2 * This library is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU Lesser General Public
4 * License as published by the Free Software Foundation; either
5 * version 2 of the License, or (at your option) any later version.
7 * This library is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * Lesser General Public License for more details.
12 * You should have received a copy of the GNU Lesser General Public
13 * License along with this library; if not, write to the
14 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
15 * Boston, MA 02111-1307, USA.
17 * Authors: Cody Russell <crussell@canonical.com>
18 * Alexander Larsson <alexl@redhat.com>
21 #include "gtkoffscreenwindow.h"
25 * SECTION:gtkoffscreenwindow
26 * @short_description: A toplevel container widget used to manage offscreen
27 * rendering of child widgets.
28 * @title: GtkOffscreenWindow
30 * #GtkOffscreenWindow is strictly intended to be used for obtaining
31 * snapshots of widgets that are not part of a normal widget hierarchy.
32 * It differs from gtk_widget_get_snapshot() in that the widget you
33 * want to get a snapshot of need not be displayed on the user's screen
34 * as a part of a widget hierarchy. However, since #GtkOffscreenWindow
35 * is a toplevel widget you cannot obtain snapshots of a full window
36 * with it since you cannot pack a toplevel widget in another toplevel.
38 * The idea is to take a widget and manually set the state of it,
39 * add it to a #GtkOffscreenWindow and then retrieve the snapshot
40 * as a #GdkPixmap or #GdkPixbuf.
42 * #GtkOffscreenWindow derives from #GtkWindow only as an implementation
43 * detail. Applications should not use any API specific to #GtkWindow
44 * to operate on this object. It should be treated as a #GtkBin that
45 * has no parent widget.
47 * When contained offscreen widgets are redrawn, #GtkOffscreenWindow
48 * will emit a #GtkWidget::damage-event signal.
51 G_DEFINE_TYPE (GtkOffscreenWindow, gtk_offscreen_window, GTK_TYPE_WINDOW);
54 gtk_offscreen_window_size_request (GtkWidget *widget,
55 GtkRequisition *requisition)
57 GtkBin *bin = GTK_BIN (widget);
59 gint default_width, default_height;
61 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
63 requisition->width = border_width * 2;
64 requisition->height = border_width * 2;
66 if (bin->child && gtk_widget_get_visible (bin->child))
68 GtkRequisition child_req;
70 gtk_widget_size_request (bin->child, &child_req);
72 requisition->width += child_req.width;
73 requisition->height += child_req.height;
76 gtk_window_get_default_size (GTK_WINDOW (widget),
77 &default_width, &default_height);
78 if (default_width > 0)
79 requisition->width = default_width;
81 if (default_height > 0)
82 requisition->height = default_height;
86 gtk_offscreen_window_size_allocate (GtkWidget *widget,
87 GtkAllocation *allocation)
89 GtkBin *bin = GTK_BIN (widget);
92 widget->allocation = *allocation;
94 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
96 if (GTK_WIDGET_REALIZED (widget))
97 gdk_window_move_resize (widget->window,
103 if (bin->child && gtk_widget_get_visible (bin->child))
105 GtkAllocation child_alloc;
107 child_alloc.x = border_width;
108 child_alloc.y = border_width;
109 child_alloc.width = allocation->width - 2 * border_width;
110 child_alloc.height = allocation->height - 2 * border_width;
112 gtk_widget_size_allocate (bin->child, &child_alloc);
115 gtk_widget_queue_draw (widget);
119 gtk_offscreen_window_realize (GtkWidget *widget)
122 GdkWindowAttr attributes;
123 gint attributes_mask;
126 bin = GTK_BIN (widget);
128 GTK_WIDGET_SET_FLAGS (widget, GTK_REALIZED);
130 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
132 attributes.x = widget->allocation.x;
133 attributes.y = widget->allocation.y;
134 attributes.width = widget->allocation.width;
135 attributes.height = widget->allocation.height;
136 attributes.window_type = GDK_WINDOW_OFFSCREEN;
137 attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
138 attributes.visual = gtk_widget_get_visual (widget);
139 attributes.colormap = gtk_widget_get_colormap (widget);
140 attributes.wclass = GDK_INPUT_OUTPUT;
142 attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
144 widget->window = gdk_window_new (gtk_widget_get_parent_window (widget),
145 &attributes, attributes_mask);
146 gdk_window_set_user_data (widget->window, widget);
149 gtk_widget_set_parent_window (bin->child, widget->window);
151 widget->style = gtk_style_attach (widget->style, widget->window);
153 gtk_style_set_background (widget->style, widget->window, GTK_STATE_NORMAL);
157 gtk_offscreen_window_resize (GtkWidget *widget)
159 GtkAllocation allocation = { 0, 0 };
160 GtkRequisition requisition;
162 gtk_widget_size_request (widget, &requisition);
164 allocation.width = requisition.width;
165 allocation.height = requisition.height;
166 gtk_widget_size_allocate (widget, &allocation);
170 move_focus (GtkWidget *widget,
171 GtkDirectionType dir)
173 gtk_widget_child_focus (widget, dir);
175 if (!GTK_CONTAINER (widget)->focus_child)
176 gtk_window_set_focus (GTK_WINDOW (widget), NULL);
180 gtk_offscreen_window_show (GtkWidget *widget)
182 gboolean need_resize;
183 GtkContainer *container;
185 GTK_WIDGET_SET_FLAGS (widget, GTK_VISIBLE);
187 container = GTK_CONTAINER (widget);
188 need_resize = container->need_resize || !GTK_WIDGET_REALIZED (widget);
189 container->need_resize = FALSE;
192 gtk_offscreen_window_resize (widget);
194 gtk_widget_map (widget);
196 /* Try to make sure that we have some focused widget */
197 if (!gtk_window_get_focus (GTK_WINDOW (widget)))
198 move_focus (widget, GTK_DIR_TAB_FORWARD);
202 gtk_offscreen_window_hide (GtkWidget *widget)
204 GTK_WIDGET_UNSET_FLAGS (widget, GTK_VISIBLE);
205 gtk_widget_unmap (widget);
209 gtk_offscreen_window_check_resize (GtkContainer *container)
211 GtkWidget *widget = GTK_WIDGET (container);
213 if (gtk_widget_get_visible (widget))
214 gtk_offscreen_window_resize (widget);
218 gtk_offscreen_window_class_init (GtkOffscreenWindowClass *class)
220 GtkWidgetClass *widget_class;
221 GtkContainerClass *container_class;
223 widget_class = GTK_WIDGET_CLASS (class);
224 container_class = GTK_CONTAINER_CLASS (class);
226 widget_class->realize = gtk_offscreen_window_realize;
227 widget_class->show = gtk_offscreen_window_show;
228 widget_class->hide = gtk_offscreen_window_hide;
229 widget_class->size_request = gtk_offscreen_window_size_request;
230 widget_class->size_allocate = gtk_offscreen_window_size_allocate;
232 container_class->check_resize = gtk_offscreen_window_check_resize;
236 gtk_offscreen_window_init (GtkOffscreenWindow *window)
240 /* --- functions --- */
242 * gtk_offscreen_window_new:
244 * Creates a toplevel container widget that is used to retrieve
245 * snapshots of widgets without showing them on the screen. For
246 * widgets that are on the screen and part of a normal widget
247 * hierarchy, gtk_widget_get_snapshot() can be used instead.
249 * Return value: A pointer to a #GtkWidget
254 gtk_offscreen_window_new (void)
256 return g_object_new (gtk_offscreen_window_get_type (), NULL);
260 * gtk_offscreen_window_get_pixmap:
261 * @offscreen: the #GtkOffscreenWindow contained widget.
263 * Retrieves a snapshot of the contained widget in the form of
264 * a #GdkPixmap. If you need to keep this around over window
265 * resizes then you should add a reference to it.
267 * Returns: A #GdkPixmap pointer to the offscreen pixmap, or %NULL.
272 gtk_offscreen_window_get_pixmap (GtkOffscreenWindow *offscreen)
274 g_return_val_if_fail (GTK_IS_OFFSCREEN_WINDOW (offscreen), NULL);
276 return gdk_offscreen_window_get_pixmap (GTK_WIDGET (offscreen)->window);
280 * gtk_offscreen_window_get_pixbuf:
281 * @offscreen: the #GtkOffscreenWindow contained widget.
283 * Retrieves a snapshot of the contained widget in the form of
284 * a #GdkPixbuf. This is a new pixbuf with a reference count of 1,
285 * and the application should unreference it once it is no longer
288 * Returns: A #GdkPixbuf pointer, or %NULL.
293 gtk_offscreen_window_get_pixbuf (GtkOffscreenWindow *offscreen)
295 GdkPixmap *pixmap = NULL;
296 GdkPixbuf *pixbuf = NULL;
298 g_return_val_if_fail (GTK_IS_OFFSCREEN_WINDOW (offscreen), NULL);
300 pixmap = gdk_offscreen_window_get_pixmap (GTK_WIDGET (offscreen)->window);
306 gdk_drawable_get_size (pixmap, &width, &height);
308 pixbuf = gdk_pixbuf_get_from_drawable (NULL, pixmap, NULL,
316 #define __GTK_OFFSCREEN_WINDOW_C__
317 #include "gtkaliasdef.c"