gtk2/gtk/gtkappchooserbutton.c
2011-04-12 12:24:05 -04:00

872 lines
25 KiB
C

/*
* gtkappchooserbutton.h: an app-chooser combobox
*
* Copyright (C) 2010 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with the Gnome Library; see the file COPYING.LIB. If not,
* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Authors: Cosimo Cecchi <ccecchi@redhat.com>
*/
/**
* SECTION:gtkappchooserbutton
* @Title: GtkAppChooserButton
* @Short_description: A button to launch an application chooser dialog
*
* The #GtkAppChooserButton is a widget that lets the user select
* an application. It implements the #GtkAppChooser interface.
*/
#include "config.h"
#include "gtkappchooserbutton.h"
#include "gtkappchooser.h"
#include "gtkappchooserdialog.h"
#include "gtkappchooserprivate.h"
#include "gtkcelllayout.h"
#include "gtkcellrendererpixbuf.h"
#include "gtkcellrenderertext.h"
#include "gtkcombobox.h"
#include "gtkdialog.h"
#include "gtkintl.h"
#include "gtkmarshalers.h"
enum {
PROP_CONTENT_TYPE = 1,
PROP_SHOW_DIALOG_ITEM,
PROP_HEADING
};
enum {
SIGNAL_CUSTOM_ITEM_ACTIVATED,
NUM_SIGNALS
};
enum {
COLUMN_APP_INFO,
COLUMN_NAME,
COLUMN_LABEL,
COLUMN_ICON,
COLUMN_CUSTOM,
COLUMN_SEPARATOR,
NUM_COLUMNS,
};
#define CUSTOM_ITEM_OTHER_APP "gtk-internal-item-other-app"
static void app_chooser_iface_init (GtkAppChooserIface *iface);
static void real_insert_custom_item (GtkAppChooserButton *self,
const gchar *name,
const gchar *label,
GIcon *icon,
gboolean custom,
GtkTreeIter *iter);
static void real_insert_separator (GtkAppChooserButton *self,
gboolean custom,
GtkTreeIter *iter);
static guint signals[NUM_SIGNALS] = { 0, };
G_DEFINE_TYPE_WITH_CODE (GtkAppChooserButton, gtk_app_chooser_button, GTK_TYPE_COMBO_BOX,
G_IMPLEMENT_INTERFACE (GTK_TYPE_APP_CHOOSER,
app_chooser_iface_init));
struct _GtkAppChooserButtonPrivate {
GtkListStore *store;
gchar *content_type;
gchar *heading;
gint last_active;
gboolean show_dialog_item;
GHashTable *custom_item_names;
};
static gboolean
row_separator_func (GtkTreeModel *model,
GtkTreeIter *iter,
gpointer user_data)
{
gboolean separator;
gtk_tree_model_get (model, iter,
COLUMN_SEPARATOR, &separator,
-1);
return separator;
}
static void
get_first_iter (GtkListStore *store,
GtkTreeIter *iter)
{
GtkTreeIter iter2;
if (!gtk_tree_model_get_iter_first (GTK_TREE_MODEL (store), iter))
{
/* the model is empty, append */
gtk_list_store_append (store, iter);
}
else
{
gtk_list_store_insert_before (store, &iter2, iter);
*iter = iter2;
}
}
typedef struct {
GtkAppChooserButton *self;
GAppInfo *info;
gint active_index;
} SelectAppData;
static void
select_app_data_free (SelectAppData *data)
{
g_clear_object (&data->self);
g_clear_object (&data->info);
g_slice_free (SelectAppData, data);
}
static gboolean
select_application_func_cb (GtkTreeModel *model,
GtkTreePath *path,
GtkTreeIter *iter,
gpointer user_data)
{
SelectAppData *data = user_data;
GAppInfo *app_to_match = data->info, *app = NULL;
gboolean custom;
gboolean result;
gtk_tree_model_get (model, iter,
COLUMN_APP_INFO, &app,
COLUMN_CUSTOM, &custom,
-1);
/* custom items are always after GAppInfos, so iterating further here
* is just useless.
*/
if (custom)
result = TRUE;
else if (g_app_info_equal (app, app_to_match))
{
gtk_combo_box_set_active_iter (GTK_COMBO_BOX (data->self), iter);
result = TRUE;
}
else
result = FALSE;
g_object_unref (app);
return result;
}
static void
gtk_app_chooser_button_select_application (GtkAppChooserButton *self,
GAppInfo *info)
{
SelectAppData *data;
data = g_slice_new0 (SelectAppData);
data->self = g_object_ref (self);
data->info = g_object_ref (info);
gtk_tree_model_foreach (GTK_TREE_MODEL (self->priv->store),
select_application_func_cb, data);
select_app_data_free (data);
}
static void
other_application_dialog_response_cb (GtkDialog *dialog,
gint response_id,
gpointer user_data)
{
GtkAppChooserButton *self = user_data;
GAppInfo *info;
if (response_id != GTK_RESPONSE_OK)
{
/* reset the active item, otherwise we are stuck on
* 'Other application...'
*/
gtk_combo_box_set_active (GTK_COMBO_BOX (self), self->priv->last_active);
gtk_widget_destroy (GTK_WIDGET (dialog));
return;
}
info = gtk_app_chooser_get_app_info (GTK_APP_CHOOSER (dialog));
/* refresh the combobox to get the new application */
gtk_app_chooser_refresh (GTK_APP_CHOOSER (self));
gtk_app_chooser_button_select_application (self, info);
g_object_unref (info);
}
static void
other_application_item_activated_cb (GtkAppChooserButton *self)
{
GtkWidget *dialog, *widget;
GtkWindow *toplevel;
toplevel = GTK_WINDOW (gtk_widget_get_toplevel (GTK_WIDGET (self)));
dialog = gtk_app_chooser_dialog_new_for_content_type (toplevel, GTK_DIALOG_DESTROY_WITH_PARENT,
self->priv->content_type);
gtk_window_set_modal (GTK_WINDOW (dialog), gtk_window_get_modal (toplevel));
gtk_app_chooser_dialog_set_heading (GTK_APP_CHOOSER_DIALOG (dialog),
self->priv->heading);
widget = gtk_app_chooser_dialog_get_widget (GTK_APP_CHOOSER_DIALOG (dialog));
g_object_set (widget,
"show-fallback", TRUE,
"show-other", TRUE,
NULL);
gtk_widget_show (dialog);
g_signal_connect (dialog, "response",
G_CALLBACK (other_application_dialog_response_cb), self);
}
static void
gtk_app_chooser_button_ensure_dialog_item (GtkAppChooserButton *self,
GtkTreeIter *prev_iter)
{
GtkTreeIter iter, iter2;
if (!self->priv->show_dialog_item || !self->priv->content_type)
return;
if (prev_iter == NULL)
gtk_list_store_append (self->priv->store, &iter);
else
gtk_list_store_insert_after (self->priv->store, &iter, prev_iter);
real_insert_separator (self, FALSE, &iter);
iter2 = iter;
gtk_list_store_insert_after (self->priv->store, &iter, &iter2);
real_insert_custom_item (self, CUSTOM_ITEM_OTHER_APP,
_("Other application..."), NULL,
FALSE, &iter);
}
static void
gtk_app_chooser_button_populate (GtkAppChooserButton *self)
{
GList *recommended_apps = NULL, *l;
GAppInfo *app;
GtkTreeIter iter, iter2;
GIcon *icon;
gboolean cycled_recommended;
#ifndef G_OS_WIN32
if (self->priv->content_type)
recommended_apps = g_app_info_get_recommended_for_type (self->priv->content_type);
#endif
cycled_recommended = FALSE;
for (l = recommended_apps; l != NULL; l = l->next)
{
app = l->data;
icon = g_app_info_get_icon (app);
if (icon == NULL)
icon = g_themed_icon_new ("application-x-executable");
else
g_object_ref (icon);
if (cycled_recommended)
{
gtk_list_store_insert_after (self->priv->store, &iter2, &iter);
iter = iter2;
}
else
{
get_first_iter (self->priv->store, &iter);
cycled_recommended = TRUE;
}
gtk_list_store_set (self->priv->store, &iter,
COLUMN_APP_INFO, app,
COLUMN_LABEL, g_app_info_get_name (app),
COLUMN_ICON, icon,
COLUMN_CUSTOM, FALSE,
-1);
g_object_unref (icon);
}
if (!cycled_recommended)
gtk_app_chooser_button_ensure_dialog_item (self, NULL);
else
gtk_app_chooser_button_ensure_dialog_item (self, &iter);
gtk_combo_box_set_active (GTK_COMBO_BOX (self), 0);
}
static void
gtk_app_chooser_button_build_ui (GtkAppChooserButton *self)
{
GtkCellRenderer *cell;
GtkCellArea *area;
gtk_combo_box_set_model (GTK_COMBO_BOX (self),
GTK_TREE_MODEL (self->priv->store));
area = gtk_cell_layout_get_area (GTK_CELL_LAYOUT (self));
gtk_combo_box_set_row_separator_func (GTK_COMBO_BOX (self),
row_separator_func, NULL, NULL);
cell = gtk_cell_renderer_pixbuf_new ();
gtk_cell_area_add_with_properties (area, cell,
"align", FALSE,
"expand", FALSE,
"fixed-size", FALSE,
NULL);
gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (self), cell,
"gicon", COLUMN_ICON,
NULL);
cell = gtk_cell_renderer_text_new ();
gtk_cell_area_add_with_properties (area, cell,
"align", FALSE,
"expand", TRUE,
NULL);
gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (self), cell,
"text", COLUMN_LABEL,
NULL);
gtk_app_chooser_button_populate (self);
}
static void
gtk_app_chooser_button_remove_non_custom (GtkAppChooserButton *self)
{
GtkTreeModel *model;
GtkTreeIter iter;
gboolean custom, res;
model = GTK_TREE_MODEL (self->priv->store);
if (!gtk_tree_model_get_iter_first (model, &iter))
return;
do {
gtk_tree_model_get (model, &iter,
COLUMN_CUSTOM, &custom,
-1);
if (custom)
res = gtk_tree_model_iter_next (model, &iter);
else
res = gtk_list_store_remove (GTK_LIST_STORE (model), &iter);
} while (res);
}
static void
gtk_app_chooser_button_changed (GtkComboBox *object)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (object);
GtkTreeIter iter;
gchar *name = NULL;
gboolean custom;
GQuark name_quark;
if (!gtk_combo_box_get_active_iter (object, &iter))
return;
gtk_tree_model_get (GTK_TREE_MODEL (self->priv->store), &iter,
COLUMN_NAME, &name,
COLUMN_CUSTOM, &custom,
-1);
if (name != NULL)
{
if (custom)
{
name_quark = g_quark_from_string (name);
g_signal_emit (self, signals[SIGNAL_CUSTOM_ITEM_ACTIVATED], name_quark, name);
self->priv->last_active = gtk_combo_box_get_active (object);
}
else
{
/* trigger the dialog internally */
other_application_item_activated_cb (self);
}
g_free (name);
}
else
self->priv->last_active = gtk_combo_box_get_active (object);
}
static void
gtk_app_chooser_button_refresh (GtkAppChooser *object)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (object);
gtk_app_chooser_button_remove_non_custom (self);
gtk_app_chooser_button_populate (self);
}
static GAppInfo *
gtk_app_chooser_button_get_app_info (GtkAppChooser *object)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (object);
GtkTreeIter iter;
GAppInfo *info;
if (!gtk_combo_box_get_active_iter (GTK_COMBO_BOX (self), &iter))
return NULL;
gtk_tree_model_get (GTK_TREE_MODEL (self->priv->store), &iter,
COLUMN_APP_INFO, &info,
-1);
return info;
}
static void
gtk_app_chooser_button_constructed (GObject *obj)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (obj);
if (G_OBJECT_CLASS (gtk_app_chooser_button_parent_class)->constructed != NULL)
G_OBJECT_CLASS (gtk_app_chooser_button_parent_class)->constructed (obj);
gtk_app_chooser_button_build_ui (self);
}
static void
gtk_app_chooser_button_set_property (GObject *obj,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (obj);
switch (property_id)
{
case PROP_CONTENT_TYPE:
self->priv->content_type = g_value_dup_string (value);
break;
case PROP_SHOW_DIALOG_ITEM:
gtk_app_chooser_button_set_show_dialog_item (self, g_value_get_boolean (value));
break;
case PROP_HEADING:
gtk_app_chooser_button_set_heading (self, g_value_get_string (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, property_id, pspec);
break;
}
}
static void
gtk_app_chooser_button_get_property (GObject *obj,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (obj);
switch (property_id)
{
case PROP_CONTENT_TYPE:
g_value_set_string (value, self->priv->content_type);
break;
case PROP_SHOW_DIALOG_ITEM:
g_value_set_boolean (value, self->priv->show_dialog_item);
break;
case PROP_HEADING:
g_value_set_string (value, self->priv->heading);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (obj, property_id, pspec);
break;
}
}
static void
gtk_app_chooser_button_finalize (GObject *obj)
{
GtkAppChooserButton *self = GTK_APP_CHOOSER_BUTTON (obj);
g_hash_table_destroy (self->priv->custom_item_names);
g_free (self->priv->content_type);
g_free (self->priv->heading);
g_object_unref (self->priv->store);
G_OBJECT_CLASS (gtk_app_chooser_button_parent_class)->finalize (obj);
}
static void
app_chooser_iface_init (GtkAppChooserIface *iface)
{
iface->get_app_info = gtk_app_chooser_button_get_app_info;
iface->refresh = gtk_app_chooser_button_refresh;
}
static void
gtk_app_chooser_button_class_init (GtkAppChooserButtonClass *klass)
{
GObjectClass *oclass = G_OBJECT_CLASS (klass);
GtkComboBoxClass *combo_class = GTK_COMBO_BOX_CLASS (klass);
GParamSpec *pspec;
oclass->set_property = gtk_app_chooser_button_set_property;
oclass->get_property = gtk_app_chooser_button_get_property;
oclass->finalize = gtk_app_chooser_button_finalize;
oclass->constructed = gtk_app_chooser_button_constructed;
combo_class->changed = gtk_app_chooser_button_changed;
g_object_class_override_property (oclass, PROP_CONTENT_TYPE, "content-type");
/**
* GtkAppChooserButton:show-dialog-item:
*
* The #GtkAppChooserButton:show-dialog-item property determines whether the dropdown menu
* should show an item that triggers a #GtkAppChooserDialog when clicked.
*/
pspec =
g_param_spec_boolean ("show-dialog-item",
P_("Include an 'Other...' item"),
P_("Whether the combobox should include an item that triggers a GtkAppChooserDialog"),
FALSE,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS);
g_object_class_install_property (oclass, PROP_SHOW_DIALOG_ITEM, pspec);
/**
* GtkAppChooserButton:heading:
*
* The text to show at the top of the dialog that can be
* opened from the button. The string may contain Pango markup.
*/
pspec = g_param_spec_string ("heading",
P_("Heading"),
P_("The text to show at the top of the dialog"),
NULL,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
g_object_class_install_property (oclass, PROP_HEADING, pspec);
/**
* GtkAppChooserButton::custom-item-activated:
* @self: the object which received the signal
* @item_name: the name of the activated item
*
* Emitted when a custom item, previously added with
* gtk_app_chooser_button_append_custom_item(), is activated from the
* dropdown menu.
*/
signals[SIGNAL_CUSTOM_ITEM_ACTIVATED] =
g_signal_new ("custom-item-activated",
GTK_TYPE_APP_CHOOSER_BUTTON,
G_SIGNAL_RUN_FIRST | G_SIGNAL_DETAILED,
G_STRUCT_OFFSET (GtkAppChooserButtonClass, custom_item_activated),
NULL, NULL,
_gtk_marshal_VOID__STRING,
G_TYPE_NONE,
1, G_TYPE_STRING);
g_type_class_add_private (klass, sizeof (GtkAppChooserButtonPrivate));
}
static void
gtk_app_chooser_button_init (GtkAppChooserButton *self)
{
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, GTK_TYPE_APP_CHOOSER_BUTTON,
GtkAppChooserButtonPrivate);
self->priv->custom_item_names =
g_hash_table_new_full (g_str_hash, g_str_equal,
g_free, NULL);
self->priv->store = gtk_list_store_new (NUM_COLUMNS,
G_TYPE_APP_INFO,
G_TYPE_STRING, /* name */
G_TYPE_STRING, /* label */
G_TYPE_ICON,
G_TYPE_BOOLEAN, /* separator */
G_TYPE_BOOLEAN); /* custom */
}
static gboolean
app_chooser_button_iter_from_custom_name (GtkAppChooserButton *self,
const gchar *name,
GtkTreeIter *set_me)
{
GtkTreeIter iter;
gchar *custom_name = NULL;
if (!gtk_tree_model_get_iter_first
(GTK_TREE_MODEL (self->priv->store), &iter))
return FALSE;
do {
gtk_tree_model_get (GTK_TREE_MODEL (self->priv->store), &iter,
COLUMN_NAME, &custom_name,
-1);
if (g_strcmp0 (custom_name, name) == 0)
{
g_free (custom_name);
*set_me = iter;
return TRUE;
}
g_free (custom_name);
} while (gtk_tree_model_iter_next (GTK_TREE_MODEL (self->priv->store), &iter));
return FALSE;
}
static void
real_insert_custom_item (GtkAppChooserButton *self,
const gchar *name,
const gchar *label,
GIcon *icon,
gboolean custom,
GtkTreeIter *iter)
{
if (custom)
{
if (g_hash_table_lookup (self->priv->custom_item_names,
name) != NULL)
{
g_warning ("Attempting to add custom item %s to GtkAppChooserButton, "
"when there's already an item with the same name", name);
return;
}
g_hash_table_insert (self->priv->custom_item_names,
g_strdup (name), GINT_TO_POINTER (1));
}
gtk_list_store_set (self->priv->store, iter,
COLUMN_NAME, name,
COLUMN_LABEL, label,
COLUMN_ICON, icon,
COLUMN_CUSTOM, custom,
COLUMN_SEPARATOR, FALSE,
-1);
}
static void
real_insert_separator (GtkAppChooserButton *self,
gboolean custom,
GtkTreeIter *iter)
{
gtk_list_store_set (self->priv->store, iter,
COLUMN_CUSTOM, custom,
COLUMN_SEPARATOR, TRUE,
-1);
}
/**
* gtk_app_chooser_button_new:
* @content_type: the content type to show applications for
*
* Creates a new #GtkAppChooserButton for applications
* that can handle content of the given type.
*
* Returns: a newly created #GtkAppChooserButton
*
* Since: 3.0
*/
GtkWidget *
gtk_app_chooser_button_new (const gchar *content_type)
{
g_return_val_if_fail (content_type != NULL, NULL);
return g_object_new (GTK_TYPE_APP_CHOOSER_BUTTON,
"content-type", content_type,
NULL);
}
/**
* gtk_app_chooser_button_append_separator:
* @self: a #GtkAppChooserButton
*
* Appends a separator to the list of applications that is shown
* in the popup.
*
* Since: 3.0
*/
void
gtk_app_chooser_button_append_separator (GtkAppChooserButton *self)
{
GtkTreeIter iter;
g_return_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self));
gtk_list_store_append (self->priv->store, &iter);
real_insert_separator (self, TRUE, &iter);
}
/**
* gtk_app_chooser_button_append_custom_item:
* @self: a #GtkAppChooserButton
* @name: the name of the custom item
* @label: the label for the custom item
* @icon: the icon for the custom item
*
* Appends a custom item to the list of applications that is shown
* in the popup; the item name must be unique per-widget.
* Clients can use the provided name as a detail for the ::custom-item-activated
* signal, to add a callback for the activation of a particular
* custom item in the list.
* See also gtk_app_chooser_button_append_separator().
*
* Since: 3.0
*/
void
gtk_app_chooser_button_append_custom_item (GtkAppChooserButton *self,
const gchar *name,
const gchar *label,
GIcon *icon)
{
GtkTreeIter iter;
g_return_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self));
g_return_if_fail (name != NULL);
gtk_list_store_append (self->priv->store, &iter);
real_insert_custom_item (self, name, label, icon, TRUE, &iter);
}
/**
* gtk_app_chooser_button_set_active_custom_item:
* @self: a #GtkAppChooserButton
* @name: the name of the custom item
*
* Selects a custom item previously added with
* gtk_app_chooser_button_append_custom_item().
*
* Use gtk_app_chooser_refresh() to bring the selection
* to its initial state.
*
* Since: 3.0
*/
void
gtk_app_chooser_button_set_active_custom_item (GtkAppChooserButton *self,
const gchar *name)
{
GtkTreeIter iter;
g_return_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self));
g_return_if_fail (name != NULL);
if (g_hash_table_lookup (self->priv->custom_item_names, name) == NULL ||
!app_chooser_button_iter_from_custom_name (self, name, &iter))
{
g_warning ("Can't find the item named %s in the app chooser.",
name);
return;
}
gtk_combo_box_set_active_iter (GTK_COMBO_BOX (self), &iter);
}
/**
* gtk_app_chooser_button_get_show_dialog_item:
* @self: a #GtkAppChooserButton
*
* Returns the current value of the #GtkAppChooserButton:show-dialog-item
* property.
*
* Returns: the value of #GtkAppChooserButton:show-dialog-item
*
* Since: 3.0
*/
gboolean
gtk_app_chooser_button_get_show_dialog_item (GtkAppChooserButton *self)
{
g_return_val_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self), FALSE);
return self->priv->show_dialog_item;
}
/**
* gtk_app_chooser_button_set_show_dialog_item:
* @self: a #GtkAppChooserButton
* @setting: the new value for #GtkAppChooserButton:show-dialog-item
*
* Sets whether the dropdown menu of this button should show an
* entry to trigger a #GtkAppChooserDialog.
*
* Since: 3.0
*/
void
gtk_app_chooser_button_set_show_dialog_item (GtkAppChooserButton *self,
gboolean setting)
{
if (self->priv->show_dialog_item != setting)
{
self->priv->show_dialog_item = setting;
g_object_notify (G_OBJECT (self), "show-dialog-item");
gtk_app_chooser_refresh (GTK_APP_CHOOSER (self));
}
}
/**
* gtk_app_chooser_button_set_heading:
* @self: a #GtkAppChooserButton
* @heading: a string containing Pango markup
*
* Sets the text to display at the top of the dialog.
* If the heading is not set, the dialog displays a default text.
*/
void
gtk_app_chooser_button_set_heading (GtkAppChooserButton *self,
const gchar *heading)
{
g_return_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self));
g_free (self->priv->heading);
self->priv->heading = g_strdup (heading);
g_object_notify (G_OBJECT (self), "heading");
}
/**
* gtk_app_chooser_button_get_heading:
* @self: a #GtkAppChooserButton
*
* Returns the text to display at the top of the dialog.
*
* Returns: the text to display at the top of the dialog, or %NULL, in which
* case a default text is displayed
*/
const gchar *
gtk_app_chooser_button_get_heading (GtkAppChooserButton *self)
{
g_return_val_if_fail (GTK_IS_APP_CHOOSER_BUTTON (self), NULL);
return self->priv->heading;
}