Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
branch: windows
Fetching contributors…

Cannot retrieve contributors at this time

636 lines (531 sloc) 18.384 kb
/*
* gtkoverlay.c
* This file is part of gtk
*
* Copyright (C) 2011 - Ignacio Casal Quinteiro, Mike Krüger
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* 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.
*/
#include "config.h"
#include "gtkoverlay.h"
#include "gtkbuildable.h"
#include "gtkscrolledwindow.h"
#include "gtkmainprivate.h"
#include "gtkmarshalers.h"
#include "gtkprivate.h"
#include "gtkintl.h"
/**
* SECTION:gtkoverlay
* @short_description: A container which overlays widgets on top of each other
* @title: GtkOverlay
*
* GtkOverlay is a container which contains a single main child, on top
* of which it can place <firstterm>overlay</firstterm> widgets. The
* position of each overlay widget is determined by its #GtkWidget::halign
* and #GtkWidget::valign properties. E.g. a widget with both alignments
* set to %GTK_ALIGN_START will be placed at the top left corner of the
* main widget, whereas an overlay with halign set to %GTK_ALIGN_CENTER
* and valign set to %GTK_ALIGN_END will be placed a the bottom edge of
* the main widget, horizontally centered. The position can be adjusted
* by setting the margin properties of the child to non-zero values.
*
* More complicated placement of overlays is possible by connecting
* to the #GtkOverlay::get-child-position signal.
*
* <refsect2 id="GtkOverlay-BUILDER-UI">
* <title>GtkOverlay as GtkBuildable</title>
* <para>
* The GtkOverlay implementation of the GtkBuildable interface
* supports placing a child as an overlay by specifying "overlay" as
* the "type" attribute of a <tag class="starttag">child</tag> element.
* </para>
* </refsect2>
*/
struct _GtkOverlayPrivate
{
GSList *children;
};
typedef struct _GtkOverlayChild GtkOverlayChild;
struct _GtkOverlayChild
{
GtkWidget *widget;
GdkWindow *window;
};
enum {
GET_CHILD_POSITION,
LAST_SIGNAL
};
static guint signals[LAST_SIGNAL] = { 0 };
static void gtk_overlay_buildable_init (GtkBuildableIface *iface);
G_DEFINE_TYPE_WITH_CODE (GtkOverlay, gtk_overlay, GTK_TYPE_BIN,
G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE,
gtk_overlay_buildable_init))
static GdkWindow *
gtk_overlay_create_child_window (GtkOverlay *overlay,
GtkWidget *child)
{
GtkWidget *widget = GTK_WIDGET (overlay);
GtkAllocation allocation;
GdkWindow *window;
GdkWindowAttr attributes;
gint attributes_mask;
gtk_widget_get_allocation (child, &allocation);
attributes.window_type = GDK_WINDOW_CHILD;
attributes.wclass = GDK_INPUT_OUTPUT;
attributes.width = allocation.width;
attributes.height = allocation.height;
attributes.x = allocation.x;
attributes.y = allocation.y;
attributes_mask = GDK_WA_X | GDK_WA_Y;
attributes.event_mask = gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
window = gdk_window_new (gtk_widget_get_window (widget),
&attributes, attributes_mask);
gdk_window_set_user_data (window, overlay);
gtk_style_context_set_background (gtk_widget_get_style_context (widget), window);
gtk_widget_set_parent_window (child, window);
return window;
}
static void
gtk_overlay_child_allocate (GtkOverlayChild *child,
GtkAllocation *allocation)
{
gint left, right, top, bottom;
GtkAllocation child_allocation;
/* put the margins outside the window; also arrange things
* so that the adjusted child allocation still ends up at 0, 0
*/
left = gtk_widget_get_margin_left (child->widget);
right = gtk_widget_get_margin_right (child->widget);
top = gtk_widget_get_margin_top (child->widget);
bottom = gtk_widget_get_margin_bottom (child->widget);
child_allocation.x = - left;
child_allocation.y = - top;
child_allocation.width = allocation->width;
child_allocation.height = allocation->height;
allocation->x += left;
allocation->y += top;
allocation->width -= left + right;
allocation->height -= top + bottom;
if (child->window)
gdk_window_move_resize (child->window,
allocation->x, allocation->y,
allocation->width, allocation->height);
gtk_widget_size_allocate (child->widget, &child_allocation);
}
static void
gtk_overlay_get_preferred_width (GtkWidget *widget,
gint *minimum,
gint *natural)
{
GtkBin *bin = GTK_BIN (widget);
GtkWidget *child;
if (minimum)
*minimum = 0;
if (natural)
*natural = 0;
child = gtk_bin_get_child (bin);
if (child && gtk_widget_get_visible (child))
gtk_widget_get_preferred_width (child, minimum, natural);
}
static void
gtk_overlay_get_preferred_height (GtkWidget *widget,
gint *minimum,
gint *natural)
{
GtkBin *bin = GTK_BIN (widget);
GtkWidget *child;
if (minimum)
*minimum = 0;
if (natural)
*natural = 0;
child = gtk_bin_get_child (bin);
if (child && gtk_widget_get_visible (child))
gtk_widget_get_preferred_height (child, minimum, natural);
}
static void
gtk_overlay_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GSList *children;
GtkWidget *main_widget;
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->size_allocate (widget, allocation);
main_widget = gtk_bin_get_child (GTK_BIN (overlay));
if (!main_widget || !gtk_widget_get_visible (main_widget))
return;
gtk_widget_size_allocate (main_widget, allocation);
for (children = priv->children; children; children = children->next)
{
GtkOverlayChild *child;
GtkAllocation alloc;
gboolean result;
child = children->data;
if (gtk_widget_get_mapped (GTK_WIDGET (overlay)))
{
if (gtk_widget_get_visible (child->widget))
gdk_window_show (child->window);
else if (gdk_window_is_visible (child->window))
gdk_window_hide (child->window);
}
if (!gtk_widget_get_visible (child->widget))
continue;
g_signal_emit (overlay, signals[GET_CHILD_POSITION],
0, child->widget, &alloc, &result);
alloc.x += allocation->x;
alloc.y += allocation->y;
gtk_overlay_child_allocate (child, &alloc);
}
}
static GtkAlign
effective_align (GtkAlign align,
GtkTextDirection direction)
{
switch (align)
{
case GTK_ALIGN_START:
return direction == GTK_TEXT_DIR_RTL ? GTK_ALIGN_END : GTK_ALIGN_START;
case GTK_ALIGN_END:
return direction == GTK_TEXT_DIR_RTL ? GTK_ALIGN_START : GTK_ALIGN_END;
default:
return align;
}
}
static gboolean
gtk_overlay_get_child_position (GtkOverlay *overlay,
GtkWidget *widget,
GtkAllocation *alloc)
{
GtkWidget *main_widget;
GtkAllocation main_alloc;
GtkRequisition req;
GtkAlign halign;
GtkTextDirection direction;
main_widget = gtk_bin_get_child (GTK_BIN (overlay));
/* special-case scrolled windows */
if (GTK_IS_SCROLLED_WINDOW (main_widget))
{
GtkWidget *grandchild;
gint x, y;
grandchild = gtk_bin_get_child (GTK_BIN (main_widget));
gtk_widget_translate_coordinates (grandchild, main_widget, 0, 0, &x, &y);
main_alloc.x = x;
main_alloc.y = y;
main_alloc.width = gtk_widget_get_allocated_width (grandchild);
main_alloc.height = gtk_widget_get_allocated_height (grandchild);
}
else
{
main_alloc.x = 0;
main_alloc.y = 0;
main_alloc.width = gtk_widget_get_allocated_width (main_widget);
main_alloc.height = gtk_widget_get_allocated_height (main_widget);
}
gtk_widget_get_preferred_size (widget, NULL, &req);
alloc->x = main_alloc.x;
alloc->width = MIN (main_alloc.width, req.width);
direction = gtk_widget_get_direction (widget);
halign = gtk_widget_get_halign (widget);
switch (effective_align (halign, direction))
{
case GTK_ALIGN_START:
/* nothing to do */
break;
case GTK_ALIGN_FILL:
alloc->width = main_alloc.width;
break;
case GTK_ALIGN_CENTER:
alloc->x += main_alloc.width / 2 - req.width / 2;
break;
case GTK_ALIGN_END:
alloc->x += main_alloc.width - req.width;
break;
}
alloc->y = main_alloc.y;
alloc->height = MIN (main_alloc.height, req.height);
switch (gtk_widget_get_valign (widget))
{
case GTK_ALIGN_START:
/* nothing to do */
break;
case GTK_ALIGN_FILL:
alloc->height = main_alloc.height;
break;
case GTK_ALIGN_CENTER:
alloc->y += main_alloc.height / 2 - req.height / 2;
break;
case GTK_ALIGN_END:
alloc->y += main_alloc.height - req.height;
break;
}
return TRUE;
}
static void
gtk_overlay_realize (GtkWidget *widget)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
GSList *children;
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->realize (widget);
for (children = priv->children; children; children = children->next)
{
child = children->data;
if (child->window == NULL)
child->window = gtk_overlay_create_child_window (overlay, child->widget);
}
}
static void
gtk_overlay_unrealize (GtkWidget *widget)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
GSList *children;
for (children = priv->children; children; children = children->next)
{
child = children->data;
gtk_widget_set_parent_window (child->widget, NULL);
gdk_window_set_user_data (child->window, NULL);
gdk_window_destroy (child->window);
child->window = NULL;
}
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->unrealize (widget);
}
static void
gtk_overlay_map (GtkWidget *widget)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
GSList *children;
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->map (widget);
for (children = priv->children; children; children = children->next)
{
child = children->data;
if (child->window != NULL &&
gtk_widget_get_visible (child->widget) &&
gtk_widget_get_child_visible (child->widget))
gdk_window_show (child->window);
}
}
static void
gtk_overlay_unmap (GtkWidget *widget)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
GSList *children;
for (children = priv->children; children; children = children->next)
{
child = children->data;
if (child->window != NULL &&
gdk_window_is_visible (child->window))
gdk_window_hide (child->window);
}
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->unmap (widget);
}
static gboolean
gtk_overlay_draw (GtkWidget *widget,
cairo_t *cr)
{
GtkOverlay *overlay = GTK_OVERLAY (widget);
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
GSList *children;
for (children = priv->children; children; children = children->next)
{
child = children->data;
if (gtk_cairo_should_draw_window (cr, child->window))
{
cairo_save (cr);
gtk_cairo_transform_to_window (cr, widget, child->window);
gtk_render_background (gtk_widget_get_style_context (widget),
cr,
0, 0,
gdk_window_get_width (child->window),
gdk_window_get_height (child->window));
cairo_restore (cr);
}
}
GTK_WIDGET_CLASS (gtk_overlay_parent_class)->draw (widget, cr);
return FALSE;
}
static void
gtk_overlay_remove (GtkContainer *container,
GtkWidget *widget)
{
GtkOverlayPrivate *priv = GTK_OVERLAY (container)->priv;
GtkOverlayChild *child;
GSList *children;
for (children = priv->children; children; children = children->next)
{
child = children->data;
if (child->widget == widget)
{
if (child->window != NULL)
{
gdk_window_set_user_data (child->window, NULL);
gdk_window_destroy (child->window);
}
gtk_widget_unparent (widget);
priv->children = g_slist_delete_link (priv->children, children);
g_slice_free (GtkOverlayChild, child);
return;
}
}
GTK_CONTAINER_CLASS (gtk_overlay_parent_class)->remove (container, widget);
}
static void
gtk_overlay_forall (GtkContainer *overlay,
gboolean include_internals,
GtkCallback callback,
gpointer callback_data)
{
GtkOverlayPrivate *priv = GTK_OVERLAY (overlay)->priv;
GtkOverlayChild *child;
GSList *children;
GtkWidget *main_widget;
main_widget = gtk_bin_get_child (GTK_BIN (overlay));
if (main_widget)
(* callback) (main_widget, callback_data);
children = priv->children;
while (children)
{
child = children->data;
children = children->next;
(* callback) (child->widget, callback_data);
}
}
static void
gtk_overlay_class_init (GtkOverlayClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
GtkContainerClass *container_class = GTK_CONTAINER_CLASS (klass);
widget_class->get_preferred_width = gtk_overlay_get_preferred_width;
widget_class->get_preferred_height = gtk_overlay_get_preferred_height;
widget_class->size_allocate = gtk_overlay_size_allocate;
widget_class->realize = gtk_overlay_realize;
widget_class->unrealize = gtk_overlay_unrealize;
widget_class->map = gtk_overlay_map;
widget_class->unmap = gtk_overlay_unmap;
widget_class->draw = gtk_overlay_draw;
container_class->remove = gtk_overlay_remove;
container_class->forall = gtk_overlay_forall;
klass->get_child_position = gtk_overlay_get_child_position;
/**
* GtkOverlay::get-child-position:
* @overlay: the #GtkOverlay
* @widget: the child widget to position
* @allocation: (out): return location for the allocation
*
* The ::get-child-position signal is emitted to determine
* the position and size of any overlay child widgets. A
* handler for this signal should fill @allocation with
* the desired position and size for @widget, relative to
* the 'main' child of @overlay.
*
* The default handler for this signal uses the @widget's
* halign and valign properties to determine the position
* and gives the widget its natural size (except that an
* alignment of %GTK_ALIGN_FILL will cause the overlay to
* be full-width/height). If the main child is a
* #GtkScrolledWindow, the overlays are placed relative
* to its contents.
*
* Return: %TRUE if the @allocation has been filled
*/
signals[GET_CHILD_POSITION] =
g_signal_new (I_("get-child-position"),
G_TYPE_FROM_CLASS (object_class),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GtkOverlayClass, get_child_position),
_gtk_boolean_handled_accumulator, NULL,
_gtk_marshal_BOOLEAN__OBJECT_BOXED,
G_TYPE_BOOLEAN, 2,
GTK_TYPE_WIDGET,
GDK_TYPE_RECTANGLE | G_SIGNAL_TYPE_STATIC_SCOPE);
g_type_class_add_private (object_class, sizeof (GtkOverlayPrivate));
}
static void
gtk_overlay_init (GtkOverlay *overlay)
{
overlay->priv = G_TYPE_INSTANCE_GET_PRIVATE (overlay, GTK_TYPE_OVERLAY, GtkOverlayPrivate);
gtk_widget_set_has_window (GTK_WIDGET (overlay), FALSE);
}
static void
gtk_overlay_buildable_add_child (GtkBuildable *buildable,
GtkBuilder *builder,
GObject *child,
const gchar *type)
{
if (type && strcmp (type, "overlay") == 0)
gtk_overlay_add_overlay (GTK_OVERLAY (buildable), GTK_WIDGET (child));
else if (!type)
gtk_container_add (GTK_CONTAINER (buildable), GTK_WIDGET (child));
else
GTK_BUILDER_WARN_INVALID_CHILD_TYPE (buildable, type);
}
static void
gtk_overlay_buildable_init (GtkBuildableIface *iface)
{
iface->add_child = gtk_overlay_buildable_add_child;
}
/**
* gtk_overlay_new:
*
* Creates a new #GtkOverlay.
*
* Returns: a new #GtkOverlay object.
*
* Since: 3.2
*/
GtkWidget *
gtk_overlay_new (void)
{
return g_object_new (GTK_TYPE_OVERLAY, NULL);
}
/**
* gtk_overlay_add_overlay:
* @overlay: a #GtkOverlay
* @widget: a #GtkWidget to be added to the container
*
* Adds @widget to @overlay.
*
* The widget will be stacked on top of the main widget
* added with gtk_container_add().
*
* The position at which @widget is placed is determined
* from its #GtkWidget::halign and #GtkWidget::valign properties.
*
* Since: 3.2
*/
void
gtk_overlay_add_overlay (GtkOverlay *overlay,
GtkWidget *widget)
{
GtkOverlayPrivate *priv = overlay->priv;
GtkOverlayChild *child;
g_return_if_fail (GTK_IS_OVERLAY (overlay));
g_return_if_fail (GTK_IS_WIDGET (widget));
child = g_slice_new0 (GtkOverlayChild);
child->widget = widget;
gtk_widget_set_parent (widget, GTK_WIDGET (overlay));
priv->children = g_slist_append (priv->children, child);
if (gtk_widget_get_realized (GTK_WIDGET (overlay)))
child->window = gtk_overlay_create_child_window (overlay, widget);
}
Jump to Line
Something went wrong with that request. Please try again.