gtk2/gtk/gtkbin.c
2014-06-14 08:10:46 +02:00

334 lines
11 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* 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, 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/.
*/
/**
* SECTION:gtkbin
* @Short_description: A container with just one child
* @Title: GtkBin
*
* The #GtkBin widget is a container with just one child.
* It is not very useful itself, but it is useful for deriving subclasses,
* since it provides common code needed for handling a single child widget.
*
* Many GTK+ widgets are subclasses of #GtkBin, including #GtkWindow,
* #GtkButton, #GtkFrame, #GtkHandleBox or #GtkScrolledWindow.
*/
#include "config.h"
#include "gtkbin.h"
#include "gtksizerequest.h"
#include "gtkintl.h"
struct _GtkBinPrivate
{
GtkWidget *child;
};
static void gtk_bin_add (GtkContainer *container,
GtkWidget *widget);
static void gtk_bin_remove (GtkContainer *container,
GtkWidget *widget);
static void gtk_bin_forall (GtkContainer *container,
gboolean include_internals,
GtkCallback callback,
gpointer callback_data);
static GType gtk_bin_child_type (GtkContainer *container);
static void gtk_bin_get_preferred_width (GtkWidget *widget,
gint *minimum_width,
gint *natural_width);
static void gtk_bin_get_preferred_height (GtkWidget *widget,
gint *minimum_height,
gint *natural_height);
static void gtk_bin_get_preferred_width_for_height (GtkWidget *widget,
gint height,
gint *minimum_width,
gint *natural_width);
static void gtk_bin_get_preferred_height_for_width (GtkWidget *widget,
gint width,
gint *minimum_height,
gint *natural_height);
static void gtk_bin_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GtkBin, gtk_bin, GTK_TYPE_CONTAINER)
static void
gtk_bin_class_init (GtkBinClass *class)
{
GtkWidgetClass *widget_class = (GtkWidgetClass*) class;
GtkContainerClass *container_class = (GtkContainerClass*) class;
widget_class->get_preferred_width = gtk_bin_get_preferred_width;
widget_class->get_preferred_height = gtk_bin_get_preferred_height;
widget_class->get_preferred_width_for_height = gtk_bin_get_preferred_width_for_height;
widget_class->get_preferred_height_for_width = gtk_bin_get_preferred_height_for_width;
widget_class->size_allocate = gtk_bin_size_allocate;
container_class->add = gtk_bin_add;
container_class->remove = gtk_bin_remove;
container_class->forall = gtk_bin_forall;
container_class->child_type = gtk_bin_child_type;
}
static void
gtk_bin_init (GtkBin *bin)
{
bin->priv = gtk_bin_get_instance_private (bin);
gtk_widget_set_has_window (GTK_WIDGET (bin), FALSE);
}
static GType
gtk_bin_child_type (GtkContainer *container)
{
GtkBinPrivate *priv = GTK_BIN (container)->priv;
if (!priv->child)
return GTK_TYPE_WIDGET;
else
return G_TYPE_NONE;
}
static void
gtk_bin_add (GtkContainer *container,
GtkWidget *child)
{
GtkBin *bin = GTK_BIN (container);
GtkBinPrivate *priv = bin->priv;
if (priv->child != NULL)
{
g_warning ("Attempting to add a widget with type %s to a %s, "
"but as a GtkBin subclass a %s can only contain one widget at a time; "
"it already contains a widget of type %s",
g_type_name (G_OBJECT_TYPE (child)),
g_type_name (G_OBJECT_TYPE (bin)),
g_type_name (G_OBJECT_TYPE (bin)),
g_type_name (G_OBJECT_TYPE (priv->child)));
return;
}
gtk_widget_set_parent (child, GTK_WIDGET (bin));
priv->child = child;
}
static void
gtk_bin_remove (GtkContainer *container,
GtkWidget *child)
{
GtkBin *bin = GTK_BIN (container);
GtkBinPrivate *priv = bin->priv;
gboolean widget_was_visible;
g_return_if_fail (priv->child == child);
widget_was_visible = gtk_widget_get_visible (child);
gtk_widget_unparent (child);
priv->child = NULL;
/* queue resize regardless of gtk_widget_get_visible (container),
* since that's what is needed by toplevels, which derive from GtkBin.
*/
if (widget_was_visible)
gtk_widget_queue_resize (GTK_WIDGET (container));
}
static void
gtk_bin_forall (GtkContainer *container,
gboolean include_internals,
GtkCallback callback,
gpointer callback_data)
{
GtkBin *bin = GTK_BIN (container);
GtkBinPrivate *priv = bin->priv;
if (priv->child)
(* callback) (priv->child, callback_data);
}
static int
gtk_bin_get_effective_border_width (GtkBin *bin)
{
if (GTK_CONTAINER_CLASS (GTK_BIN_GET_CLASS (bin))->_handle_border_width)
return 0;
return gtk_container_get_border_width (GTK_CONTAINER (bin));
}
static void
gtk_bin_get_preferred_width (GtkWidget *widget,
gint *minimum_width,
gint *natural_width)
{
GtkBin *bin = GTK_BIN (widget);
GtkBinPrivate *priv = bin->priv;
gint border_width;
*minimum_width = 0;
*natural_width = 0;
if (priv->child && gtk_widget_get_visible (priv->child))
{
gint child_min, child_nat;
gtk_widget_get_preferred_width (priv->child,
&child_min, &child_nat);
*minimum_width = child_min;
*natural_width = child_nat;
}
border_width = gtk_bin_get_effective_border_width (bin);
*minimum_width += 2 * border_width;
*natural_width += 2 * border_width;
}
static void
gtk_bin_get_preferred_height (GtkWidget *widget,
gint *minimum_height,
gint *natural_height)
{
GtkBin *bin = GTK_BIN (widget);
GtkBinPrivate *priv = bin->priv;
gint border_width;
*minimum_height = 0;
*natural_height = 0;
if (priv->child && gtk_widget_get_visible (priv->child))
{
gint child_min, child_nat;
gtk_widget_get_preferred_height (priv->child,
&child_min, &child_nat);
*minimum_height = child_min;
*natural_height = child_nat;
}
border_width = gtk_bin_get_effective_border_width (bin);
*minimum_height += 2 * border_width;
*natural_height += 2 * border_width;
}
static void
gtk_bin_get_preferred_width_for_height (GtkWidget *widget,
gint height,
gint *minimum_width,
gint *natural_width)
{
GtkBin *bin = GTK_BIN (widget);
GtkBinPrivate *priv = bin->priv;
gint border_width;
*minimum_width = 0;
*natural_width = 0;
border_width = gtk_bin_get_effective_border_width (bin);
if (priv->child && gtk_widget_get_visible (priv->child))
{
gint child_min, child_nat;
gtk_widget_get_preferred_width_for_height (priv->child, height - 2 * border_width,
&child_min, &child_nat);
*minimum_width = child_min;
*natural_width = child_nat;
}
*minimum_width += 2 * border_width;
*natural_width += 2 * border_width;
}
static void
gtk_bin_get_preferred_height_for_width (GtkWidget *widget,
gint width,
gint *minimum_height,
gint *natural_height)
{
GtkBin *bin = GTK_BIN (widget);
GtkBinPrivate *priv = bin->priv;
gint border_width;
*minimum_height = 0;
*natural_height = 0;
border_width = gtk_bin_get_effective_border_width (bin);
if (priv->child && gtk_widget_get_visible (priv->child))
{
gint child_min, child_nat;
gtk_widget_get_preferred_height_for_width (priv->child, width - 2 * border_width,
&child_min, &child_nat);
*minimum_height = child_min;
*natural_height = child_nat;
}
*minimum_height += 2 * border_width;
*natural_height += 2 * border_width;
}
static void
gtk_bin_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkBin *bin = GTK_BIN (widget);
GtkBinPrivate *priv = bin->priv;
gtk_widget_set_allocation (widget, allocation);
if (priv->child && gtk_widget_get_visible (priv->child))
{
GtkAllocation child_allocation;
gint border_width = gtk_bin_get_effective_border_width (bin);
child_allocation.x = allocation->x + border_width;
child_allocation.y = allocation->y + border_width;
child_allocation.width = allocation->width - 2 * border_width;
child_allocation.height = allocation->height - 2 * border_width;
gtk_widget_size_allocate (priv->child, &child_allocation);
}
}
/**
* gtk_bin_get_child:
* @bin: a #GtkBin
*
* Gets the child of the #GtkBin, or %NULL if the bin contains
* no child widget. The returned widget does not have a reference
* added, so you do not need to unref it.
*
* Returns: (transfer none): pointer to child of the #GtkBin
**/
GtkWidget*
gtk_bin_get_child (GtkBin *bin)
{
g_return_val_if_fail (GTK_IS_BIN (bin), NULL);
return bin->priv->child;
}