gtk2/gtk/gtktogglebutton.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/. 
 */

#include "config.h"

#include "gtktogglebutton.h"

#include "gtkbuttonprivate.h"
#include "gtklabel.h"
#include "gtkmain.h"
#include "gtkmarshalers.h"
#include "gtktoggleaction.h"
#include "gtkactivatable.h"
#include "gtkprivate.h"
#include "gtkintl.h"
#include "a11y/gtktogglebuttonaccessible.h"


/**
 * SECTION:gtktogglebutton
 * @Short_description: Create buttons which retain their state
 * @Title: GtkToggleButton
 * @See_also: #GtkButton, #GtkCheckButton, #GtkCheckMenuItem
 *
 * A #GtkToggleButton is a #GtkButton which will remain 'pressed-in' when
 * clicked. Clicking again will cause the toggle button to return to its
 * normal state.
 *
 * A toggle button is created by calling either gtk_toggle_button_new() or
 * gtk_toggle_button_new_with_label(). If using the former, it is advisable to
 * pack a widget, (such as a #GtkLabel and/or a #GtkImage), into the toggle
 * button's container. (See #GtkButton for more information).
 *
 * The state of a #GtkToggleButton can be set specifically using
 * gtk_toggle_button_set_active(), and retrieved using
 * gtk_toggle_button_get_active().
 *
 * To simply switch the state of a toggle button, use gtk_toggle_button_toggled().
 *
 * <example>
 * <title>Creating two #GtkToggleButton widgets.</title>
 * <programlisting>
 * void make_toggles (void) {
 *    GtkWidget *dialog, *toggle1, *toggle2;
 *
 *    dialog = gtk_dialog_new (<!-- -->);
 *    toggle1 = gtk_toggle_button_new_with_label ("Hi, i'm a toggle button.");
 *
 *    // Makes this toggle button invisible
 *    gtk_toggle_button_set_mode (GTK_TOGGLE_BUTTON (toggle1), TRUE);
 *
 *    g_signal_connect (toggle1, "toggled",
 *                      G_CALLBACK (output_state), NULL);
 *    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->action_area),
 *                        toggle1, FALSE, FALSE, 2);
 *
 *    toggle2 = gtk_toggle_button_new_with_label ("Hi, i'm another toggle button.");
 *    gtk_toggle_button_set_mode (GTK_TOGGLE_BUTTON (toggle2), FALSE);
 *    g_signal_connect (toggle2, "toggled",
 *                      G_CALLBACK (output_state), NULL);
 *    gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->action_area),
 *                        toggle2, FALSE, FALSE, 2);
 *
 *    gtk_widget_show_all (dialog);
 * }
 * </programlisting>
 * </example>
 */


#define DEFAULT_LEFT_POS  4
#define DEFAULT_TOP_POS   4
#define DEFAULT_SPACING   7

struct _GtkToggleButtonPrivate
{
  guint active         : 1;
  guint draw_indicator : 1;
  guint inconsistent   : 1;
};

enum {
  TOGGLED,
  LAST_SIGNAL
};

enum {
  PROP_0,
  PROP_ACTIVE,
  PROP_INCONSISTENT,
  PROP_DRAW_INDICATOR
};


static gboolean gtk_toggle_button_mnemonic_activate  (GtkWidget            *widget,
                                                      gboolean              group_cycling);
static void gtk_toggle_button_pressed       (GtkButton            *button);
static void gtk_toggle_button_released      (GtkButton            *button);
static void gtk_toggle_button_clicked       (GtkButton            *button);
static void gtk_toggle_button_set_property  (GObject              *object,
					     guint                 prop_id,
					     const GValue         *value,
					     GParamSpec           *pspec);
static void gtk_toggle_button_get_property  (GObject              *object,
					     guint                 prop_id,
					     GValue               *value,
					     GParamSpec           *pspec);
static void gtk_toggle_button_update_state  (GtkButton            *button);


static void gtk_toggle_button_activatable_interface_init (GtkActivatableIface  *iface);
static void gtk_toggle_button_update         	     (GtkActivatable       *activatable,
					 	      GtkAction            *action,
						      const gchar          *property_name);
static void gtk_toggle_button_sync_action_properties (GtkActivatable       *activatable,
						      GtkAction            *action);

static GtkActivatableIface *parent_activatable_iface;
static guint                toggle_button_signals[LAST_SIGNAL] = { 0 };

G_DEFINE_TYPE_WITH_CODE (GtkToggleButton, gtk_toggle_button, GTK_TYPE_BUTTON,
			 G_IMPLEMENT_INTERFACE (GTK_TYPE_ACTIVATABLE,
						gtk_toggle_button_activatable_interface_init))

static void
gtk_toggle_button_class_init (GtkToggleButtonClass *class)
{
  GObjectClass *gobject_class;
  GtkWidgetClass *widget_class;
  GtkButtonClass *button_class;

  gobject_class = G_OBJECT_CLASS (class);
  widget_class = (GtkWidgetClass*) class;
  button_class = (GtkButtonClass*) class;

  gobject_class->set_property = gtk_toggle_button_set_property;
  gobject_class->get_property = gtk_toggle_button_get_property;

  widget_class->mnemonic_activate = gtk_toggle_button_mnemonic_activate;

  button_class->pressed = gtk_toggle_button_pressed;
  button_class->released = gtk_toggle_button_released;
  button_class->clicked = gtk_toggle_button_clicked;
  button_class->enter = gtk_toggle_button_update_state;
  button_class->leave = gtk_toggle_button_update_state;

  class->toggled = NULL;

  g_object_class_install_property (gobject_class,
                                   PROP_ACTIVE,
                                   g_param_spec_boolean ("active",
							 P_("Active"),
							 P_("If the toggle button should be pressed in"),
							 FALSE,
							 GTK_PARAM_READWRITE));

  g_object_class_install_property (gobject_class,
                                   PROP_INCONSISTENT,
                                   g_param_spec_boolean ("inconsistent",
							 P_("Inconsistent"),
							 P_("If the toggle button is in an \"in between\" state"),
							 FALSE,
							 GTK_PARAM_READWRITE));

  g_object_class_install_property (gobject_class,
                                   PROP_DRAW_INDICATOR,
                                   g_param_spec_boolean ("draw-indicator",
							 P_("Draw Indicator"),
							 P_("If the toggle part of the button is displayed"),
							 FALSE,
							 GTK_PARAM_READWRITE));

  /**
   * GtkToggleButton::toggled:
   * @togglebutton: the object which received the signal.
   *
   * Should be connected if you wish to perform an action whenever the
   * #GtkToggleButton's state is changed.
   */
  toggle_button_signals[TOGGLED] =
    g_signal_new (I_("toggled"),
		  G_OBJECT_CLASS_TYPE (gobject_class),
		  G_SIGNAL_RUN_FIRST,
		  G_STRUCT_OFFSET (GtkToggleButtonClass, toggled),
		  NULL, NULL,
		  _gtk_marshal_VOID__VOID,
		  G_TYPE_NONE, 0);

  g_type_class_add_private (class, sizeof (GtkToggleButtonPrivate));

  gtk_widget_class_set_accessible_type (widget_class, GTK_TYPE_TOGGLE_BUTTON_ACCESSIBLE);
}

static void
gtk_toggle_button_init (GtkToggleButton *toggle_button)
{
  GtkToggleButtonPrivate *priv;

  toggle_button->priv = G_TYPE_INSTANCE_GET_PRIVATE (toggle_button,
                                                     GTK_TYPE_TOGGLE_BUTTON,
                                                     GtkToggleButtonPrivate);
  priv = toggle_button->priv;

  priv->active = FALSE;
  priv->draw_indicator = FALSE;
  GTK_BUTTON (toggle_button)->priv->depress_on_activate = TRUE;
}

static void
gtk_toggle_button_activatable_interface_init (GtkActivatableIface *iface)
{
  parent_activatable_iface = g_type_interface_peek_parent (iface);
  iface->update = gtk_toggle_button_update;
  iface->sync_action_properties = gtk_toggle_button_sync_action_properties;
}

static void
gtk_toggle_button_update (GtkActivatable *activatable,
			  GtkAction      *action,
			  const gchar    *property_name)
{
  GtkToggleButton *button;

  parent_activatable_iface->update (activatable, action, property_name);

  button = GTK_TOGGLE_BUTTON (activatable);

  if (strcmp (property_name, "active") == 0)
    {
      gtk_action_block_activate (action);
      gtk_toggle_button_set_active (button, gtk_toggle_action_get_active (GTK_TOGGLE_ACTION (action)));
      gtk_action_unblock_activate (action);
    }

}

static void
gtk_toggle_button_sync_action_properties (GtkActivatable *activatable,
				          GtkAction      *action)
{
  GtkToggleButton *button;

  parent_activatable_iface->sync_action_properties (activatable, action);

  if (!GTK_IS_TOGGLE_ACTION (action))
    return;

  button = GTK_TOGGLE_BUTTON (activatable);

  gtk_action_block_activate (action);
  gtk_toggle_button_set_active (button, gtk_toggle_action_get_active (GTK_TOGGLE_ACTION (action)));
  gtk_action_unblock_activate (action);
}

/**
 * gtk_toggle_button_new:
 *
 * Creates a new toggle button. A widget should be packed into the button, as in gtk_button_new().
 *
 * Returns: a new toggle button.
 */
GtkWidget*
gtk_toggle_button_new (void)
{
  return g_object_new (GTK_TYPE_TOGGLE_BUTTON, NULL);
}

/**
 * gtk_toggle_button_new_with_label:
 * @label: a string containing the message to be placed in the toggle button.
 *
 * Creates a new toggle button with a text label.
 *
 * Returns: a new toggle button.
 */
GtkWidget*
gtk_toggle_button_new_with_label (const gchar *label)
{
  return g_object_new (GTK_TYPE_TOGGLE_BUTTON, "label", label, NULL);
}

/**
 * gtk_toggle_button_new_with_mnemonic:
 * @label: the text of the button, with an underscore in front of the
 *         mnemonic character
 *
 * Creates a new #GtkToggleButton containing a label. The label
 * will be created using gtk_label_new_with_mnemonic(), so underscores
 * in @label indicate the mnemonic for the button.
 *
 * Returns: a new #GtkToggleButton
 */
GtkWidget*
gtk_toggle_button_new_with_mnemonic (const gchar *label)
{
  return g_object_new (GTK_TYPE_TOGGLE_BUTTON, 
		       "label", label, 
		       "use-underline", TRUE, 
		       NULL);
}

static void
gtk_toggle_button_set_property (GObject      *object,
				guint         prop_id,
				const GValue *value,
				GParamSpec   *pspec)
{
  GtkToggleButton *tb;

  tb = GTK_TOGGLE_BUTTON (object);

  switch (prop_id)
    {
    case PROP_ACTIVE:
      gtk_toggle_button_set_active (tb, g_value_get_boolean (value));
      break;
    case PROP_INCONSISTENT:
      gtk_toggle_button_set_inconsistent (tb, g_value_get_boolean (value));
      break;
    case PROP_DRAW_INDICATOR:
      gtk_toggle_button_set_mode (tb, g_value_get_boolean (value));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

static void
gtk_toggle_button_get_property (GObject      *object,
				guint         prop_id,
				GValue       *value,
				GParamSpec   *pspec)
{
  GtkToggleButton *tb = GTK_TOGGLE_BUTTON (object);
  GtkToggleButtonPrivate *priv = tb->priv;

  switch (prop_id)
    {
    case PROP_ACTIVE:
      g_value_set_boolean (value, priv->active);
      break;
    case PROP_INCONSISTENT:
      g_value_set_boolean (value, priv->inconsistent);
      break;
    case PROP_DRAW_INDICATOR:
      g_value_set_boolean (value, priv->draw_indicator);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

/**
 * gtk_toggle_button_set_mode:
 * @toggle_button: a #GtkToggleButton
 * @draw_indicator: if %TRUE, draw the button as a separate indicator
 * and label; if %FALSE, draw the button like a normal button
 *
 * Sets whether the button is displayed as a separate indicator and label.
 * You can call this function on a checkbutton or a radiobutton with
 * @draw_indicator = %FALSE to make the button look like a normal button
 *
 * This function only affects instances of classes like #GtkCheckButton
 * and #GtkRadioButton that derive from #GtkToggleButton,
 * not instances of #GtkToggleButton itself.
 */
void
gtk_toggle_button_set_mode (GtkToggleButton *toggle_button,
			    gboolean         draw_indicator)
{
  GtkToggleButtonPrivate *priv;

  g_return_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button));

  priv = toggle_button->priv;

  draw_indicator = draw_indicator ? TRUE : FALSE;

  if (priv->draw_indicator != draw_indicator)
    {
      GtkStyleContext *context;

      priv->draw_indicator = draw_indicator;
      GTK_BUTTON (toggle_button)->priv->depress_on_activate = !draw_indicator;

      if (gtk_widget_get_visible (GTK_WIDGET (toggle_button)))
	gtk_widget_queue_resize (GTK_WIDGET (toggle_button));

      g_object_notify (G_OBJECT (toggle_button), "draw-indicator");

      /* Make toggle buttons conditionally have the "button"
       * class depending on draw_indicator.
       */
      context = gtk_widget_get_style_context (GTK_WIDGET (toggle_button));

      if (draw_indicator)
        gtk_style_context_remove_class (context, GTK_STYLE_CLASS_BUTTON);
      else
        gtk_style_context_add_class (context, GTK_STYLE_CLASS_BUTTON);
    }
}

/**
 * gtk_toggle_button_get_mode:
 * @toggle_button: a #GtkToggleButton
 *
 * Retrieves whether the button is displayed as a separate indicator
 * and label. See gtk_toggle_button_set_mode().
 *
 * Return value: %TRUE if the togglebutton is drawn as a separate indicator
 *   and label.
 **/
gboolean
gtk_toggle_button_get_mode (GtkToggleButton *toggle_button)
{
  g_return_val_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button), FALSE);

  return toggle_button->priv->draw_indicator;
}

/**
 * gtk_toggle_button_set_active:
 * @toggle_button: a #GtkToggleButton.
 * @is_active: %TRUE or %FALSE.
 *
 * Sets the status of the toggle button. Set to %TRUE if you want the
 * GtkToggleButton to be 'pressed in', and %FALSE to raise it.
 * This action causes the toggled signal to be emitted.
 */
void
gtk_toggle_button_set_active (GtkToggleButton *toggle_button,
			      gboolean         is_active)
{
  GtkToggleButtonPrivate *priv;

  g_return_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button));

  priv = toggle_button->priv;

  is_active = is_active != FALSE;

  if (priv->active != is_active)
    gtk_button_clicked (GTK_BUTTON (toggle_button));
}

void
_gtk_toggle_button_set_active (GtkToggleButton *toggle_button,
                               gboolean         is_active)
{
  toggle_button->priv->active = is_active;
}

/**
 * gtk_toggle_button_get_active:
 * @toggle_button: a #GtkToggleButton.
 *
 * Queries a #GtkToggleButton and returns its current state. Returns %TRUE if
 * the toggle button is pressed in and %FALSE if it is raised.
 *
 * Returns: a #gboolean value.
 */
gboolean
gtk_toggle_button_get_active (GtkToggleButton *toggle_button)
{
  g_return_val_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button), FALSE);

  return toggle_button->priv->active;
}

/**
 * gtk_toggle_button_toggled:
 * @toggle_button: a #GtkToggleButton.
 *
 * Emits the #GtkToggleButton::toggled signal on the
 * #GtkToggleButton. There is no good reason for an
 * application ever to call this function.
 */
void
gtk_toggle_button_toggled (GtkToggleButton *toggle_button)
{
  g_return_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button));

  g_signal_emit (toggle_button, toggle_button_signals[TOGGLED], 0);
}

/**
 * gtk_toggle_button_set_inconsistent:
 * @toggle_button: a #GtkToggleButton
 * @setting: %TRUE if state is inconsistent
 *
 * If the user has selected a range of elements (such as some text or
 * spreadsheet cells) that are affected by a toggle button, and the
 * current values in that range are inconsistent, you may want to
 * display the toggle in an "in between" state. This function turns on
 * "in between" display.  Normally you would turn off the inconsistent
 * state again if the user toggles the toggle button. This has to be
 * done manually, gtk_toggle_button_set_inconsistent() only affects
 * visual appearance, it doesn't affect the semantics of the button.
 * 
 **/
void
gtk_toggle_button_set_inconsistent (GtkToggleButton *toggle_button,
                                    gboolean         setting)
{
  GtkToggleButtonPrivate *priv;

  g_return_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button));

  priv = toggle_button->priv;

  setting = setting != FALSE;

  if (setting != priv->inconsistent)
    {
      priv->inconsistent = setting;

      gtk_toggle_button_update_state (GTK_BUTTON (toggle_button));
      gtk_widget_queue_draw (GTK_WIDGET (toggle_button));

      g_object_notify (G_OBJECT (toggle_button), "inconsistent");      
    }
}

/**
 * gtk_toggle_button_get_inconsistent:
 * @toggle_button: a #GtkToggleButton
 * 
 * Gets the value set by gtk_toggle_button_set_inconsistent().
 * 
 * Return value: %TRUE if the button is displayed as inconsistent, %FALSE otherwise
 **/
gboolean
gtk_toggle_button_get_inconsistent (GtkToggleButton *toggle_button)
{
  g_return_val_if_fail (GTK_IS_TOGGLE_BUTTON (toggle_button), FALSE);

  return toggle_button->priv->inconsistent;
}

static gboolean
gtk_toggle_button_mnemonic_activate (GtkWidget *widget,
                                     gboolean   group_cycling)
{
  /*
   * We override the standard implementation in 
   * gtk_widget_real_mnemonic_activate() in order to focus the widget even
   * if there is no mnemonic conflict.
   */
  if (gtk_widget_get_can_focus (widget))
    gtk_widget_grab_focus (widget);

  if (!group_cycling)
    gtk_widget_activate (widget);

  return TRUE;
}

static void
gtk_toggle_button_pressed (GtkButton *button)
{
  button->priv->button_down = TRUE;

  gtk_toggle_button_update_state (button);
  gtk_widget_queue_draw (GTK_WIDGET (button));
}

static void
gtk_toggle_button_released (GtkButton *button)
{
  if (button->priv->button_down)
    {
      button->priv->button_down = FALSE;

      if (button->priv->in_button)
	gtk_button_clicked (button);

      gtk_toggle_button_update_state (button);
      gtk_widget_queue_draw (GTK_WIDGET (button));
    }
}

static void
gtk_toggle_button_clicked (GtkButton *button)
{
  GtkToggleButton *toggle_button = GTK_TOGGLE_BUTTON (button);
  GtkToggleButtonPrivate *priv = toggle_button->priv;

  priv->active = !priv->active;

  gtk_toggle_button_toggled (toggle_button);

  gtk_toggle_button_update_state (button);

  g_object_notify (G_OBJECT (toggle_button), "active");

  if (GTK_BUTTON_CLASS (gtk_toggle_button_parent_class)->clicked)
    GTK_BUTTON_CLASS (gtk_toggle_button_parent_class)->clicked (button);
}

static void
gtk_toggle_button_update_state (GtkButton *button)
{
  GtkToggleButton *toggle_button = GTK_TOGGLE_BUTTON (button);
  GtkToggleButtonPrivate *priv = toggle_button->priv;
  gboolean depressed;
  GtkStateFlags new_state = 0;

  new_state = gtk_widget_get_state_flags (GTK_WIDGET (button)) &
    ~(GTK_STATE_FLAG_INCONSISTENT |
      GTK_STATE_FLAG_PRELIGHT |
      GTK_STATE_FLAG_ACTIVE);

  if (priv->inconsistent)
    new_state |= GTK_STATE_FLAG_INCONSISTENT;

  if (priv->inconsistent)
    depressed = FALSE;
  else if (button->priv->in_button && button->priv->button_down)
    depressed = TRUE;
  else
    depressed = priv->active;

  if (button->priv->in_button && (!button->priv->button_down || priv->draw_indicator))
    new_state |= GTK_STATE_FLAG_PRELIGHT;

  if (depressed)
    new_state |= GTK_STATE_FLAG_ACTIVE;

  _gtk_button_set_depressed (button, depressed);
  gtk_widget_set_state_flags (GTK_WIDGET (toggle_button), new_state, TRUE);
}