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>
23 #include "gtkoffscreenwindow.h"
25 #include "gtksizerequest.h"
28 * SECTION:gtkoffscreenwindow
29 * @short_description: A toplevel container widget used to manage offscreen
30 * rendering of child widgets.
31 * @title: GtkOffscreenWindow
33 * #GtkOffscreenWindow is strictly intended to be used for obtaining
34 * snapshots of widgets that are not part of a normal widget hierarchy.
35 * It differs from gtk_widget_get_snapshot() in that the widget you
36 * want to get a snapshot of need not be displayed on the user's screen
37 * as a part of a widget hierarchy. However, since #GtkOffscreenWindow
38 * is a toplevel widget you cannot obtain snapshots of a full window
39 * with it since you cannot pack a toplevel widget in another toplevel.
41 * The idea is to take a widget and manually set the state of it,
42 * add it to a #GtkOffscreenWindow and then retrieve the snapshot
43 * as a #GdkPixmap or #GdkPixbuf.
45 * #GtkOffscreenWindow derives from #GtkWindow only as an implementation
46 * detail. Applications should not use any API specific to #GtkWindow
47 * to operate on this object. It should be treated as a #GtkBin that
48 * has no parent widget.
50 * When contained offscreen widgets are redrawn, #GtkOffscreenWindow
51 * will emit a #GtkWidget::damage-event signal.
54 G_DEFINE_TYPE (GtkOffscreenWindow, gtk_offscreen_window, GTK_TYPE_WINDOW);
57 gtk_offscreen_window_size_request (GtkWidget *widget,
58 GtkRequisition *requisition)
60 GtkBin *bin = GTK_BIN (widget);
63 gint default_width, default_height;
65 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
67 requisition->width = border_width * 2;
68 requisition->height = border_width * 2;
70 child = gtk_bin_get_child (bin);
72 if (child != NULL && gtk_widget_get_visible (child))
74 GtkRequisition child_req;
76 gtk_size_request_get_size (GTK_SIZE_REQUEST (child),
79 requisition->width += child_req.width;
80 requisition->height += child_req.height;
83 gtk_window_get_default_size (GTK_WINDOW (widget),
84 &default_width, &default_height);
85 if (default_width > 0)
86 requisition->width = default_width;
88 if (default_height > 0)
89 requisition->height = default_height;
93 gtk_offscreen_window_size_allocate (GtkWidget *widget,
94 GtkAllocation *allocation)
96 GtkBin *bin = GTK_BIN (widget);
100 gtk_widget_set_allocation (widget, allocation);
102 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
104 if (gtk_widget_get_realized (widget))
105 gdk_window_move_resize (gtk_widget_get_window (widget),
111 child = gtk_bin_get_child (bin);
113 if (child != NULL && gtk_widget_get_visible (child))
115 GtkAllocation child_alloc;
117 child_alloc.x = border_width;
118 child_alloc.y = border_width;
119 child_alloc.width = allocation->width - 2 * border_width;
120 child_alloc.height = allocation->height - 2 * border_width;
122 gtk_widget_size_allocate (child, &child_alloc);
125 gtk_widget_queue_draw (widget);
129 gtk_offscreen_window_realize (GtkWidget *widget)
131 GtkAllocation allocation;
135 GdkWindowAttr attributes;
136 gint attributes_mask;
139 bin = GTK_BIN (widget);
141 gtk_widget_set_realized (widget, TRUE);
143 border_width = gtk_container_get_border_width (GTK_CONTAINER (widget));
145 gtk_widget_get_allocation (widget, &allocation);
147 attributes.x = allocation.x;
148 attributes.y = allocation.y;
149 attributes.width = allocation.width;
150 attributes.height = allocation.height;
151 attributes.window_type = GDK_WINDOW_OFFSCREEN;
152 attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
153 attributes.visual = gtk_widget_get_visual (widget);
154 attributes.colormap = gtk_widget_get_colormap (widget);
155 attributes.wclass = GDK_INPUT_OUTPUT;
157 attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
159 window = gdk_window_new (gtk_widget_get_parent_window (widget),
160 &attributes, attributes_mask);
161 gtk_widget_set_window (widget, window);
162 gdk_window_set_user_data (window, widget);
164 child = gtk_bin_get_child (bin);
166 gtk_widget_set_parent_window (child, window);
168 gtk_widget_style_attach (widget);
169 gtk_style_set_background (gtk_widget_get_style (widget),
170 window, GTK_STATE_NORMAL);
174 gtk_offscreen_window_resize (GtkWidget *widget)
176 GtkAllocation allocation = { 0, 0 };
177 GtkRequisition requisition;
179 gtk_size_request_get_size (GTK_SIZE_REQUEST (widget),
182 allocation.width = requisition.width;
183 allocation.height = requisition.height;
184 gtk_widget_size_allocate (widget, &allocation);
188 move_focus (GtkWidget *widget,
189 GtkDirectionType dir)
191 gtk_widget_child_focus (widget, dir);
193 if (!gtk_container_get_focus_child (GTK_CONTAINER (widget)))
194 gtk_window_set_focus (GTK_WINDOW (widget), NULL);
198 gtk_offscreen_window_show (GtkWidget *widget)
200 gboolean need_resize;
201 GtkContainer *container;
203 GTK_WIDGET_SET_FLAGS (widget, GTK_VISIBLE);
205 container = GTK_CONTAINER (widget);
206 need_resize = _gtk_container_get_need_resize (container) || !gtk_widget_get_realized (widget);
207 _gtk_container_set_need_resize (container, FALSE);
210 gtk_offscreen_window_resize (widget);
212 gtk_widget_map (widget);
214 /* Try to make sure that we have some focused widget */
215 if (!gtk_window_get_focus (GTK_WINDOW (widget)))
216 move_focus (widget, GTK_DIR_TAB_FORWARD);
220 gtk_offscreen_window_hide (GtkWidget *widget)
222 GTK_WIDGET_UNSET_FLAGS (widget, GTK_VISIBLE);
223 gtk_widget_unmap (widget);
227 gtk_offscreen_window_check_resize (GtkContainer *container)
229 GtkWidget *widget = GTK_WIDGET (container);
231 if (gtk_widget_get_visible (widget))
232 gtk_offscreen_window_resize (widget);
236 gtk_offscreen_window_class_init (GtkOffscreenWindowClass *class)
238 GtkWidgetClass *widget_class;
239 GtkContainerClass *container_class;
241 widget_class = GTK_WIDGET_CLASS (class);
242 container_class = GTK_CONTAINER_CLASS (class);
244 widget_class->realize = gtk_offscreen_window_realize;
245 widget_class->show = gtk_offscreen_window_show;
246 widget_class->hide = gtk_offscreen_window_hide;
247 widget_class->size_request = gtk_offscreen_window_size_request;
248 widget_class->size_allocate = gtk_offscreen_window_size_allocate;
250 container_class->check_resize = gtk_offscreen_window_check_resize;
254 gtk_offscreen_window_init (GtkOffscreenWindow *window)
258 /* --- functions --- */
260 * gtk_offscreen_window_new:
262 * Creates a toplevel container widget that is used to retrieve
263 * snapshots of widgets without showing them on the screen. For
264 * widgets that are on the screen and part of a normal widget
265 * hierarchy, gtk_widget_get_snapshot() can be used instead.
267 * Return value: A pointer to a #GtkWidget
272 gtk_offscreen_window_new (void)
274 return g_object_new (gtk_offscreen_window_get_type (), NULL);
278 * gtk_offscreen_window_get_pixmap:
279 * @offscreen: the #GtkOffscreenWindow contained widget.
281 * Retrieves a snapshot of the contained widget in the form of
282 * a #GdkPixmap. If you need to keep this around over window
283 * resizes then you should add a reference to it.
285 * Returns: (transfer none): A #GdkPixmap pointer to the offscreen pixmap,
291 gtk_offscreen_window_get_pixmap (GtkOffscreenWindow *offscreen)
293 g_return_val_if_fail (GTK_IS_OFFSCREEN_WINDOW (offscreen), NULL);
295 return gdk_offscreen_window_get_pixmap (gtk_widget_get_window (GTK_WIDGET (offscreen)));
299 * gtk_offscreen_window_get_pixbuf:
300 * @offscreen: the #GtkOffscreenWindow contained widget.
302 * Retrieves a snapshot of the contained widget in the form of
303 * a #GdkPixbuf. This is a new pixbuf with a reference count of 1,
304 * and the application should unreference it once it is no longer
307 * Returns: (transfer full): A #GdkPixbuf pointer, or %NULL.
312 gtk_offscreen_window_get_pixbuf (GtkOffscreenWindow *offscreen)
314 GdkPixmap *pixmap = NULL;
315 GdkPixbuf *pixbuf = NULL;
317 g_return_val_if_fail (GTK_IS_OFFSCREEN_WINDOW (offscreen), NULL);
319 pixmap = gdk_offscreen_window_get_pixmap (gtk_widget_get_window (GTK_WIDGET (offscreen)));
325 gdk_drawable_get_size (pixmap, &width, &height);
327 pixbuf = gdk_pixbuf_get_from_drawable (NULL, pixmap, NULL,