forked from AuroraMiddleware/gtk
99 lines
3.5 KiB
C
99 lines
3.5 KiB
C
/* gtkaccessiblerange.c: Accessible range interface
|
|
*
|
|
* Copyright © 2022 Red Hat Inc.
|
|
*
|
|
* SPDX-License-Identifier: LGPL-2.1-or-later
|
|
*
|
|
* 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 2.1 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/>.
|
|
*/
|
|
|
|
/**
|
|
* GtkAccessibleRange:
|
|
*
|
|
* This interface describes range controls, e. g. controls which have a single
|
|
* value which can optionally be changed by the user.
|
|
*
|
|
* This interface is expected to be implemented by controls of the
|
|
* %GTK_ACCESSIBLE_ROLE_METER, %GTK_ACCESSIBLE_ROLE_PROGRESS_BAR,
|
|
* %GTK_ACCESSIBLE_ROLE_SCROLLBAR, %GTK_ACCESSIBLE_ROLE_SLIDER and %GTK_ACCESSIBLE_ROLE_SPIN_BUTTON
|
|
* role. If that is not the case, a warning will be issued at runtime.
|
|
*
|
|
* In addition to this interface, its implementors are expected to provide the
|
|
* correct values for the following properties: %GTK_ACCESSIBLE_PROPERTY_VALUE_MAX,
|
|
* %GTK_ACCESSIBLE_PROPERTY_VALUE_MIN and %GTK_ACCESSIBLE_PROPERTY_VALUE_NOW.
|
|
*
|
|
* For controls where a minimum increment makes no sense and which do not allow
|
|
* setting the current value from the user, the default implementation of this
|
|
* interface suffices.
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include "gtkaccessiblerange.h"
|
|
|
|
G_DEFINE_INTERFACE (GtkAccessibleRange, gtk_accessible_range, GTK_TYPE_ACCESSIBLE)
|
|
|
|
static double
|
|
gtk_accessible_range_default_get_minimum_increment (GtkAccessibleRange *accessible_range)
|
|
{
|
|
return 0.0;
|
|
}
|
|
|
|
static gboolean
|
|
gtk_accessible_range_default_set_current_value (GtkAccessibleRange *accessible_range, double value)
|
|
{
|
|
return FALSE;
|
|
}
|
|
|
|
static void
|
|
gtk_accessible_range_default_init (GtkAccessibleRangeInterface *iface)
|
|
{
|
|
iface->get_minimum_increment = gtk_accessible_range_default_get_minimum_increment;
|
|
iface->set_current_value = gtk_accessible_range_default_set_current_value;
|
|
}
|
|
|
|
/*
|
|
* gtk_accessible_range_get_minimum_increment:
|
|
* @self: a `GtkAccessibleRange`
|
|
*
|
|
* Returns the minimum increment which this `GtkAccessibleRange` supports.
|
|
*
|
|
* Returns: the minimum increment, or 0.0 if not overridden
|
|
*/
|
|
double
|
|
gtk_accessible_range_get_minimum_increment (GtkAccessibleRange *self)
|
|
{
|
|
g_return_val_if_fail (GTK_IS_ACCESSIBLE_RANGE (self), .0);
|
|
|
|
return GTK_ACCESSIBLE_RANGE_GET_IFACE (self)->get_minimum_increment (self);
|
|
}
|
|
|
|
/*
|
|
* gtk_accessible_range_set_current_value:
|
|
* @self: a `GtkAccessibleRange`
|
|
*
|
|
* Sets the current value of this `GtkAccessibleRange`.
|
|
* Note that for some widgets implementing this interface, setting a value
|
|
* through the accessibility API makes no sense, so calling this function may
|
|
* in some cases do nothing.
|
|
* @returns: %true if the call changed the value, %false otherwise
|
|
*/
|
|
gboolean
|
|
gtk_accessible_range_set_current_value (GtkAccessibleRange *self, double value)
|
|
{
|
|
g_return_val_if_fail (GTK_IS_ACCESSIBLE_RANGE (self), FALSE);
|
|
|
|
GtkAccessibleRangeInterface *iface = GTK_ACCESSIBLE_RANGE_GET_IFACE (self);
|
|
return iface->set_current_value (self, value);
|
|
} |