[evolution] [ETimezoneDialog] Show timezones as a tree, not as a flat list

[Milan Crha <mcrha src gnome org>]

commit 172b35e7633ac6ba7981ee4c810fd8e58ebf47f4
Author: Milan Crha <mcrha redhat com>
Date:   Mon Jul 4 21:53:32 2016 +0200

    [ETimezoneDialog] Show timezones as a tree, not as a flat list
    
    This will make it easier to find the time zone, because it makes
    them divided into levels according to the name split by a slash.

 e-util/e-timezone-dialog.c |  141 +++++++++++++++++++++++++++++++++-----------
 1 files changed, 106 insertions(+), 35 deletions(-)
---
diff --git a/e-util/e-timezone-dialog.c b/e-util/e-timezone-dialog.c
index bb2aa21..c4a56ed 100644
--- a/e-util/e-timezone-dialog.c
+++ b/e-util/e-timezone-dialog.c
@@ -68,6 +68,7 @@ struct _ETimezoneDialogPrivate {
        EMapPoint *point_hover;
 
        EMap *map;
+       GHashTable *index; /* const gchar *location ~> GtkTreeIter * */
 
        /* The timeout used to flash the nearest point. */
        guint timeout_id;
@@ -106,7 +107,7 @@ static void on_combo_changed                (GtkComboBox    *combo,
 
 static void timezone_combo_get_active_text     (GtkComboBox *combo,
                                                 gchar **zone_name);
-static gboolean timezone_combo_set_active_text (GtkComboBox *combo,
+static gboolean timezone_combo_set_active_text (ETimezoneDialog *etd,
                                                 const gchar *zone_name);
 
 static void    map_destroy_cb                  (gpointer data,
@@ -131,6 +132,7 @@ static void
 e_timezone_dialog_init (ETimezoneDialog *etd)
 {
        etd->priv = E_TIMEZONE_DIALOG_GET_PRIVATE (etd);
+       etd->priv->index = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, g_free);
 }
 
 /* Dispose handler for the event editor */
@@ -157,10 +159,64 @@ e_timezone_dialog_dispose (GObject *object)
                priv->builder = NULL;
        }
 
+       if (priv->index) {
+               g_hash_table_destroy (priv->index);
+               priv->index = NULL;
+       }
+
        /* Chain up to parent's dispose() method. */
        G_OBJECT_CLASS (e_timezone_dialog_parent_class)->dispose (object);
 }
 
+static GtkTreeIter *
+e_timezone_dialog_ensure_parent (GtkTreeStore *tree_store,
+                                GHashTable *parents,
+                                const gchar *location,
+                                const gchar **name)
+{
+       GtkTreeIter *parent = NULL;
+       const gchar *slash, *lookup_from;
+       gchar *part;
+
+       g_return_val_if_fail (GTK_IS_TREE_STORE (tree_store), NULL);
+       g_return_val_if_fail (parents != NULL, NULL);
+       g_return_val_if_fail (name != NULL, NULL);
+
+       if (!location)
+               return NULL;
+
+       *name = location;
+       lookup_from = location;
+
+       while (slash = strchr (lookup_from, '/'), slash) {
+               GtkTreeIter *new_parent;
+               gchar *full_part;
+
+               *name = slash + 1;
+               full_part = g_strndup (location, slash - location);
+               part = g_strndup (lookup_from, slash - lookup_from);
+
+               new_parent = g_hash_table_lookup (parents, full_part);
+               if (!new_parent) {
+                       new_parent = g_new (GtkTreeIter, 1);
+
+                       gtk_tree_store_append (tree_store, new_parent, parent);
+                       gtk_tree_store_set (tree_store, new_parent, 0, part, -1);
+
+                       g_hash_table_insert (parents, full_part, new_parent);
+               } else {
+                       g_free (full_part);
+               }
+
+               g_free (part);
+
+               parent = new_parent;
+               lookup_from = slash + 1;
+       }
+
+       return parent;
+}
+
 static void
 e_timezone_dialog_add_timezones (ETimezoneDialog *etd)
 {
@@ -168,18 +224,20 @@ e_timezone_dialog_add_timezones (ETimezoneDialog *etd)
        icalarray *zones;
        GtkComboBox *combo;
        GList *l, *list_items = NULL;
-       GtkListStore *list_store;
+       GtkTreeStore *tree_store;
        GtkTreeIter iter;
        GtkCellRenderer *cell;
        GtkCssProvider *css_provider;
        GtkStyleContext *style_context;
-       GHashTable *index;
+       GHashTable *parents;
        const gchar *css;
        gint i;
        GError *error = NULL;
 
        priv = etd->priv;
 
+       g_hash_table_remove_all (priv->index);
+
        /* Get the array of builtin timezones. */
        zones = icaltimezone_get_builtin_timezones ();
 
@@ -207,23 +265,41 @@ e_timezone_dialog_add_timezones (ETimezoneDialog *etd)
 
        combo = GTK_COMBO_BOX (priv->timezone_combo);
 
+       gtk_cell_layout_clear (GTK_CELL_LAYOUT (combo));
+
+       cell = gtk_cell_renderer_text_new ();
+       gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (combo), cell, TRUE);
+       gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (combo), cell, "text", 0, NULL);
+
+       e_binding_bind_property (combo, "popup-shown", cell, "visible", G_BINDING_SYNC_CREATE);
+
        cell = gtk_cell_renderer_text_new ();
-       gtk_cell_layout_pack_start ((GtkCellLayout *) combo, cell, TRUE);
-       gtk_cell_layout_set_attributes ((GtkCellLayout *) combo, cell, "text", 0, NULL);
+       gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (combo), cell, TRUE);
+       gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (combo), cell, "text", 1, NULL);
 
-       list_store = gtk_list_store_new (1, G_TYPE_STRING);
-       index = g_hash_table_new (g_str_hash, g_str_equal);
+       e_binding_bind_property (combo, "popup-shown", cell, "visible", G_BINDING_SYNC_CREATE | 
G_BINDING_INVERT_BOOLEAN);
+
+       parents = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
+
+       tree_store = gtk_tree_store_new (2, G_TYPE_STRING, G_TYPE_STRING);
        for (l = list_items, i = 0; l != NULL; l = l->next, ++i) {
-               gtk_list_store_append (list_store, &iter);
-               gtk_list_store_set (list_store, &iter, 0, (gchar *)(l->data), -1);
-               g_hash_table_insert (index, (gchar *)(l->data), GINT_TO_POINTER (i));
+               GtkTreeIter *piter, *parent = NULL;
+               const gchar *name = NULL;
+               const gchar *location = l->data;
+
+               parent = e_timezone_dialog_ensure_parent (tree_store, parents, location, &name);
+               gtk_tree_store_append (tree_store, &iter, parent);
+               gtk_tree_store_set (tree_store, &iter, 0, (gchar *) name, 1, (gchar *) location, -1);
+
+               piter = g_new (GtkTreeIter, 1);
+               *piter = iter;
+
+               g_hash_table_insert (priv->index, (gchar *) location, piter);
        }
 
-       g_object_set_data_full (
-               G_OBJECT (list_store), "index", index,
-               (GDestroyNotify) g_hash_table_destroy);
+       g_hash_table_destroy (parents);
 
-       gtk_combo_box_set_model (combo, (GtkTreeModel *) list_store);
+       gtk_combo_box_set_model (combo, GTK_TREE_MODEL (tree_store));
 
        css_provider = gtk_css_provider_new ();
        css = "GtkComboBox { -GtkComboBox-appears-as-list: 1; }";
@@ -561,9 +637,7 @@ on_map_leave (GtkWidget *widget,
                        priv->map, priv->point_hover,
                        E_TIMEZONE_DIALOG_MAP_POINT_NORMAL_RGBA);
 
-       timezone_combo_set_active_text (
-               GTK_COMBO_BOX (priv->timezone_combo),
-               zone_display_name (priv->zone));
+       timezone_combo_set_active_text (etd, zone_display_name (priv->zone));
        gtk_label_set_text (GTK_LABEL (priv->preview_label), "");
 
        priv->point_hover = NULL;
@@ -636,9 +710,7 @@ on_map_button_pressed (GtkWidget *w,
                priv->point_selected = priv->point_hover;
 
                priv->zone = get_zone_from_point (etd, priv->point_selected);
-               timezone_combo_set_active_text (
-                       GTK_COMBO_BOX (priv->timezone_combo),
-                       zone_display_name (priv->zone));
+               timezone_combo_set_active_text (etd, zone_display_name (priv->zone));
        }
 
        return TRUE;
@@ -733,9 +805,7 @@ e_timezone_dialog_set_timezone (ETimezoneDialog *etd,
        gtk_label_set_text (
                GTK_LABEL (priv->preview_label),
                zone ? display : "");
-       timezone_combo_set_active_text (
-               GTK_COMBO_BOX (priv->timezone_combo),
-               zone ? zone_display_name (zone) : "");
+       timezone_combo_set_active_text (etd, zone ? zone_display_name (zone) : "");
 
        set_map_timezone (etd, zone);
        g_free (display);
@@ -826,35 +896,36 @@ static void
 timezone_combo_get_active_text (GtkComboBox *combo,
                                 gchar **zone_name)
 {
-       GtkTreeModel *list_store;
+       GtkTreeModel *tree_store;
        GtkTreeIter iter;
 
-       list_store = gtk_combo_box_get_model (combo);
+       tree_store = gtk_combo_box_get_model (combo);
 
        /* Get the active iter in the list */
        if (gtk_combo_box_get_active_iter (combo, &iter))
-               gtk_tree_model_get (list_store, &iter, 0, zone_name, -1);
+               gtk_tree_model_get (tree_store, &iter, 1, zone_name, -1);
        else
                *zone_name = NULL;
 }
 
 static gboolean
-timezone_combo_set_active_text (GtkComboBox *combo,
+timezone_combo_set_active_text (ETimezoneDialog *etd,
                                 const gchar *zone_name)
 {
-       GtkTreeModel *list_store;
-       GHashTable *index;
-       gpointer id = NULL;
+       GtkTreeIter *piter = NULL;
+       GtkComboBox *combo;
 
-       list_store = gtk_combo_box_get_model (combo);
-       index = (GHashTable *) g_object_get_data (G_OBJECT (list_store), "index");
+       combo = GTK_COMBO_BOX (etd->priv->timezone_combo);
 
        if (zone_name && *zone_name)
-               id = g_hash_table_lookup (index, zone_name);
+               piter = g_hash_table_lookup (etd->priv->index, zone_name);
 
-       gtk_combo_box_set_active (combo, GPOINTER_TO_INT (id));
+       if (piter)
+               gtk_combo_box_set_active_iter (combo, piter);
+       else
+               gtk_combo_box_set_active (combo, 0);
 
-       return (id != NULL);
+       return piter != NULL;
 }
 
 static void