
  79                                                    GdkEventExpose   *event);
  80 static void gtk_viewport_add                      (GtkContainer     *container,
  81                                                    GtkWidget        *widget);
  82 static void gtk_viewport_size_request             (GtkWidget        *widget,
  83                                                    GtkRequisition   *requisition);
  84 static void gtk_viewport_size_allocate            (GtkWidget        *widget,
  85                                                    GtkAllocation    *allocation);
  86 static void gtk_viewport_adjustment_value_changed (GtkAdjustment    *adjustment,
  87                                                    gpointer          data);
  88 static void gtk_viewport_style_set                (GtkWidget *widget,
  89                                                    GtkStyle  *previous_style);
  90
  91 G_DEFINE_TYPE (GtkViewport, gtk_viewport, GTK_TYPE_BIN)
  92
  93 static void
  94 gtk_viewport_class_init (GtkViewportClass *class)
  95 {
  96   GtkObjectClass *object_class;
  97   GObjectClass   *gobject_class;
  98   GtkWidgetClass *widget_class;
  99   GtkContainerClass *container_class;
 100
 101   object_class = (GtkObjectClass*) class;
 102   gobject_class = G_OBJECT_CLASS (class);
 103   widget_class = (GtkWidgetClass*) class;
 104   container_class = (GtkContainerClass*) class;
 105
 106   gobject_class->finalize = gtk_viewport_finalize;
 107   gobject_class->set_property = gtk_viewport_set_property;
 108   gobject_class->get_property = gtk_viewport_get_property;
 109   object_class->destroy = gtk_viewport_destroy;
 110
 111   widget_class->realize = gtk_viewport_realize;
 112   widget_class->unrealize = gtk_viewport_unrealize;
 113   widget_class->expose_event = gtk_viewport_expose;
 114   widget_class->size_request = gtk_viewport_size_request;
 115   widget_class->size_allocate = gtk_viewport_size_allocate;
 116   widget_class->style_set = gtk_viewport_style_set;
 117
 118   container_class->add = gtk_viewport_add;
 119
 120   class->set_scroll_adjustments = gtk_viewport_set_scroll_adjustments;
 121
 122   g_object_class_install_property (gobject_class,
 123                                    PROP_HADJUSTMENT,
 124                                    g_param_spec_object ("hadjustment",
 125                                                         P_("Horizontal adjustment"),
 126                                                         P_("The GtkAdjustment that determines the values of the horizontal position for this viewport"),
 127                                                         GTK_TYPE_ADJUSTMENT,
 128                                                         GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT));
 129
 130   g_object_class_install_property (gobject_class,
 131                                    PROP_VADJUSTMENT,
 132                                    g_param_spec_object ("vadjustment",
 133                                                         P_("Vertical adjustment"),
 134                                                         P_("The GtkAdjustment that determines the values of the vertical position for this viewport"),
 135                                                         GTK_TYPE_ADJUSTMENT,
 136                                                         GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT));
 137
 138   g_object_class_install_property (gobject_class,
 139                                    PROP_SHADOW_TYPE,
 140                                    g_param_spec_enum ("shadow-type",
 141                                                       P_("Shadow type"),
 142                                                       P_("Determines how the shadowed box around the viewport is drawn"),
 143                                                       GTK_TYPE_SHADOW_TYPE,
 144                                                       GTK_SHADOW_IN,
 145                                                       GTK_PARAM_READWRITE));
 146
 147   /**
 148    * GtkViewport::set-scroll-adjustments
 149    * @horizontal: the horizontal #GtkAdjustment
 150    * @vertical: the vertical #GtkAdjustment
 151    *
 152    * Set the scroll adjustments for the viewport. Usually scrolled containers
 153    * like #GtkScrolledWindow will emit this signal to connect two instances
 154    * of #GtkScrollbar to the scroll directions of the #GtkViewport.
 155    */
 156   widget_class->set_scroll_adjustments_signal =
 157     g_signal_new (I_("set-scroll-adjustments"),
 158                   G_OBJECT_CLASS_TYPE (gobject_class),
 159                   G_SIGNAL_RUN_LAST | G_SIGNAL_ACTION,
 160                   G_STRUCT_OFFSET (GtkViewportClass, set_scroll_adjustments),
 161                   NULL, NULL,
 162                   _gtk_marshal_VOID__OBJECT_OBJECT,
 163                   G_TYPE_NONE, 2,
 164                   GTK_TYPE_ADJUSTMENT,
 165                   GTK_TYPE_ADJUSTMENT);
 166 }
 167
 168 static void
 169 gtk_viewport_set_property (GObject         *object,
 170                            guint            prop_id,
 171                            const GValue    *value,
 172                            GParamSpec      *pspec)
 173 {
 174   GtkViewport *viewport;
 175
 176   viewport = GTK_VIEWPORT (object);
 177
 178   switch (prop_id)
 179     {
 180     case PROP_HADJUSTMENT:
 181       gtk_viewport_set_hadjustment (viewport, g_value_get_object (value));
 182       break;
 183     case PROP_VADJUSTMENT:
 184       gtk_viewport_set_vadjustment (viewport, g_value_get_object (value));
 185       break;
 186     case PROP_SHADOW_TYPE:
 187       gtk_viewport_set_shadow_type (viewport, g_value_get_enum (value));
 188       break;
 189     default:
 190       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 191       break;
 192     }
 193 }
 194
 195 static void
 196 gtk_viewport_get_property (GObject         *object,
 197                            guint            prop_id,
 198                            GValue          *value,
 199                            GParamSpec      *pspec)
 200 {
 201   GtkViewport *viewport;
 202
 203   viewport = GTK_VIEWPORT (object);
 204
 205   switch (prop_id)
 206     {
 207     case PROP_HADJUSTMENT:
 208       g_value_set_object (value, viewport->hadjustment);
 209       break;
 210     case PROP_VADJUSTMENT:
 211       g_value_set_object (value, viewport->vadjustment);
 212       break;
 213     case PROP_SHADOW_TYPE:
 214       g_value_set_enum (value, viewport->shadow_type);
 215       break;
 216     default:
 217       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 218       break;
 219     }
 220 }
 221
 222 static void
 223 gtk_viewport_init (GtkViewport *viewport)
 224 {
 225   gtk_widget_set_has_window (GTK_WIDGET (viewport), TRUE);
 226
 227   gtk_widget_set_redraw_on_allocate (GTK_WIDGET (viewport), FALSE);
 228   gtk_container_set_resize_mode (GTK_CONTAINER (viewport), GTK_RESIZE_QUEUE);
 229
 230   viewport->shadow_type = GTK_SHADOW_IN;
 231   viewport->view_window = NULL;
 232   viewport->bin_window = NULL;
 233   viewport->hadjustment = NULL;
 234   viewport->vadjustment = NULL;
 235 }
 236
 237 /**
 238  * gtk_viewport_new:
 239  * @hadjustment: horizontal adjustment.
 240  * @vadjustment: vertical adjustment.
 241  * @returns: a new #GtkViewport.
 242  *
 243  * Creates a new #GtkViewport with the given adjustments.
 244  *
 245  **/
 246 GtkWidget*
 247 gtk_viewport_new (GtkAdjustment *hadjustment,
 248                   GtkAdjustment *vadjustment)
 249 {
 250   GtkWidget *viewport;
 251
 252   viewport = g_object_new (GTK_TYPE_VIEWPORT,
 253                              "hadjustment", hadjustment,
 254                              "vadjustment", vadjustment,
 255                              NULL);
 256
 257   return viewport;
 258 }
 259
 260 #define ADJUSTMENT_POINTER(viewport, orientation)         \
 261   (((orientation) == GTK_ORIENTATION_HORIZONTAL) ?        \
 262      &(viewport)->hadjustment : &(viewport)->vadjustment)
 263
 264 static void
 265 viewport_disconnect_adjustment (GtkViewport    *viewport,
 266                                 GtkOrientation  orientation)
 267 {
 268   GtkAdjustment **adjustmentp = ADJUSTMENT_POINTER (viewport, orientation);
 269
 270   if (*adjustmentp)
 271     {
 272       g_signal_handlers_disconnect_by_func (*adjustmentp,
 273                                             gtk_viewport_adjustment_value_changed,
 274                                             viewport);
 275       g_object_unref (*adjustmentp);
 276       *adjustmentp = NULL;
 277     }
 278 }
 279
 280 static void
 281 gtk_viewport_finalize (GObject *object)
 282 {
 283   GtkViewport *viewport = GTK_VIEWPORT (object);
 284
 285   viewport_disconnect_adjustment (viewport, GTK_ORIENTATION_HORIZONTAL);
 286   viewport_disconnect_adjustment (viewport, GTK_ORIENTATION_VERTICAL);
 287
 288   G_OBJECT_CLASS (gtk_viewport_parent_class)->finalize (object);
 289 }
 290
 291 static void
 292 gtk_viewport_destroy (GtkObject *object)
 293 {
 294   GtkViewport *viewport = GTK_VIEWPORT (object);
 295
 296   viewport_disconnect_adjustment (viewport, GTK_ORIENTATION_HORIZONTAL);
 297   viewport_disconnect_adjustment (viewport, GTK_ORIENTATION_VERTICAL);
 298
 299   GTK_OBJECT_CLASS (gtk_viewport_parent_class)->destroy (object);
 300 }
 301
 302 /**
 303  * gtk_viewport_get_hadjustment:
 304  * @viewport: a #GtkViewport.
 305  *
 306  * Returns the horizontal adjustment of the viewport.
 307  *
 308  * Return value: the horizontal adjustment of @viewport.
 309  **/
 310 GtkAdjustment*
 311 gtk_viewport_get_hadjustment (GtkViewport *viewport)
 312 {
 313   g_return_val_if_fail (GTK_IS_VIEWPORT (viewport), NULL);
 314
 315   if (!viewport->hadjustment)
 316     gtk_viewport_set_hadjustment (viewport, NULL);
 317
 318   return viewport->hadjustment;
 319 }
 320
 321 /**
 322  * gtk_viewport_get_vadjustment:
 323  * @viewport: a #GtkViewport.
 324  *
 325  * Returns the vertical adjustment of the viewport.
 326  *
 327  * Return value: the vertical adjustment of @viewport.
 328  **/
 329 GtkAdjustment*
 330 gtk_viewport_get_vadjustment (GtkViewport *viewport)
 331 {
 332   g_return_val_if_fail (GTK_IS_VIEWPORT (viewport), NULL);
 333
 334   if (!viewport->vadjustment)
 335     gtk_viewport_set_vadjustment (viewport, NULL);
 336
 337   return viewport->vadjustment;
 338 }
 339
 340 static void
 341 viewport_get_view_allocation (GtkViewport   *viewport,
 342                               GtkAllocation *view_allocation)
 343 {
 344   GtkWidget *widget = GTK_WIDGET (viewport);
 345   GtkAllocation *allocation = &widget->allocation;
 346   gint border_width = GTK_CONTAINER (viewport)->border_width;
 347
 348   view_allocation->x = 0;
 349   view_allocation->y = 0;
 350
 351   if (viewport->shadow_type != GTK_SHADOW_NONE)
 352     {
 353       view_allocation->x = widget->style->xthickness;
 354       view_allocation->y = widget->style->ythickness;
 355     }
 356
 357   view_allocation->width = MAX (1, allocation->width - view_allocation->x * 2 - border_width * 2);
 358   view_allocation->height = MAX (1, allocation->height - view_allocation->y * 2 - border_width * 2);
 359 }
 360
 361 static void
 362 viewport_reclamp_adjustment (GtkAdjustment *adjustment,
 363                              gboolean      *value_changed)
 364 {
 365   gdouble value = adjustment->value;
 366
 367   value = CLAMP (value, 0, adjustment->upper - adjustment->page_size);
 368   if (value != adjustment->value)
 369     {
 370       adjustment->value = value;
 371       if (value_changed)
 372         *value_changed = TRUE;
 373     }
 374   else if (value_changed)
 375     *value_changed = FALSE;
 376 }
 377
 378 static void
 379 viewport_set_hadjustment_values (GtkViewport *viewport,
 380                                  gboolean    *value_changed)
 381 {
 382   GtkBin *bin = GTK_BIN (viewport);
 383   GtkAllocation view_allocation;
 384   GtkAdjustment *hadjustment = gtk_viewport_get_hadjustment (viewport);
 385   gdouble old_page_size;
 386   gdouble old_upper;
 387   gdouble old_value;
 388
 389   viewport_get_view_allocation (viewport, &view_allocation);
 390
 391   old_page_size = hadjustment->page_size;
 392   old_upper = hadjustment->upper;
 393   old_value = hadjustment->value;
 394   hadjustment->page_size = view_allocation.width;
 395   hadjustment->step_increment = view_allocation.width * 0.1;
 396   hadjustment->page_increment = view_allocation.width * 0.9;
 397
 398   hadjustment->lower = 0;
 399
 400   if (bin->child && gtk_widget_get_visible (bin->child))
 401     {
 402       GtkRequisition child_requisition;
 403
 404       gtk_widget_get_child_requisition (bin->child, &child_requisition);
 405       hadjustment->upper = MAX (child_requisition.width, view_allocation.width);
 406     }
 407   else
 408     hadjustment->upper = view_allocation.width;
 409
 410   if (gtk_widget_get_direction (GTK_WIDGET (viewport)) == GTK_TEXT_DIR_RTL)
 411     {
 412       gdouble dist = old_upper - (old_value + old_page_size);
 413       hadjustment->value = hadjustment->upper - dist - hadjustment->page_size;
 414       viewport_reclamp_adjustment (hadjustment, value_changed);
 415       *value_changed = (old_value != hadjustment->value);
 416     }
 417   else
 418     viewport_reclamp_adjustment (hadjustment, value_changed);
 419 }
 420
 421 static void
 422 viewport_set_vadjustment_values (GtkViewport *viewport,
 423                                  gboolean    *value_changed)
 424 {
 425   GtkBin *bin = GTK_BIN (viewport);
 426   GtkAllocation view_allocation;
 427   GtkAdjustment *vadjustment = gtk_viewport_get_vadjustment (viewport);
 428
 429   viewport_get_view_allocation (viewport, &view_allocation);
 430
 431   vadjustment->page_size = view_allocation.height;
 432   vadjustment->step_increment = view_allocation.height * 0.1;
 433   vadjustment->page_increment = view_allocation.height * 0.9;
 434
 435   vadjustment->lower = 0;
 436
 437   if (bin->child && gtk_widget_get_visible (bin->child))
 438     {
 439       GtkRequisition child_requisition;
 440
 441       gtk_widget_get_child_requisition (bin->child, &child_requisition);
 442       vadjustment->upper = MAX (child_requisition.height, view_allocation.height);
 443     }
 444   else
 445     vadjustment->upper = view_allocation.height;
 446
 447   viewport_reclamp_adjustment (vadjustment, value_changed);
 448 }
 449
 450 static void
 451 viewport_set_adjustment (GtkViewport    *viewport,
 452                          GtkOrientation  orientation,
 453                          GtkAdjustment  *adjustment)
 454 {
 455   GtkAdjustment **adjustmentp = ADJUSTMENT_POINTER (viewport, orientation);
 456   gboolean value_changed;
 457
 458   if (adjustment && adjustment == *adjustmentp)
 459     return;
 460
 461   if (!adjustment)
 462     adjustment = GTK_ADJUSTMENT (gtk_adjustment_new (0.0, 0.0, 0.0,
 463                                                      0.0, 0.0, 0.0));
 464   viewport_disconnect_adjustment (viewport, orientation);
 465   *adjustmentp = adjustment;
 466   g_object_ref_sink (adjustment);
 467
 468   if (orientation == GTK_ORIENTATION_HORIZONTAL)
 469     viewport_set_hadjustment_values (viewport, &value_changed);
 470   else
 471     viewport_set_vadjustment_values (viewport, &value_changed);
 472
 473   g_signal_connect (adjustment, "value-changed",
 474                     G_CALLBACK (gtk_viewport_adjustment_value_changed),
 475                     viewport);
 476
 477   gtk_adjustment_changed (adjustment);
 478
 479   if (value_changed)
 480     gtk_adjustment_value_changed (adjustment);
 481   else
 482     gtk_viewport_adjustment_value_changed (adjustment, viewport);
 483 }
 484
 485 /**
 486  * gtk_viewport_set_hadjustment:
 487  * @viewport: a #GtkViewport.
 488  * @adjustment: (allow-none): a #GtkAdjustment.
 489  *
 490  * Sets the horizontal adjustment of the viewport.
 491  **/
 492 void
 493 gtk_viewport_set_hadjustment (GtkViewport   *viewport,
 494                               GtkAdjustment *adjustment)
 495 {
 496   g_return_if_fail (GTK_IS_VIEWPORT (viewport));
 497   if (adjustment)
 498     g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 499
 500   viewport_set_adjustment (viewport, GTK_ORIENTATION_HORIZONTAL, adjustment);
 501
 502   g_object_notify (G_OBJECT (viewport), "hadjustment");
 503 }
 504
 505 /**
 506  * gtk_viewport_set_vadjustment:
 507  * @viewport: a #GtkViewport.
 508  * @adjustment: (allow-none): a #GtkAdjustment.
 509  *
 510  * Sets the vertical adjustment of the viewport.
 511  **/
 512 void
 513 gtk_viewport_set_vadjustment (GtkViewport   *viewport,
 514                               GtkAdjustment *adjustment)
 515 {
 516   g_return_if_fail (GTK_IS_VIEWPORT (viewport));
 517   if (adjustment)
 518     g_return_if_fail (GTK_IS_ADJUSTMENT (adjustment));
 519
 520   viewport_set_adjustment (viewport, GTK_ORIENTATION_VERTICAL, adjustment);
 521
 522   g_object_notify (G_OBJECT (viewport), "vadjustment");
 523 }
 524
 525 static void
 526 gtk_viewport_set_scroll_adjustments (GtkViewport      *viewport,
 527                                      GtkAdjustment    *hadjustment,
 528                                      GtkAdjustment    *vadjustment)
 529 {
 530   gtk_viewport_set_hadjustment (viewport, hadjustment);
 531   gtk_viewport_set_vadjustment (viewport, vadjustment);
 532 }
 533
 534 /**
 535  * gtk_viewport_set_shadow_type:
 536  * @viewport: a #GtkViewport.
 537  * @type: the new shadow type.
 538  *
 539  * Sets the shadow type of the viewport.
 540  **/
 541 void
 542 gtk_viewport_set_shadow_type (GtkViewport   *viewport,
 543                               GtkShadowType  type)
 544 {
 545   g_return_if_fail (GTK_IS_VIEWPORT (viewport));
 546
 547   if ((GtkShadowType) viewport->shadow_type != type)
 548     {
 549       viewport->shadow_type = type;
 550
 551       if (gtk_widget_get_visible (GTK_WIDGET (viewport)))
 552         {
 553           gtk_widget_size_allocate (GTK_WIDGET (viewport), &(GTK_WIDGET (viewport)->allocation));
 554           gtk_widget_queue_draw (GTK_WIDGET (viewport));
 555         }
 556
 557       g_object_notify (G_OBJECT (viewport), "shadow-type");
 558     }
 559 }
 560
 561 /**
 562  * gtk_viewport_get_shadow_type:
 563  * @viewport: a #GtkViewport
 564  *
 565  * Gets the shadow type of the #GtkViewport. See
 566  * gtk_viewport_set_shadow_type().
 567
 568  * Return value: the shadow type
 569  **/
 570 GtkShadowType
 571 gtk_viewport_get_shadow_type (GtkViewport *viewport)
 572 {
 573   g_return_val_if_fail (GTK_IS_VIEWPORT (viewport), GTK_SHADOW_NONE);
 574
 575   return viewport->shadow_type;
 576 }
 577
 578 /**
 579  * gtk_viewport_get_bin_window:
 580  * @viewport: a #GtkViewport
 581  *
 582  * Gets the bin window of the #GtkViewport.
 583  *
 584  * Return value: a #GdkWindow
 585  *
 586  * Since: 2.20
 587  **/
 588 GdkWindow*
 589 gtk_viewport_get_bin_window (GtkViewport *viewport)
 590 {
 591   g_return_val_if_fail (GTK_IS_VIEWPORT (viewport), NULL);
 592
 593   return viewport->bin_window;
 594 }
 595
 596 static void
 597 gtk_viewport_realize (GtkWidget *widget)
 598 {
 599   GtkViewport *viewport = GTK_VIEWPORT (widget);
 600   GtkBin *bin = GTK_BIN (widget);
 601   GtkAdjustment *hadjustment = gtk_viewport_get_hadjustment (viewport);
 602   GtkAdjustment *vadjustment = gtk_viewport_get_vadjustment (viewport);
 603   gint border_width = GTK_CONTAINER (widget)->border_width;
 604
 605   GtkAllocation view_allocation;
 606   GdkWindowAttr attributes;
 607   gint attributes_mask;
 608   gint event_mask;
 609
 610   gtk_widget_set_realized (widget, TRUE);
 611
 612   attributes.x = widget->allocation.x + border_width;
 613   attributes.y = widget->allocation.y + border_width;
 614   attributes.width = widget->allocation.width - border_width * 2;
 615   attributes.height = widget->allocation.height - border_width * 2;
 616   attributes.window_type = GDK_WINDOW_CHILD;
 617   attributes.wclass = GDK_INPUT_OUTPUT;
 618   attributes.visual = gtk_widget_get_visual (widget);
 619   attributes.colormap = gtk_widget_get_colormap (widget);
 620
 621   event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
 622   /* We select on button_press_mask so that button 4-5 scrolls are trapped.
 623    */
 624   attributes.event_mask = event_mask | GDK_BUTTON_PRESS_MASK;
 625
 626   attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
 627
 628   widget->window = gdk_window_new (gtk_widget_get_parent_window (widget),
 629                                    &attributes, attributes_mask);
 630   gdk_window_set_user_data (widget->window, viewport);
 631
 632   viewport_get_view_allocation (viewport, &view_allocation);
 633
 634   attributes.x = view_allocation.x;
 635   attributes.y = view_allocation.y;
 636   attributes.width = view_allocation.width;
 637   attributes.height = view_allocation.height;
 638   attributes.event_mask = 0;
 639
 640   viewport->view_window = gdk_window_new (widget->window, &attributes, attributes_mask);
 641   gdk_window_set_user_data (viewport->view_window, viewport);
 642
 643   gdk_window_set_back_pixmap (viewport->view_window, NULL, FALSE);
 644
 645   attributes.x = - hadjustment->value;
 646   attributes.y = - vadjustment->value;
 647   attributes.width = hadjustment->upper;
 648   attributes.height = vadjustment->upper;
 649
 650   attributes.event_mask = event_mask;
 651
 652   viewport->bin_window = gdk_window_new (viewport->view_window, &attributes, attributes_mask);
 653   gdk_window_set_user_data (viewport->bin_window, viewport);
 654
 655   if (bin->child)
 656     gtk_widget_set_parent_window (bin->child, viewport->bin_window);
 657
 658   widget->style = gtk_style_attach (widget->style, widget->window);
 659   gtk_style_set_background (widget->style, widget->window, GTK_STATE_NORMAL);
 660   gtk_style_set_background (widget->style, viewport->bin_window, GTK_STATE_NORMAL);
 661
 662   /* Call paint here to allow a theme to set the background without flashing
 663    */
 664   gtk_paint_flat_box(widget->style, viewport->bin_window, GTK_STATE_NORMAL,
 665                      GTK_SHADOW_NONE,
 666                      NULL, widget, "viewportbin",
 667                      0, 0, -1, -1);
 668
 669   gdk_window_show (viewport->bin_window);
 670   gdk_window_show (viewport->view_window);
 671 }
 672
 673 static void
 674 gtk_viewport_unrealize (GtkWidget *widget)
 675 {
 676   GtkViewport *viewport = GTK_VIEWPORT (widget);
 677
 678   gdk_window_set_user_data (viewport->view_window, NULL);
 679   gdk_window_destroy (viewport->view_window);
 680   viewport->view_window = NULL;
 681
 682   gdk_window_set_user_data (viewport->bin_window, NULL);
 683   gdk_window_destroy (viewport->bin_window);
 684   viewport->bin_window = NULL;
 685
 686   GTK_WIDGET_CLASS (gtk_viewport_parent_class)->unrealize (widget);
 687 }
 688
 689 static void
 690 gtk_viewport_paint (GtkWidget    *widget,
 691                     GdkRectangle *area)
 692 {
 693   if (gtk_widget_is_drawable (widget))
 694     {
 695       GtkViewport *viewport = GTK_VIEWPORT (widget);
 696
 697       gtk_paint_shadow (widget->style, widget->window,
 698                         GTK_STATE_NORMAL, viewport->shadow_type,
 699                         area, widget, "viewport",
 700                         0, 0, -1, -1);
 701     }
 702 }
 703
 704 static gint
 705 gtk_viewport_expose (GtkWidget      *widget,
 706                      GdkEventExpose *event)
 707 {
 708   GtkViewport *viewport;
 709
 710   if (gtk_widget_is_drawable (widget))
 711     {
 712       viewport = GTK_VIEWPORT (widget);
 713
 714       if (event->window == widget->window)
 715         gtk_viewport_paint (widget, &event->area);
 716       else if (event->window == viewport->bin_window)
 717         {
 718           gtk_paint_flat_box(widget->style, viewport->bin_window,
 719                              GTK_STATE_NORMAL, GTK_SHADOW_NONE,
 720                              &event->area, widget, "viewportbin",
 721                              0, 0, -1, -1);
 722
 723           GTK_WIDGET_CLASS (gtk_viewport_parent_class)->expose_event (widget, event);
 724         }
 725     }
 726
 727   return FALSE;
 728 }
 729
 730 static void
 731 gtk_viewport_add (GtkContainer *container,
 732                   GtkWidget    *child)
 733 {
 734   GtkBin *bin = GTK_BIN (container);
 735
 736   g_return_if_fail (bin->child == NULL);
 737
 738   gtk_widget_set_parent_window (child, GTK_VIEWPORT (bin)->bin_window);
 739
 740   GTK_CONTAINER_CLASS (gtk_viewport_parent_class)->add (container, child);
 741 }
 742
 743 static void
 744 gtk_viewport_size_request (GtkWidget      *widget,
 745                            GtkRequisition *requisition)
 746 {
 747   GtkBin *bin = GTK_BIN (widget);
 748   GtkRequisition child_requisition;
 749
 750   requisition->width = GTK_CONTAINER (widget)->border_width;
 751
 752   requisition->height = GTK_CONTAINER (widget)->border_width;
 753
 754   if (GTK_VIEWPORT (widget)->shadow_type != GTK_SHADOW_NONE)
 755     {
 756       requisition->width += 2 * widget->style->xthickness;
 757       requisition->height += 2 * widget->style->ythickness;
 758     }
 759
 760   if (bin->child && gtk_widget_get_visible (bin->child))
 761     {
 762       gtk_widget_size_request (bin->child, &child_requisition);
 763       requisition->width += child_requisition.width;
 764       requisition->height += child_requisition.height;
 765     }
 766 }
 767
 768 static void
 769 gtk_viewport_size_allocate (GtkWidget     *widget,
 770                             GtkAllocation *allocation)
 771 {
 772   GtkViewport *viewport = GTK_VIEWPORT (widget);
 773   GtkBin *bin = GTK_BIN (widget);
 774   gint border_width = GTK_CONTAINER (widget)->border_width;
 775   gboolean hadjustment_value_changed, vadjustment_value_changed;
 776   GtkAdjustment *hadjustment = gtk_viewport_get_hadjustment (viewport);
 777   GtkAdjustment *vadjustment = gtk_viewport_get_vadjustment (viewport);
 778   GtkAllocation child_allocation;
 779
 780   /* If our size changed, and we have a shadow, queue a redraw on widget->window to
 781    * redraw the shadow correctly.
 782    */
 783   if (gtk_widget_get_mapped (widget) &&
 784       viewport->shadow_type != GTK_SHADOW_NONE &&
 785       (widget->allocation.width != allocation->width ||
 786        widget->allocation.height != allocation->height))
 787     gdk_window_invalidate_rect (widget->window, NULL, FALSE);
 788
 789   widget->allocation = *allocation;
 790
 791   viewport_set_hadjustment_values (viewport, &hadjustment_value_changed);
 792   viewport_set_vadjustment_values (viewport, &vadjustment_value_changed);
 793
 794   child_allocation.x = 0;
 795   child_allocation.y = 0;
 796   child_allocation.width = hadjustment->upper;
 797   child_allocation.height = vadjustment->upper;
 798   if (gtk_widget_get_realized (widget))
 799     {
 800       GtkAllocation view_allocation;
 801       gdk_window_move_resize (widget->window,
 802                               allocation->x + border_width,
 803                               allocation->y + border_width,
 804                               allocation->width - border_width * 2,
 805                               allocation->height - border_width * 2);
 806
 807       viewport_get_view_allocation (viewport, &view_allocation);
 808       gdk_window_move_resize (viewport->view_window,
 809                               view_allocation.x,
 810                               view_allocation.y,
 811                               view_allocation.width,
 812                               view_allocation.height);
 813       gdk_window_move_resize (viewport->bin_window,
 814                               - hadjustment->value,
 815                               - vadjustment->value,
 816                               child_allocation.width,
 817                               child_allocation.height);
 818     }
 819   if (bin->child && gtk_widget_get_visible (bin->child))
 820     gtk_widget_size_allocate (bin->child, &child_allocation);
 821
 822   gtk_adjustment_changed (hadjustment);
 823   gtk_adjustment_changed (vadjustment);
 824   if (hadjustment_value_changed)
 825     gtk_adjustment_value_changed (hadjustment);
 826   if (vadjustment_value_changed)
 827     gtk_adjustment_value_changed (vadjustment);
 828 }
 829
 830 static void
 831 gtk_viewport_adjustment_value_changed (GtkAdjustment *adjustment,
 832                                        gpointer       data)
 833 {
 834   GtkViewport *viewport = GTK_VIEWPORT (data);
 835   GtkBin *bin = GTK_BIN (data);
 836
 837   if (bin->child && gtk_widget_get_visible (bin->child) &&
 838       gtk_widget_get_realized (GTK_WIDGET (viewport)))
 839     {
 840       GtkAdjustment *hadjustment = gtk_viewport_get_hadjustment (viewport);
 841       GtkAdjustment *vadjustment = gtk_viewport_get_vadjustment (viewport);
 842       gint old_x, old_y;
 843       gint new_x, new_y;
 844
 845       gdk_window_get_position (viewport->bin_window, &old_x, &old_y);
 846       new_x = - hadjustment->value;
 847       new_y = - vadjustment->value;
 848
 849       if (new_x != old_x || new_y != old_y)
 850         {
 851           gdk_window_move (viewport->bin_window, new_x, new_y);
 852           gdk_window_process_updates (viewport->bin_window, TRUE);
 853         }
 854     }
 855 }
 856
 857 static void
 858 gtk_viewport_style_set (GtkWidget *widget,
 859                         GtkStyle  *previous_style)
 860 {
 861    if (gtk_widget_get_realized (widget) &&
 862        gtk_widget_get_has_window (widget))
 863      {
 864         GtkViewport *viewport = GTK_VIEWPORT (widget);
 865
 866         gtk_style_set_background (widget->style, viewport->bin_window, GTK_STATE_NORMAL);
 867         gtk_style_set_background (widget->style, widget->window, widget->state);
 868      }
 869 }
 870
 871 #define __GTK_VIEWPORT_C__
 872 #include "gtkaliasdef.c"