path: root/e-util/e-dialog-widgets.c

/* Evolution internal utilities - Glade dialog widget utilities
 *
 * Copyright (C) 2000 Ximian, Inc.
 * Copyright (C) 2000 Ximian, Inc.
 *
 * Author: Federico Mena-Quintero <federico@ximian.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */

#include <config.h>

#include <math.h>
#include <string.h>
#include <time.h>
#include <gtk/gtkmenu.h>
#include <gtk/gtkmenuitem.h>
#include <gtk/gtkoptionmenu.h>
#include <gtk/gtkradiobutton.h>
#include <gtk/gtksignal.h>
#include <gtk/gtkspinbutton.h>
#include <libgnomeui/gnome-dateedit.h>
#include <libgnomeui/gnome-propertybox.h>
#include <gal/widgets/e-unicode.h>

#include "e-dialog-widgets.h"



/* A widget, a pointer to the variable it will modify, and extra information */
typedef struct {
    GtkWidget *widget;
    gpointer value_var;
    gpointer info;
} WidgetHook;

/* Hook information for a complete dialog */
typedef struct {
    GSList *whooks;
} DialogHooks;



/* Destroy handler for the dialog; frees the dialog hooks */
static void
dialog_destroy_cb (GtkObject *dialog, gpointer data)
{
    DialogHooks *hooks;

    hooks = data;

    g_slist_free (hooks->whooks);
    hooks->whooks = NULL;

    g_free (hooks);
    gtk_object_set_data (dialog, "dialog-hooks", NULL);
}

/* Ensures that the dialog has the necessary attached data to store the widget
 * hook information.
 */
static DialogHooks *
get_dialog_hooks (GtkWidget *dialog)
{
    DialogHooks *hooks;

    hooks = gtk_object_get_data (GTK_OBJECT (dialog), "dialog-hooks");
    if (!hooks) {
        hooks = g_new0 (DialogHooks, 1);
        gtk_object_set_data (GTK_OBJECT (dialog), "dialog-hooks", hooks);
        gtk_signal_connect (GTK_OBJECT (dialog), "destroy",
                    GTK_SIGNAL_FUNC (dialog_destroy_cb), hooks);
    }

    return hooks;
}

/* Converts an mapped value to the appropriate index in an item group.  The
 * values for the items are provided as a -1-terminated array.
 */
static int
value_to_index (const int *value_map, int value)
{
    int i;

    for (i = 0; value_map[i] != -1; i++)
        if (value_map[i] == value)
            return i;

    return -1;
}

/* Converts an index in an item group to the appropriate mapped value.  See the
 * function above.
 */
static int
index_to_value (const int *value_map, int index)
{
    int i;

    /* We do this the hard way, i.e. not as a simple array reference, to
     * check for correctness.
     */

    for (i = 0; value_map[i] != -1; i++)
        if (i == index)
            return value_map[i];

    return -1;
}

/* Callback for the "toggled" signal of toggle buttons */
static void
toggled_cb (GtkToggleButton *toggle, gpointer data)
{
    GnomePropertyBox *pbox;

    pbox = GNOME_PROPERTY_BOX (data);

    /* For radio buttons, we only notify the property box if the button is
     * active, because we'll get one call for each of the changed buttons in
     * the radio group.
     */
    if (!GTK_IS_RADIO_BUTTON (toggle) || toggle->active)
        gnome_property_box_changed (pbox);
}

/* Hooks a radio button group */
static void
hook_radio (GtkWidget *dialog, GtkRadioButton *radio, gpointer value_var, gpointer info)
{
    GSList *group;
    GSList *l;
    int *value;
    const int *value_map;

    group = gtk_radio_button_group (radio);

    /* Set the value */

    value = (int *) value_var;
    value_map = (const int *) info;

    e_dialog_radio_set (GTK_WIDGET (radio), *value, value_map);

    /* Hook to changed */

    if (GNOME_IS_PROPERTY_BOX (dialog))
        for (l = group; l; l = l->next)
            gtk_signal_connect (GTK_OBJECT (l->data), "toggled",
                        GTK_SIGNAL_FUNC (toggled_cb), dialog);
}

/* Gets the value of a radio button group */
static void
get_radio_value (GtkRadioButton *radio, gpointer value_var, gpointer info)
{
    int *value;
    const int *value_map;

    value = (int *) value_var;
    value_map = (const int *) info;

    *value = e_dialog_radio_get (GTK_WIDGET (radio), value_map);
}

/* Callback for the "activate" signal of menu items */
static void
activate_cb (GtkMenuItem *item, gpointer data)
{
    GnomePropertyBox *pbox;

    pbox = GNOME_PROPERTY_BOX (data);
    gnome_property_box_changed (pbox);
}

/* Hooks an option menu */
static void
hook_option_menu (GtkWidget *dialog, GtkOptionMenu *omenu, gpointer value_var, gpointer info)
{
    int *value;
    const int *value_map;

    /* Set the value */

    value = (int *) value_var;
    value_map = (const int *) info;

    e_dialog_option_menu_set (GTK_WIDGET (omenu), *value, value_map);

    /* Hook to changed */

    if (GNOME_IS_PROPERTY_BOX (dialog)) {
        GtkMenu *menu;
        GList *l;

        menu = GTK_MENU (gtk_option_menu_get_menu (omenu));

        for (l = GTK_MENU_SHELL (menu)->children; l; l = l->next)
            gtk_signal_connect (GTK_OBJECT (l->data), "activate",
                        GTK_SIGNAL_FUNC (activate_cb), dialog);
    }
}

/* Gets the value of an option menu */
static void
get_option_menu_value (GtkOptionMenu *omenu, gpointer value_var, gpointer info)
{
    int *value;
    const int *value_map;

    value = (int *) value_var;
    value_map = (const int *) info;

    *value = e_dialog_option_menu_get (GTK_WIDGET (omenu), value_map);
}

/* Hooks a toggle button */
static void
hook_toggle (GtkWidget *dialog, GtkToggleButton *toggle, gpointer value_var, gpointer info)
{
    gboolean *value;

    /* Set the value */

    value = (gboolean *) value_var;
    e_dialog_toggle_set (GTK_WIDGET (toggle), *value);

    /* Hook to changed */

    if (GNOME_IS_PROPERTY_BOX (dialog))
        gtk_signal_connect (GTK_OBJECT (toggle), "toggled",
                    GTK_SIGNAL_FUNC (toggled_cb), dialog);
}

/* Gets the value of a toggle button */
static void
get_toggle_value (GtkToggleButton *toggle, gpointer value_var, gpointer info)
{
    gboolean *value;

    value = (gboolean *) value_var;
    *value = e_dialog_toggle_get (GTK_WIDGET (toggle));
}

/* Callback for the "value_changed" signal of the adjustment of a spin button */
static void
value_changed_cb (GtkAdjustment *adj, gpointer data)
{
    GnomePropertyBox *pbox;

    pbox = GNOME_PROPERTY_BOX (data);
    gnome_property_box_changed (pbox);
}

/* Hooks a spin button */
static void
hook_spin_button (GtkWidget *dialog, GtkSpinButton *spin, gpointer value_var, gpointer info)
{
    double *value;
    GtkAdjustment *adj;

    /* Set the value */

    value = (double *) value_var;
    e_dialog_spin_set (GTK_WIDGET (spin), *value);

    /* Hook to changed */

    adj = gtk_spin_button_get_adjustment (spin);

    if (GNOME_IS_PROPERTY_BOX (dialog))
        gtk_signal_connect (GTK_OBJECT (adj), "value_changed",
                    GTK_SIGNAL_FUNC (value_changed_cb), dialog);
}

/* Gets the value of a spin button */
static void
get_spin_button_value (GtkSpinButton *spin, gpointer value_var, gpointer info)
{
    double *value;

    value = (double *) value_var;
    *value = e_dialog_spin_get_double (GTK_WIDGET (spin));
}

/* Callback for the "changed" signal of a GtkEditable widget */
static void
changed_cb (GtkEditable *editable, gpointer data)
{
    GnomePropertyBox *pbox;

    pbox = GNOME_PROPERTY_BOX (data);
    gnome_property_box_changed (pbox);
}

/* Hooks a GtkEditable widget */
static void
hook_editable (GtkWidget *dialog, GtkEditable *editable, gpointer value_var, gpointer info)
{
    char **value;

    /* Set the value */

    value = (char **) value_var;

    e_dialog_editable_set (GTK_WIDGET (editable), *value);

    /* Hook to changed */

    if (GNOME_IS_PROPERTY_BOX (dialog))
        gtk_signal_connect (GTK_OBJECT (editable), "changed",
                    GTK_SIGNAL_FUNC (changed_cb), dialog);
}

/* Gets the value of a GtkEditable widget */
static void
get_editable_value (GtkEditable *editable, gpointer value_var, gpointer data)
{
    char **value;

    value = (char **) value_var;
    if (*value)
        g_free (*value);

    *value = e_dialog_editable_get (GTK_WIDGET (editable));
}

/**
 * e_dialog_editable_set:
 * @widget: A #GtkEditable widget.
 * @value: String value.
 * 
 * Sets the string value inside a #GtkEditable-derived widget.
 **/
void
e_dialog_editable_set (GtkWidget *widget, const char *value)
{
    g_return_if_fail (widget != NULL);
    g_return_if_fail (GTK_IS_EDITABLE (widget));

    gtk_editable_delete_text (GTK_EDITABLE (widget), 0, -1);

    if (value) {
        gint pos;

        pos = 0;
        e_utf8_gtk_editable_insert_text (GTK_EDITABLE (widget), value, strlen (value), &pos);
    }
}

/**
 * e_dialog_editable_get:
 * @widget: A #GtkEditable widget.
 * 
 * Queries the string value inside a #GtkEditable-derived widget.
 * 
 * Return value: String value.  You should free it when you are done with it.
 * This function can return NULL if the string could not be converted from
 * GTK+'s encoding into UTF8.
 **/
char *
e_dialog_editable_get (GtkWidget *widget)
{
    g_return_val_if_fail (widget != NULL, NULL);
    g_return_val_if_fail (GTK_IS_EDITABLE (widget), NULL);

    return e_utf8_gtk_editable_get_chars (GTK_EDITABLE (widget), 0, -1);
}

/**
 * e_dialog_radio_set:
 * @widget: A #GtkRadioButton in a radio button group.
 * @value: Enumerated value.
 * @value_map: Map from enumeration values to array indices.
 * 
 * Sets the selected item in a radio group.  The specified @widget can be any of
 * the #GtkRadioButtons in the group.  Each radio button should correspond to an
 * enumeration value; the specified @value will be mapped to an integer from
 * zero to the number of items in the group minus 1 by using a mapping table
 * specified in @value_map.  The last element in this table should be -1.  Thus
 * a table to map three possible interpolation values to integers could be
 * specified as { NEAREST_NEIGHBOR, BILINEAR, HYPERBOLIC, -1 }.
 **/
void
e_dialog_radio_set (GtkWidget *widget, int value, const int *value_map)
{
    GSList *group;
    int i;
    GSList *l;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (GTK_IS_RADIO_BUTTON (widget));
    g_return_if_fail (value_map != NULL);

    group = gtk_radio_button_group (GTK_RADIO_BUTTON (widget));

    i = value_to_index (value_map, value);
    if (i != -1) {
        /* Groups are built by prepending items, so the list ends up in reverse
         * order; we need to flip the index around.
         */
        i = g_slist_length (group) - i - 1;

        l = g_slist_nth (group, i);
        if (!l)
            g_message ("e_dialog_radio_set(): could not find index %d in radio group!",
                   i);

        gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (l->data), TRUE);
    } else
        g_message ("e_dialog_radio_set(): could not find value %d in value map!",
               value);
}

/**
 * e_dialog_radio_get:
 * @widget: A #GtkRadioButton in a radio button group.
 * @value_map: Map from enumeration values to array indices.
 * 
 * Queries the selected item in a #GtkRadioButton group.  Please read the
 * description of e_dialog_radio_set() to see how @value_map maps enumeration
 * values to button indices.
 * 
 * Return value: Enumeration value which corresponds to the selected item in the
 * radio group.
 **/
int
e_dialog_radio_get (GtkWidget *widget, const int *value_map)
{
    GSList *group;
    GSList *l;
    int i;
    int v;

    g_return_val_if_fail (widget != NULL, -1);
    g_return_val_if_fail (GTK_IS_RADIO_BUTTON (widget), -1);
    g_return_val_if_fail (value_map != NULL, -1);

    group = gtk_radio_button_group (GTK_RADIO_BUTTON (widget));

    for (i = 0, l = group; l; l = l->next, i++) {
        widget = GTK_WIDGET (l->data);

        if (GTK_TOGGLE_BUTTON (widget)->active)
            break;
    }

    if (!l)
        g_assert_not_reached ();

    /* Groups are built by prepending items, so the list ends up in reverse
     * order; we need to flip the index around.
     */
    i = g_slist_length (group) - i - 1;

    v = index_to_value (value_map, i);
    if (v == -1) {
        g_message ("e_dialog_radio_get(): could not find index %d in value map!", i);
        return -1;
    }

    return v;
}

/**
 * e_dialog_toggle_set:
 * @widget: A #GtkToggleButton.
 * @value: Toggle value.
 * 
 * Sets the value of a #GtkToggleButton-derived widget.  This should not be used
 * for radio buttons; it is more convenient to use use e_dialog_radio_set()
 * instead.
 **/
void
e_dialog_toggle_set (GtkWidget *widget, gboolean value)
{
    g_return_if_fail (widget != NULL);
    g_return_if_fail (GTK_IS_TOGGLE_BUTTON (widget));

    gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (widget), value);
}

/**
 * e_dialog_toggle_get:
 * @widget: A #GtkToggleButton.
 * 
 * Queries the value of a #GtkToggleButton-derived widget.  This should not be
 * used for radio buttons; it is more convenient to use e_dialog_radio_get()
 * instead.
 * 
 * Return value: Toggle value.
 **/
gboolean
e_dialog_toggle_get (GtkWidget *widget)
{
    g_return_val_if_fail (widget != NULL, FALSE);
    g_return_val_if_fail (GTK_IS_TOGGLE_BUTTON (widget), FALSE);

    return GTK_TOGGLE_BUTTON (widget)->active;
}

/**
 * e_dialog_spin_set:
 * @widget: A #GtkSpinButton.
 * @value: Numeric value.
 * 
 * Sets the value of a #GtkSpinButton widget.
 **/
void
e_dialog_spin_set (GtkWidget *widget, double value)
{
    GtkAdjustment *adj;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (GTK_IS_SPIN_BUTTON (widget));

    adj = gtk_spin_button_get_adjustment (GTK_SPIN_BUTTON (widget));

    adj->value = value;
    gtk_signal_emit_by_name (GTK_OBJECT (adj), "value_changed");
}

/**
 * e_dialog_spin_get_double:
 * @widget: A #GtkSpinButton.
 * 
 * Queries the floating-point value of a #GtkSpinButton widget.
 * 
 * Return value: Numeric value.
 **/
double
e_dialog_spin_get_double (GtkWidget *widget)
{
    GtkAdjustment *adj;

    g_return_val_if_fail (widget != NULL, 0.0);
    g_return_val_if_fail (GTK_IS_SPIN_BUTTON (widget), 0.0);

    adj = gtk_spin_button_get_adjustment (GTK_SPIN_BUTTON (widget));
    return adj->value;
}

/**
 * e_dialog_spin_get_int:
 * @widget: A #GtkSpinButton.
 * 
 * Queries the integer value of a #GtkSpinButton widget.
 * 
 * Return value: Numeric value.
 **/
int
e_dialog_spin_get_int (GtkWidget *widget)
{
    double value;

    g_return_val_if_fail (widget != NULL, -1);
    g_return_val_if_fail (GTK_IS_SPIN_BUTTON (widget), -1);

    value = e_dialog_spin_get_double (widget);
    return (int) floor (value);
}

/**
 * e_dialog_option_menu_set:
 * @widget: A #GtkOptionMenu.
 * @value: Enumerated value.
 * @value_map: Map from enumeration values to array indices.
 * 
 * Sets the selected item in a #GtkOptionMenu.  Please read the description of
 * e_dialog_radio_set() to see how @value_map maps enumeration values to item
 * indices.
 **/
void
e_dialog_option_menu_set (GtkWidget *widget, int value, const int *value_map)
{
    int i;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (GTK_IS_OPTION_MENU (widget));
    g_return_if_fail (value_map != NULL);

    i = value_to_index (value_map, value);

    if (i != -1)
        gtk_option_menu_set_history (GTK_OPTION_MENU (widget), i);
    else
        g_message ("e_dialog_option_menu_set(): could not find value %d in value map!",
               value);
}

/**
 * e_dialog_option_menu_get:
 * @widget: A #GtkOptionMenu.
 * @value_map: Map from enumeration values to array indices.
 * 
 * Queries the selected item in a #GtkOptionMenu.  Please read the description
 * of e_dialog_radio_set() to see how @value_map maps enumeration values to item
 * indices.
 * 
 * Return value: Enumeration value which corresponds to the selected item in the
 * option menu.
 **/
int
e_dialog_option_menu_get (GtkWidget *widget, const int *value_map)
{
    GtkMenu *menu;
    GtkWidget *active;
    GList *children;
    GList *l;
    int i;
    int v;

    g_return_val_if_fail (widget != NULL, -1);
    g_return_val_if_fail (GTK_IS_OPTION_MENU (widget), -1);
    g_return_val_if_fail (value_map != NULL, -1);

    menu = GTK_MENU (gtk_option_menu_get_menu (GTK_OPTION_MENU (widget)));

    active = gtk_menu_get_active (menu);
    g_assert (active != NULL);

    children = GTK_MENU_SHELL (menu)->children;

    for (i = 0, l = children; l; l = l->next, i++) {
        if (GTK_WIDGET (l->data) == active)
            break;
    }

    if (!l)
        g_assert_not_reached ();

    v = index_to_value (value_map, i);
    if (v == -1) {
        g_message ("e_dialog_option_menu_get(): could not find index %d in value map!", i);
        return -1;
    }

    return v;
}

/**
 * e_dialog_dateedit_set:
 * @widget: A #GnomeDateEdit widget.
 * @t: Date/time value.
 * 
 * Sets the value of a #GnomeDateEdit widget.
 **/
void
e_dialog_dateedit_set (GtkWidget *widget, time_t t)
{
    g_return_if_fail (widget != NULL);
    g_return_if_fail (GNOME_IS_DATE_EDIT (widget));

    gnome_date_edit_set_time (GNOME_DATE_EDIT (widget), t);
}

/**
 * e_dialog_dateedit_get:
 * @widget: A #GnomeDateEdit widget.
 * 
 * Queries the value of a #GnomeDateEdit widget.
 * 
 * Return value: Date/time value.
 **/
time_t
e_dialog_dateedit_get (GtkWidget *widget)
{
    g_return_val_if_fail (widget != NULL, -1);
    g_return_val_if_fail (GNOME_IS_DATE_EDIT (widget), -1);

    return gnome_date_edit_get_date (GNOME_DATE_EDIT (widget));
}

/**
 * e_dialog_widget_hook_value:
 * @dialog: Dialog box in which the @widget lives in.
 * @widget: A widget that will control a variable.
 * @value_var: Pointer to the variable that the @widget will control.
 * @info: NULL for most widgets, or an integer value map array (see
 * e_dialog_radio_set() for details).
 * 
 * Hooks a widget from a dialog box to the variable it will modify.  Supported
 * widgets are:  #GtkEditable (char *), #GtkRadioButton (int/value_map pair; see
 * e_dialog_radio_set() for more information), #GtkTogglebutton (gboolean),
 * #GtkSpinButton (double), #GtkOptionMenu (int/value_map pair), and
 * #GnomeDateEdit (time_t).
 *
 * A pointer to the appropriate variable to modify should be passed in @value_var.
 * For values that take a value_map array as well, it should be passed in @info.
 *
 * The widgets within a dialog that are hooked with this function will set their
 * respective variables only when e_dialog_get_values() is called.  The typical
 * use is to call that function in the handler for the "OK" button of a dialog
 * box.
 *
 * In addition, if the specified @dialog is a #GnomePropertyBox, the widgets wil
 * automatically turn on the "Apply" button of the property box when they are
 * modified by the user.
 * 
 * Return value: TRUE if the type of the specified @widget is supported, FALSE
 * otherwise.
 **/
gboolean
e_dialog_widget_hook_value (GtkWidget *dialog, GtkWidget *widget,
                gpointer value_var, gpointer info)
{
    DialogHooks *hooks;
    WidgetHook *wh;

    g_return_val_if_fail (dialog != NULL, FALSE);
    g_return_val_if_fail (widget != NULL, FALSE);
    g_return_val_if_fail (GTK_IS_WIDGET (widget), FALSE);
    g_return_val_if_fail (value_var != NULL, FALSE);

    hooks = get_dialog_hooks (dialog);

    /* First check if it is a "group" widget, like a radio button or an
     * option menu.  Then we check for normal ungrouped widgets.
     */

    if (GTK_IS_RADIO_BUTTON (widget))
        hook_radio (dialog, GTK_RADIO_BUTTON (widget), value_var, info);
    else if (GTK_IS_OPTION_MENU (widget))
        hook_option_menu (dialog, GTK_OPTION_MENU (widget), value_var, info);
    else if (GTK_IS_TOGGLE_BUTTON (widget))
        hook_toggle (dialog, GTK_TOGGLE_BUTTON (widget), value_var, info);
    else if (GTK_IS_SPIN_BUTTON (widget))
        hook_spin_button (dialog, GTK_SPIN_BUTTON (widget), value_var, info);
    else if (GTK_IS_EDITABLE (widget))
        hook_editable (dialog, GTK_EDITABLE (widget), value_var, info);
    else
        return FALSE;

    wh = g_new (WidgetHook, 1);
    wh->widget = widget;
    wh->value_var = value_var;
    wh->info = info;

    hooks->whooks = g_slist_prepend (hooks->whooks, wh);

    return TRUE;
}

/**
 * e_dialog_get_values:
 * @dialog: A dialog box whose widgets have been hooked to the appropriate
 * variables with e_dialog_widget_hook_value().
 * 
 * Makes every widget in a @dialog that was hooked with
 * e_dialog_widget_hook_value() apply its value to its corresponding variable.
 * The typical usage is to call this function in the handler for the "OK" button
 * of a dialog box.
 **/
void
e_dialog_get_values (GtkWidget *dialog)
{
    DialogHooks *hooks;
    GSList *l;

    g_return_if_fail (dialog != NULL);

    hooks = get_dialog_hooks (dialog);

    for (l = hooks->whooks; l; l = l->next) {
        WidgetHook *wh;

        wh = l->data;

        if (GTK_IS_RADIO_BUTTON (wh->widget))
            get_radio_value (GTK_RADIO_BUTTON (wh->widget), wh->value_var, wh->info);
        else if (GTK_IS_OPTION_MENU (wh->widget))
            get_option_menu_value (GTK_OPTION_MENU (wh->widget), wh->value_var, wh->info);
        else if (GTK_IS_TOGGLE_BUTTON (wh->widget))
            get_toggle_value (GTK_TOGGLE_BUTTON (wh->widget), wh->value_var, wh->info);
        else if (GTK_IS_SPIN_BUTTON (wh->widget))
            get_spin_button_value (GTK_SPIN_BUTTON (wh->widget), wh->value_var, wh->info);
        else if (GTK_IS_EDITABLE (wh->widget))
            get_editable_value (GTK_EDITABLE (wh->widget), wh->value_var, wh->info);
        else
            g_assert_not_reached ();
    }
}

/**
 * e_dialog_xml_widget_hook_value:
 * @xml: Glade XML description of a dialog box.
 * @dialog: Dialog box in which the widget lives in.
 * @widget_name: Name of the widget in the Glade XML data.
 * @value_var: Pointer to the variable that the widget will control.
 * @info: NULL for most widgets, or an integer value map array (see
 * e_dialog_radio_set() for details).
 * 
 * Similar to e_dialog_widget_hook_value(), but uses the widget from a #GladeXML
 * data structure.
 * 
 * Return value: TRUE if the type of the specified widget is supported, FALSE
 * otherwise.
 **/
gboolean
e_dialog_xml_widget_hook_value (GladeXML *xml, GtkWidget *dialog, const char *widget_name,
                gpointer value_var, gpointer info)
{
    GtkWidget *widget;

    g_return_val_if_fail (xml != NULL, FALSE);
    g_return_val_if_fail (GLADE_IS_XML (xml), FALSE);
    g_return_val_if_fail (dialog != NULL, FALSE);
    g_return_val_if_fail (widget_name != NULL, FALSE);
    g_return_val_if_fail (value_var != NULL, FALSE);

    widget = glade_xml_get_widget (xml, widget_name);
    if (!widget) {
        g_message ("e_dialog_xml_widget_hook_value(): could not find widget `%s' in "
               "Glade data!", widget_name);
        return FALSE;
    }

    return e_dialog_widget_hook_value (dialog, widget, value_var, info);
}