[tepl] StyleSchemeChooserWidget: listen to scheme manager changes

[Sébastien Wilmet <swilmet src gnome org>]

commit 1bdd35bc8618b5b4bca756478d3238005feba164
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Thu Apr 23 14:17:31 2020 +0200

    StyleSchemeChooserWidget: listen to scheme manager changes

 tepl/tepl-style-scheme-chooser-widget.c | 78 +++++++++++++++++++++++++++++++--
 1 file changed, 74 insertions(+), 4 deletions(-)
---
diff --git a/tepl/tepl-style-scheme-chooser-widget.c b/tepl/tepl-style-scheme-chooser-widget.c
index e2c2b9c..1db3b46 100644
--- a/tepl/tepl-style-scheme-chooser-widget.c
+++ b/tepl/tepl-style-scheme-chooser-widget.c
@@ -60,6 +60,21 @@ G_DEFINE_TYPE_WITH_CODE (TeplStyleSchemeChooserWidget,
                         G_IMPLEMENT_INTERFACE (GTK_SOURCE_TYPE_STYLE_SCHEME_CHOOSER,
                                                gtk_source_style_scheme_chooser_interface_init))
 
+static void
+clear_list_box_foreach_cb (GtkWidget *child,
+                          gpointer   user_data)
+{
+       gtk_widget_destroy (child);
+}
+
+static void
+clear_list_box (GtkListBox *list_box)
+{
+       gtk_container_foreach (GTK_CONTAINER (list_box),
+                              clear_list_box_foreach_cb,
+                              NULL);
+}
+
 static void
 list_box_row_set_style_scheme (GtkListBoxRow        *list_box_row,
                               GtkSourceStyleScheme *style_scheme)
@@ -313,6 +328,7 @@ append_style_scheme_to_list_box (TeplStyleSchemeChooserWidget *chooser,
        list_box_row = gtk_list_box_row_new ();
        gtk_container_add (GTK_CONTAINER (list_box_row), label);
        list_box_row_set_style_scheme (GTK_LIST_BOX_ROW (list_box_row), style_scheme);
+       gtk_widget_show_all (list_box_row);
 
        gtk_list_box_insert (chooser->priv->list_box, list_box_row, -1);
 
@@ -320,7 +336,7 @@ append_style_scheme_to_list_box (TeplStyleSchemeChooserWidget *chooser,
 }
 
 static void
-fill_list_box (TeplStyleSchemeChooserWidget *chooser)
+populate_list_box (TeplStyleSchemeChooserWidget *chooser)
 {
        GtkSourceStyleSchemeManager *manager;
        const gchar * const *scheme_ids;
@@ -345,13 +361,66 @@ fill_list_box (TeplStyleSchemeChooserWidget *chooser)
 }
 
 static void
-list_box_selected_rows_changed_cb (GtkListBox                   *list_box,
-                                  TeplStyleSchemeChooserWidget *chooser)
+notify_properties (TeplStyleSchemeChooserWidget *chooser)
 {
        g_object_notify (G_OBJECT (chooser), "style-scheme");
        g_object_notify (G_OBJECT (chooser), "tepl-style-scheme-id");
 }
 
+static void
+list_box_selected_rows_changed_cb (GtkListBox                   *list_box,
+                                  TeplStyleSchemeChooserWidget *chooser)
+{
+       notify_properties (chooser);
+}
+
+static void
+style_scheme_manager_notify_scheme_ids_cb (GtkSourceStyleSchemeManager  *manager,
+                                          GParamSpec                   *pspec,
+                                          TeplStyleSchemeChooserWidget *chooser)
+{
+       gchar *style_scheme_id;
+
+       g_signal_handlers_block_by_func (chooser->priv->list_box,
+                                        list_box_selected_rows_changed_cb,
+                                        chooser);
+
+       style_scheme_id = tepl_style_scheme_chooser_widget_get_style_scheme_id (chooser);
+
+       clear_list_box (chooser->priv->list_box);
+       populate_list_box (chooser);
+
+       /* Note that the style_scheme_id may no longer exist, in which case no
+        * rows will be selected.
+        */
+       tepl_style_scheme_chooser_widget_set_style_scheme_id (chooser, style_scheme_id);
+
+       scroll_to_selected_row (chooser->priv->list_box);
+
+       g_signal_handlers_unblock_by_func (chooser->priv->list_box,
+                                          list_box_selected_rows_changed_cb,
+                                          chooser);
+
+       /* Notify properies in all cases, even if no rows are selected. */
+       notify_properties (chooser);
+
+       g_free (style_scheme_id);
+}
+
+static void
+listen_to_scheme_manager_changes (TeplStyleSchemeChooserWidget *chooser)
+{
+       GtkSourceStyleSchemeManager *manager;
+
+       manager = gtk_source_style_scheme_manager_get_default ();
+
+       g_signal_connect_object (manager,
+                                "notify::scheme-ids",
+                                G_CALLBACK (style_scheme_manager_notify_scheme_ids_cb),
+                                chooser,
+                                0);
+}
+
 static void
 tepl_style_scheme_chooser_widget_init (TeplStyleSchemeChooserWidget *chooser)
 {
@@ -363,7 +432,8 @@ tepl_style_scheme_chooser_widget_init (TeplStyleSchemeChooserWidget *chooser)
        chooser->priv->list_box = GTK_LIST_BOX (gtk_list_box_new ());
        gtk_list_box_set_selection_mode (chooser->priv->list_box, GTK_SELECTION_BROWSE);
 
-       fill_list_box (chooser);
+       populate_list_box (chooser);
+       listen_to_scheme_manager_changes (chooser);
 
        scrolled_window = gtk_scrolled_window_new (NULL, NULL);
        gtk_widget_set_hexpand (scrolled_window, TRUE);