gtk2/gtk/gtkspinner.c
Emmanuele Bassi c63087a563 Remove ATK
To build a better world sometimes means having to tear the old one down.
        -- Alexander Pierce, "Captain America: The Winter Soldier"

ATK served us well for nearly 20 years, but the world has changed, and
GTK has changed with it. Now ATK is mostly a hindrance towards improving
the accessibility stack:

 - it maps to a very specific implementation, AT-SPI, which is Linux and
   Unix specific
 - it requires implementing the same functionality in three different
   layers of the stack: AT-SPI, ATK, and GTK
 - only GTK uses it; every other Linux and Unix toolkit and application
   talks to AT-SPI directly, including assistive technologies

Sadly, we cannot incrementally port GTK to a new accessibility stack;
since ATK insulates us entirely from the underlying implementation, we
cannot replace it piecemeal. Instead, we're going to remove everything
and then incrementally build on a clean slate:

 - add an "accessible" interface, implemented by GTK objects directly,
   which describe the accessible role and state changes for every UI
   element
 - add an "assistive technology context" to proxy a native accessibility
   API, and assign it to every widget
 - implement the AT context depending on the platform

For more information, see: https://gitlab.gnome.org/GNOME/gtk/-/issues/2833
2020-07-26 20:31:14 +01:00

292 lines
7.7 KiB
C

/* GTK - The GIMP Toolkit
*
* Copyright (C) 2007 John Stowers, Neil Jagdish Patel.
* Copyright (C) 2009 Bastien Nocera, David Zeuthen
*
* 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/>.
*
* Code adapted from egg-spinner
* by Christian Hergert <christian.hergert@gmail.com>
*/
/*
* Modified by the GTK+ Team and others 2007. 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/.
*/
#include "config.h"
#include "gtkspinner.h"
#include "gtkimage.h"
#include "gtkintl.h"
#include "gtkprivate.h"
#include "gtkstylecontext.h"
#include "gtkstylecontextprivate.h"
#include "gtkwidgetprivate.h"
#include "gtkcssnumbervalueprivate.h"
#include "gtkrendericonprivate.h"
/**
* SECTION:gtkspinner
* @Short_description: Show a spinner animation
* @Title: GtkSpinner
* @See_also: #GtkCellRendererSpinner, #GtkProgressBar
*
* A GtkSpinner widget displays an icon-size spinning animation.
* It is often used as an alternative to a #GtkProgressBar for
* displaying indefinite activity, instead of actual progress.
*
* To start the animation, use gtk_spinner_start(), to stop it
* use gtk_spinner_stop().
*
* # CSS nodes
*
* GtkSpinner has a single CSS node with the name spinner.
* When the animation is active, the :checked pseudoclass is
* added to this node.
*/
typedef struct _GtkSpinnerClass GtkSpinnerClass;
struct _GtkSpinner
{
GtkWidget parent;
};
struct _GtkSpinnerClass
{
GtkWidgetClass parent_class;
};
enum {
PROP_0,
PROP_SPINNING
};
G_DEFINE_TYPE (GtkSpinner, gtk_spinner, GTK_TYPE_WIDGET)
#define DEFAULT_SIZE 16
static void
gtk_spinner_measure (GtkWidget *widget,
GtkOrientation orientation,
int for_size,
int *minimum,
int *natural,
int *minimum_baseline,
int *natural_baseline)
{
double min_size;
GtkCssStyle *style;
style = gtk_css_node_get_style (gtk_widget_get_css_node (widget));
if (orientation == GTK_ORIENTATION_HORIZONTAL)
min_size = _gtk_css_number_value_get (style->size->min_width, 100);
else
min_size = _gtk_css_number_value_get (style->size->min_height, 100);
if (min_size > 0.0)
*minimum = *natural = min_size;
else
*minimum = *natural = DEFAULT_SIZE;
}
static void
gtk_spinner_snapshot (GtkWidget *widget,
GtkSnapshot *snapshot)
{
GtkCssStyle *style = gtk_css_node_get_style (gtk_widget_get_css_node (widget));
gtk_css_style_snapshot_icon (style,
snapshot,
gtk_widget_get_width (widget),
gtk_widget_get_height (widget));
}
static void
gtk_spinner_css_changed (GtkWidget *widget,
GtkCssStyleChange *change)
{
GTK_WIDGET_CLASS (gtk_spinner_parent_class)->css_changed (widget, change);
if (change == NULL ||
gtk_css_style_change_affects (change, GTK_CSS_AFFECTS_ICON_SIZE))
{
gtk_widget_queue_resize (widget);
}
else if (gtk_css_style_change_affects (change, GTK_CSS_AFFECTS_ICON_TEXTURE) ||
gtk_css_style_change_affects (change, GTK_CSS_AFFECTS_ICON_REDRAW))
{
gtk_widget_queue_draw (widget);
}
}
/**
* gtk_spinner_get_spinning:
* @spinner: a #GtkSpinner
*
* Returns whether the spinner is spinning.
*
* Returns: %TRUE if the spinner is active
*/
gboolean
gtk_spinner_get_spinning (GtkSpinner *spinner)
{
g_return_val_if_fail (GTK_IS_SPINNER (spinner), FALSE);
return (gtk_widget_get_state_flags ((GtkWidget *)spinner) & GTK_STATE_FLAG_CHECKED) > 0;
}
/**
* gtk_spinner_set_spinning:
* @spinner: a #GtkSpinner
* @spinning: whether the spinner should be spinning
*
* Sets the activity of the spinner.
*/
void
gtk_spinner_set_spinning (GtkSpinner *spinner,
gboolean spinning)
{
g_return_if_fail (GTK_IS_SPINNER (spinner));
spinning = !!spinning;
if (spinning != gtk_spinner_get_spinning (spinner))
{
g_object_notify (G_OBJECT (spinner), "spinning");
if (spinning)
gtk_widget_set_state_flags (GTK_WIDGET (spinner),
GTK_STATE_FLAG_CHECKED, FALSE);
else
gtk_widget_unset_state_flags (GTK_WIDGET (spinner),
GTK_STATE_FLAG_CHECKED);
}
}
static void
gtk_spinner_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec)
{
switch (param_id)
{
case PROP_SPINNING:
g_value_set_boolean (value, gtk_spinner_get_spinning (GTK_SPINNER (object)));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
}
}
static void
gtk_spinner_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec)
{
switch (param_id)
{
case PROP_SPINNING:
gtk_spinner_set_spinning (GTK_SPINNER (object), g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
}
}
static void
gtk_spinner_class_init (GtkSpinnerClass *klass)
{
GObjectClass *gobject_class;
GtkWidgetClass *widget_class;
gobject_class = G_OBJECT_CLASS(klass);
gobject_class->get_property = gtk_spinner_get_property;
gobject_class->set_property = gtk_spinner_set_property;
widget_class = GTK_WIDGET_CLASS(klass);
widget_class->snapshot = gtk_spinner_snapshot;
widget_class->measure = gtk_spinner_measure;
widget_class->css_changed = gtk_spinner_css_changed;
/* GtkSpinner:spinning:
*
* Whether the spinner is spinning
*/
g_object_class_install_property (gobject_class,
PROP_SPINNING,
g_param_spec_boolean ("spinning",
P_("Spinning"),
P_("Whether the spinner is spinning"),
FALSE,
GTK_PARAM_READWRITE|G_PARAM_EXPLICIT_NOTIFY));
gtk_widget_class_set_css_name (widget_class, I_("spinner"));
}
static void
gtk_spinner_init (GtkSpinner *spinner)
{
}
/**
* gtk_spinner_new:
*
* Returns a new spinner widget. Not yet started.
*
* Returns: a new #GtkSpinner
*/
GtkWidget *
gtk_spinner_new (void)
{
return g_object_new (GTK_TYPE_SPINNER, NULL);
}
/**
* gtk_spinner_start:
* @spinner: a #GtkSpinner
*
* Starts the animation of the spinner.
*/
void
gtk_spinner_start (GtkSpinner *spinner)
{
g_return_if_fail (GTK_IS_SPINNER (spinner));
gtk_spinner_set_spinning (spinner, TRUE);
}
/**
* gtk_spinner_stop:
* @spinner: a #GtkSpinner
*
* Stops the animation of the spinner.
*/
void
gtk_spinner_stop (GtkSpinner *spinner)
{
g_return_if_fail (GTK_IS_SPINNER (spinner));
gtk_spinner_set_spinning (spinner, FALSE);
}