* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
- * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
+ * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
#include "config.h"
#include "gtkdrawingarea.h"
#include "gtkintl.h"
+#include "gtkstylecontext.h"
+/**
+ * SECTION:gtkdrawingarea
+ * @Short_description: A widget for custom user interface elements
+ * @Title: GtkDrawingArea
+ * @See_also: #GtkImage
+ *
+ * The #GtkDrawingArea widget is used for creating custom user interface
+ * elements. It's essentially a blank widget; you can draw on it. After
+ * creating a drawing area, the application may want to connect to:
+ *
+ * <itemizedlist>
+ * <listitem>
+ * <para>
+ * Mouse and button press signals to respond to input from
+ * the user. (Use gtk_widget_add_events() to enable events
+ * you wish to receive.)
+ * </para>
+ * </listitem>
+ * <listitem>
+ * <para>
+ * The #GtkWidget::realize signal to take any necessary actions
+ * when the widget is instantiated on a particular display.
+ * (Create GDK resources in response to this signal.)
+ * </para>
+ * </listitem>
+ * <listitem>
+ * <para>
+ * The #GtkWidget::configure-event signal to take any necessary
+ * actions when the widget changes size.
+ * </para>
+ * </listitem>
+ * <listitem>
+ * <para>
+ * The #GtkWidget::draw signal to handle redrawing the
+ * contents of the widget.
+ * </para>
+ * </listitem>
+ * </itemizedlist>
+ *
+ * The following code portion demonstrates using a drawing
+ * area to display a circle in the normal widget foreground
+ * color.
+ *
+ * Note that GDK automatically clears the exposed area to the
+ * background color before sending the expose event, and that
+ * drawing is implicitly clipped to the exposed area.
+ *
+ * <example>
+ * <title>Simple GtkDrawingArea usage</title>
+ * <programlisting>
+ * gboolean
+ * draw_callback (GtkWidget *widget, cairo_t *cr, gpointer data)
+ * {
+ * guint width, height;
+ * GdkRGBA color;
+ *
+ * width = gtk_widget_get_allocated_width (widget);
+ * height = gtk_widget_get_allocated_height (widget);
+ * cairo_arc (cr,
+ * width / 2.0, height / 2.0,
+ * MIN (width, height) / 2.0,
+ * 0, 2 * G_PI);
+ *
+ * gtk_style_context_get_color (gtk_widget_get_style_context (widget),
+ * 0,
+ * &color);
+ * gdk_cairo_set_source_rgba (cr, &color);
+ *
+ * cairo_fill (cr);
+ *
+ * return FALSE;
+ * }
+ * [...]
+ * GtkWidget *drawing_area = gtk_drawing_area_new (<!-- -->);
+ * gtk_widget_set_size_request (drawing_area, 100, 100);
+ * g_signal_connect (G_OBJECT (drawing_area), "draw",
+ * G_CALLBACK (draw_callback), NULL);
+ * </programlisting>
+ * </example>
+ *
+ * Draw signals are normally delivered when a drawing area first comes
+ * onscreen, or when it's covered by another window and then uncovered.
+ * You can also force an expose event by adding to the "damage region"
+ * of the drawing area's window; gtk_widget_queue_draw_area() and
+ * gdk_window_invalidate_rect() are equally good ways to do this.
+ * You'll then get a draw signal for the invalid region.
+ *
+ * The available routines for drawing are documented on the <link
+ * linkend="gdk3-Cairo-Interaction">GDK Drawing Primitives</link> page
+ * and the cairo documentation.
+ *
+ * To receive mouse events on a drawing area, you will need to enable
+ * them with gtk_widget_add_events(). To receive keyboard events, you
+ * will need to set the "can-focus" property on the drawing area, and you
+ * should probably draw some user-visible indication that the drawing
+ * area is focused. Use gtk_widget_has_focus() in your expose event
+ * handler to decide whether to draw the focus indicator. See
+ * gtk_render_focus() for one way to draw focus.
+ */
+
static void gtk_drawing_area_realize (GtkWidget *widget);
static void gtk_drawing_area_size_allocate (GtkWidget *widget,
- GtkAllocation *allocation);
+ GtkAllocation *allocation);
static void gtk_drawing_area_send_configure (GtkDrawingArea *darea);
G_DEFINE_TYPE (GtkDrawingArea, gtk_drawing_area, GTK_TYPE_WIDGET)
static void
gtk_drawing_area_init (GtkDrawingArea *darea)
{
- darea->draw_data = NULL;
}
-
+/**
+ * gtk_drawing_area_new:
+ *
+ * Creates a new drawing area.
+ *
+ * Returns: a new #GtkDrawingArea
+ */
GtkWidget*
gtk_drawing_area_new (void)
{
static void
gtk_drawing_area_realize (GtkWidget *widget)
{
- GtkDrawingArea *darea = GTK_DRAWING_AREA (widget);
GtkAllocation allocation;
GdkWindow *window;
GdkWindowAttr attributes;
attributes.height = allocation.height;
attributes.wclass = GDK_INPUT_OUTPUT;
attributes.visual = gtk_widget_get_visual (widget);
- attributes.colormap = gtk_widget_get_colormap (widget);
attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
- attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP;
+ attributes_mask = GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL;
window = gdk_window_new (gtk_widget_get_parent_window (widget),
&attributes, attributes_mask);
- gdk_window_set_user_data (window, darea);
+ gtk_widget_register_window (widget, window);
gtk_widget_set_window (widget, window);
- gtk_widget_style_attach (widget);
- gtk_style_set_background (gtk_widget_get_style (widget), window, GTK_STATE_NORMAL);
+ gtk_style_context_set_background (gtk_widget_get_style_context (widget),
+ window);
}
gtk_drawing_area_send_configure (GTK_DRAWING_AREA (widget));
static void
gtk_drawing_area_size_allocate (GtkWidget *widget,
- GtkAllocation *allocation)
+ GtkAllocation *allocation)
{
g_return_if_fail (GTK_IS_DRAWING_AREA (widget));
g_return_if_fail (allocation != NULL);
event->configure.y = allocation.y;
event->configure.width = allocation.width;
event->configure.height = allocation.height;
-
+
gtk_widget_event (widget, event);
gdk_event_free (event);
}
projects / ~andy / gtk / blobdiff