Add GtkStringList as public api

This is a list model holding strings, initialized
from a char **. String lists are buildable as well,
and that replaces the buildable support in GktDropDowns.

6 files changed, 732 insertions, 345 deletions

diff --git a/gtk/gtk.h b/gtk/gtk.h
index b7600866f9..0ab53bfd33 100644
--- a/gtk/gtk.h
+++ b/gtk/gtk.h
@@ -243,6 +243,7 @@
 #include <gtk/gtkstackswitcher.h>
 #include <gtk/gtkstatusbar.h>
 #include <gtk/gtkstringfilter.h>
+#include <gtk/gtkstringlist.h>
 #include <gtk/gtkstringsorter.h>
 #include <gtk/gtkstylecontext.h>
 #include <gtk/gtkstyleprovider.h>
diff --git a/gtk/gtkdropdown.c b/gtk/gtkdropdown.c
index ef151e7203..8430c1450b 100644
--- a/gtk/gtkdropdown.c
+++ b/gtk/gtkdropdown.c
@@ -44,6 +44,7 @@
 #include "gtklistitem.h"
 #include "gtkbuildable.h"
 #include "gtkbuilderprivate.h"
+#include "gtkstringlist.h"
 
 /**
  * SECTION:gtkdropdown
@@ -69,26 +70,6 @@
  * useful if the list of options is long. To enable the search entry,
  * use gtk_drop_down_set_enable_search().
  *
- * # GtkDropDown as GtkBuildable
- *
- * The GtkDropDown implementation of the GtkBuildable interface supports
- * adding items directly using the <items> element and specifying <item>
- * elements for each item. Using <items> is equivalent to calling
- * gtk_drop_down_set_from_strings(). Each <item> element supports
- * the regular translation attributes “translatable”, “context”
- * and “comments”.
- *
- * Here is a UI definition fragment specifying GtkDropDown items:
- * |[
- * <object class="GtkDropDown">
- *   <items>
- *     <item translatable="yes">Factory</item>
- *     <item translatable="yes">Home</item>
- *     <item translatable="yes">Subway</item>
- *   </items>
- * </object>
- * ]|
- *
  * * # CSS nodes
  *
  * GtkDropDown has a single CSS node with name dropdown,
@@ -138,13 +119,7 @@ enum
   N_PROPS
 };
 
-static void gtk_drop_down_buildable_interface_init (GtkBuildableIface *iface);
-
-static GtkBuildableIface *buildable_parent_iface = NULL;
-
-G_DEFINE_TYPE_WITH_CODE (GtkDropDown, gtk_drop_down, GTK_TYPE_WIDGET,
-                         G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE,
-                                                gtk_drop_down_buildable_interface_init))
+G_DEFINE_TYPE (GtkDropDown, gtk_drop_down, GTK_TYPE_WIDGET)
 
 static GParamSpec *properties[N_PROPS] = { NULL, };
 
@@ -577,20 +552,26 @@ bind_item (GtkSignalListItemFactory *factory,
   GtkWidget *label;
   GValue value = G_VALUE_INIT;
 
-  if (self->expression == NULL)
-    {
-      g_critical ("Either GtkDropDown::factory or GtkDropDown::expression must be set");
-      return;
-    }
-
   item = gtk_list_item_get_item (list_item);
   label = gtk_list_item_get_child (list_item);
 
-  if (gtk_expression_evaluate (self->expression, item, &value))
+  if (self->expression &&
+      gtk_expression_evaluate (self->expression, item, &value))
     {
       gtk_label_set_label (GTK_LABEL (label), g_value_get_string (&value));
       g_value_unset (&value);
     }
+  else if (GTK_IS_STRING_OBJECT (item))
+    {
+      const char *string;
+
+      string = gtk_string_object_get_string (GTK_STRING_OBJECT (item));
+      gtk_label_set_label (GTK_LABEL (label), string);
+    }
+  else
+    {
+      g_critical ("Either GtkDropDown:factory or GtkDropDown:expression must be set");
+    }
 }
 
 static void
@@ -943,118 +924,6 @@ gtk_drop_down_get_expression (GtkDropDown *self)
   return self->expression;
 }
 
-
-#define GTK_TYPE_DROP_DOWN_STRING_HOLDER (gtk_drop_down_string_holder_get_type ())
-G_DECLARE_FINAL_TYPE (GtkDropDownStringHolder, gtk_drop_down_string_holder, GTK, DROP_DOWN_STRING_HOLDER, GObject)
-
-struct _GtkDropDownStringHolder {
-  GObject parent_instance;
-  char *string;
-};
-
-enum {
-  PROP_STRING = 1,
-  PROP_NUM_PROPERTIES
-};
-
-G_DEFINE_TYPE (GtkDropDownStringHolder, gtk_drop_down_string_holder, G_TYPE_OBJECT);
-
-static void
-gtk_drop_down_string_holder_init (GtkDropDownStringHolder *holder)
-{
-}
-
-static void
-gtk_drop_down_string_holder_finalize (GObject *object)
-{
-  GtkDropDownStringHolder *holder = GTK_DROP_DOWN_STRING_HOLDER (object);
-
-  g_free (holder->string);
-
-  G_OBJECT_CLASS (gtk_drop_down_string_holder_parent_class)->finalize (object);
-}
-
-static void
-gtk_drop_down_string_holder_set_property (GObject      *object,
-                                          guint         property_id,
-                                          const GValue *value,
-                                          GParamSpec   *pspec)
-{
-  GtkDropDownStringHolder *holder = GTK_DROP_DOWN_STRING_HOLDER (object);
-
-  switch (property_id)
-    {
-    case PROP_STRING:
-      g_free (holder->string);
-      holder->string = g_value_dup_string (value);
-      break;
-
-    default:
-      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
-      break;
-    }
-}
-
-static void
-gtk_drop_down_string_holder_get_property (GObject      *object,
-                                          guint         property_id,
-                                          GValue       *value,
-                                          GParamSpec   *pspec)
-{
-  GtkDropDownStringHolder *holder = GTK_DROP_DOWN_STRING_HOLDER (object);
-
-  switch (property_id)
-    {
-    case PROP_STRING:
-      g_value_set_string (value, holder->string);
-      break;
-
-    default:
-      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
-      break;
-    }
-}
-
-static void
-gtk_drop_down_string_holder_class_init (GtkDropDownStringHolderClass *class)
-{
-  GObjectClass *object_class = G_OBJECT_CLASS (class);
-  GParamSpec *pspec;
-
-  object_class->finalize = gtk_drop_down_string_holder_finalize;
-  object_class->set_property = gtk_drop_down_string_holder_set_property;
-  object_class->get_property = gtk_drop_down_string_holder_get_property;
-
-  pspec = g_param_spec_string ("string", "String", "String",
-                               NULL,
-                               G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
-
-  g_object_class_install_property (object_class, PROP_STRING, pspec);
-
-}
-
-static GtkDropDownStringHolder *
-gtk_drop_down_string_holder_new (const char *string)
-{
-  return g_object_new (GTK_TYPE_DROP_DOWN_STRING_HOLDER, "string", string, NULL);
-}
-
-static GListModel *
-gtk_drop_down_strings_model_new (const char *const *text)
-{
-  GListStore *store;
-  int i;
-
-  store = g_list_store_new (GTK_TYPE_DROP_DOWN_STRING_HOLDER);
-  for (i = 0; text[i]; i++)
-    {
-      GtkDropDownStringHolder *holder = gtk_drop_down_string_holder_new (text[i]);
-      g_list_store_append (store, holder);
-      g_object_unref (holder);
-    }
-  return G_LIST_MODEL (store);
-}
-
 /**
  * gtk_drop_down_set_from_strings:
  * @self: a #GtkDropDown
@@ -1067,7 +936,6 @@ void
 gtk_drop_down_set_from_strings (GtkDropDown       *self,
                                 const char *const *texts)
 {
-  GtkExpression *expression;
   GListModel *model;
 
   g_return_if_fail (GTK_IS_DROP_DOWN (self));
@@ -1075,193 +943,7 @@ gtk_drop_down_set_from_strings (GtkDropDown       *self,
 
   set_default_factory (self);
 
-  expression = gtk_property_expression_new (GTK_TYPE_DROP_DOWN_STRING_HOLDER, NULL, "string");
-  gtk_drop_down_set_expression (self, expression);
-  gtk_expression_unref (expression);
-
-  model = gtk_drop_down_strings_model_new (texts);
+  model = G_LIST_MODEL (gtk_string_list_new ((const char **)texts));
   gtk_drop_down_set_model (self, model);
   g_object_unref (model);
 }
-
-typedef struct {
-  GtkBuilder    *builder;
-  GObject       *object;
-  const gchar   *domain;
-
-  gchar         *context;
-  guint          translatable : 1;
-  guint          is_text : 1;
-
-  GString       *string;
-  GPtrArray     *strings;
-} ItemParserData;
-
-static void
-item_start_element (GtkBuildableParseContext  *context,
-                    const gchar               *element_name,
-                    const gchar              **names,
-                    const gchar              **values,
-                    gpointer                   user_data,
-                    GError                   **error)
-{
-  ItemParserData *data = (ItemParserData*)user_data;
-
-  if (strcmp (element_name, "items") == 0)
-    {
-      if (!_gtk_builder_check_parent (data->builder, context, "object", error))
-        return;
-
-      if (!g_markup_collect_attributes (element_name, names, values, error,
-                                        G_MARKUP_COLLECT_INVALID, NULL, NULL,
-                                        G_MARKUP_COLLECT_INVALID))
-        _gtk_builder_prefix_error (data->builder, context, error);
-    }
-  else if (strcmp (element_name, "item") == 0)
-    {
-      gboolean translatable = FALSE;
-      const gchar *msg_context = NULL;
-
-      if (!_gtk_builder_check_parent (data->builder, context, "items", error))
-        return;
-
-      if (!g_markup_collect_attributes (element_name, names, values, error,
-                                        G_MARKUP_COLLECT_BOOLEAN|G_MARKUP_COLLECT_OPTIONAL, "translatable", &translatable,
-                                        G_MARKUP_COLLECT_STRING|G_MARKUP_COLLECT_OPTIONAL, "comments", NULL,
-                                        G_MARKUP_COLLECT_STRING|G_MARKUP_COLLECT_OPTIONAL, "context", &msg_context,
-                                        G_MARKUP_COLLECT_INVALID))
-        {
-          _gtk_builder_prefix_error (data->builder, context, error);
-          return;
-        }
-
-      data->is_text = TRUE;
-      data->translatable = translatable;
-      data->context = g_strdup (msg_context);
-    }
-  else
-    {
-      _gtk_builder_error_unhandled_tag (data->builder, context,
-                                        "GtkDropDown", element_name,
-                                        error);
-    }
-}
-
-static void
-item_text (GtkBuildableParseContext  *context,
-           const gchar               *text,
-           gsize                      text_len,
-           gpointer                   user_data,
-           GError                   **error)
-{
-  ItemParserData *data = (ItemParserData*)user_data;
-
-  if (data->is_text)
-    g_string_append_len (data->string, text, text_len);
-}
-
-static void
-item_end_element (GtkBuildableParseContext  *context,
-                  const gchar               *element_name,
-                  gpointer                   user_data,
-                  GError                   **error)
-{
-  ItemParserData *data = (ItemParserData*)user_data;
-
-  /* Append the translated strings */
-  if (data->string->len)
-    {
-      if (data->translatable)
-        {
-          const gchar *translated;
-
-          translated = _gtk_builder_parser_translate (data->domain,
-                                                      data->context,
-                                                      data->string->str);
-          g_string_assign (data->string, translated);
-        }
-
-      g_ptr_array_add (data->strings, g_strdup (data->string->str));
-    }
-
-  data->translatable = FALSE;
-  g_string_set_size (data->string, 0);
-  g_clear_pointer (&data->context, g_free);
-  data->is_text = FALSE;
-}
-
-static const GtkBuildableParser item_parser =
-{
-  item_start_element,
-  item_end_element,
-  item_text
-};
-
-static gboolean
-gtk_drop_down_buildable_custom_tag_start (GtkBuildable       *buildable,
-                                          GtkBuilder         *builder,
-                                          GObject            *child,
-                                          const gchar        *tagname,
-                                          GtkBuildableParser *parser,
-                                          gpointer           *parser_data)
-{
-  if (buildable_parent_iface->custom_tag_start (buildable, builder, child,
-                                                tagname, parser, parser_data))
-    return TRUE;
-
-  if (strcmp (tagname, "items") == 0)
-    {
-      ItemParserData *data;
-
-      data = g_slice_new0 (ItemParserData);
-      data->builder = g_object_ref (builder);
-      data->object = g_object_ref (G_OBJECT (buildable));
-      data->domain = gtk_builder_get_translation_domain (builder);
-      data->string = g_string_new ("");
-      data->strings = g_ptr_array_new_with_free_func (g_free);
-
-      *parser = item_parser;
-      *parser_data = data;
-
-      return TRUE;
-    }
-
-  return FALSE;
-}
-
-static void
-gtk_drop_down_buildable_custom_finished (GtkBuildable *buildable,
-                                         GtkBuilder   *builder,
-                                         GObject      *child,
-                                         const gchar  *tagname,
-                                         gpointer      user_data)
-{
-  ItemParserData *data;
-
-  buildable_parent_iface->custom_finished (buildable, builder, child,
-                                           tagname, user_data);
-
-  if (strcmp (tagname, "items") == 0)
-    {
-      data = (ItemParserData*)user_data;
-
-      g_ptr_array_add (data->strings, NULL);
-
-      gtk_drop_down_set_from_strings (GTK_DROP_DOWN (data->object), (const char **)data->strings->pdata);
-
-      g_object_unref (data->object);
-      g_object_unref (data->builder);
-      g_string_free (data->string, TRUE);
-      g_ptr_array_unref (data->strings);
-      g_slice_free (ItemParserData, data);
-    }
-}
-
-static void
-gtk_drop_down_buildable_interface_init (GtkBuildableIface *iface)
-{
-  buildable_parent_iface = g_type_interface_peek_parent (iface);
-
-  iface->custom_tag_start = gtk_drop_down_buildable_custom_tag_start;
-  iface->custom_finished = gtk_drop_down_buildable_custom_finished;
-}
diff --git a/gtk/gtkstringlist.c b/gtk/gtkstringlist.c
new file mode 100644
index 0000000000..d4cad21ad3
--- /dev/null
+++ b/gtk/gtkstringlist.c
@@ -0,0 +1,620 @@
+/*
+ * Copyright © 2020 Red Hat, Inc.
+ *
+ * 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 2.1 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/>.
+ *
+ * Authors: Matthias Clasen <mclasen@redhat.com>
+ */
+
+#include "config.h"
+
+#include "gtkstringlist.h"
+
+#include "gtkbuildable.h"
+#include "gtkbuilderprivate.h"
+#include "gtkintl.h"
+#include "gtkprivate.h"
+
+/**
+ * SECTION:gtkstringlist
+ * @title: GtkStringList
+ * @short_description: A list model for strings
+ * @see_also: #GListModel
+ *
+ * #GtkStringList is a list model that wraps an array of strings.
+ *
+ * The objects in the model have a "string" property.
+ *
+ * # GtkStringList as GtkBuildable
+ *
+ * The GtkStringList implementation of the GtkBuildable interface
+ * supports adding items directly using the <items> element and
+ * specifying <item> elements for each item. Each <item> element
+ * supports the regular translation attributes “translatable”,
+ * “context” and “comments”.
+ *
+ * Here is a UI definition fragment specifying a GtkStringList
+ * |[
+ * <object class="GtkStringList">
+ *   <items>
+ *     <item translatable="yes">Factory</item>
+ *     <item translatable="yes">Home</item>
+ *     <item translatable="yes">Subway</item>
+ *   </items>
+ * </object>
+ * ]|
+
+ */
+
+struct _GtkStringObject
+{
+  GObject parent_instance;
+  char *string;
+};
+
+enum {
+  PROP_STRING = 1,
+  PROP_NUM_PROPERTIES
+};
+
+G_DEFINE_TYPE (GtkStringObject, gtk_string_object, G_TYPE_OBJECT);
+
+static void
+gtk_string_object_init (GtkStringObject *object)
+{
+}
+
+static void
+gtk_string_object_finalize (GObject *object)
+{
+  GtkStringObject *self = GTK_STRING_OBJECT (object);
+
+  g_free (self->string);
+
+  G_OBJECT_CLASS (gtk_string_object_parent_class)->finalize (object);
+}
+
+static void
+gtk_string_object_set_property (GObject      *object,
+                                guint         property_id,
+                                const GValue *value,
+                                GParamSpec   *pspec)
+{
+  GtkStringObject *self = GTK_STRING_OBJECT (object);
+
+  switch (property_id)
+    {
+    case PROP_STRING:
+      g_free (self->string);
+      self->string = g_value_dup_string (value);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_string_object_get_property (GObject    *object,
+                                guint       property_id,
+                                GValue     *value,
+                                GParamSpec *pspec)
+{
+  GtkStringObject *self = GTK_STRING_OBJECT (object);
+
+  switch (property_id)
+    {
+    case PROP_STRING:
+      g_value_set_string (value, self->string);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+      break;
+    }
+}
+
+static void
+gtk_string_object_class_init (GtkStringObjectClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+  GParamSpec *pspec;
+
+  object_class->finalize = gtk_string_object_finalize;
+  object_class->set_property = gtk_string_object_set_property;
+  object_class->get_property = gtk_string_object_get_property;
+
+  pspec = g_param_spec_string ("string", "String", "String",
+                               NULL,
+                               G_PARAM_READWRITE |
+                               G_PARAM_CONSTRUCT_ONLY |
+                               G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_property (object_class, PROP_STRING, pspec);
+
+}
+
+static GtkStringObject *
+gtk_string_object_new (const char *string)
+{
+  return g_object_new (GTK_TYPE_STRING_OBJECT, "string", string, NULL);
+}
+
+static GtkStringObject *
+gtk_string_object_new_take (char *string)
+{
+  GtkStringObject *obj;
+
+  obj = g_object_new (GTK_TYPE_STRING_OBJECT, NULL);
+  obj->string = string;
+
+  return obj;
+}
+
+/**
+ * gtk_string_object_get_string:
+ * @self: a #GtkStringObject
+ *
+ * Returns the string contained in a #GtkStringObject.
+ *
+ * Returns: the string of @self
+ */
+const char *
+gtk_string_object_get_string (GtkStringObject *self)
+{
+  g_return_val_if_fail (GTK_IS_STRING_OBJECT (self), NULL);
+
+  return self->string;
+}
+
+struct _GtkStringList
+{
+  GObject parent_instance;
+
+  GSequence *items;
+};
+
+struct _GtkStringListClass
+{
+  GObjectClass parent_class;
+};
+
+static GType
+gtk_string_list_get_item_type (GListModel *list)
+{
+  return G_TYPE_OBJECT;
+}
+
+static guint
+gtk_string_list_get_n_items (GListModel *list)
+{
+  GtkStringList *self = GTK_STRING_LIST (list);
+
+  return g_sequence_get_length (self->items);
+}
+
+static gpointer
+gtk_string_list_get_item (GListModel *list,
+                          guint       position)
+{
+  GtkStringList *self = GTK_STRING_LIST (list);
+  GSequenceIter *iter;
+
+  iter = g_sequence_get_iter_at_pos (self->items, position);
+
+  if (g_sequence_iter_is_end (iter))
+    return NULL;
+  else
+    return g_object_ref (g_sequence_get (iter));
+}
+
+static void
+gtk_string_list_model_init (GListModelInterface *iface)
+{
+  iface->get_item_type = gtk_string_list_get_item_type;
+  iface->get_n_items = gtk_string_list_get_n_items;
+  iface->get_item = gtk_string_list_get_item;
+}
+
+typedef struct
+{
+  GtkBuilder    *builder;
+  GtkStringList *list;
+  GString       *string;
+  const gchar   *domain;
+  gchar         *context;
+
+  guint          translatable : 1;
+  guint          is_text      : 1;
+} ItemParserData;
+
+static void
+item_start_element (GtkBuildableParseContext  *context,
+                    const gchar               *element_name,
+                    const gchar              **names,
+                    const gchar              **values,
+                    gpointer                   user_data,
+                    GError                   **error)
+{
+  ItemParserData *data = (ItemParserData*)user_data;
+
+  if (strcmp (element_name, "items") == 0)
+    {
+      if (!_gtk_builder_check_parent (data->builder, context, "object", error))
+        return;
+
+      if (!g_markup_collect_attributes (element_name, names, values, error,
+                                        G_MARKUP_COLLECT_INVALID, NULL, NULL,
+                                        G_MARKUP_COLLECT_INVALID))
+        _gtk_builder_prefix_error (data->builder, context, error);
+    }
+  else if (strcmp (element_name, "item") == 0)
+    {
+      gboolean translatable = FALSE;
+      const gchar *msg_context = NULL;
+
+      if (!_gtk_builder_check_parent (data->builder, context, "items", error))
+        return;
+
+      if (!g_markup_collect_attributes (element_name, names, values, error,
+                                        G_MARKUP_COLLECT_BOOLEAN|G_MARKUP_COLLECT_OPTIONAL, "translatable", &translatable,
+                                        G_MARKUP_COLLECT_STRING|G_MARKUP_COLLECT_OPTIONAL, "comments", NULL,
+                                        G_MARKUP_COLLECT_STRING|G_MARKUP_COLLECT_OPTIONAL, "context", &msg_context,
+                                        G_MARKUP_COLLECT_INVALID))
+        {
+          _gtk_builder_prefix_error (data->builder, context, error);
+          return;
+        }
+
+      data->is_text = TRUE;
+      data->translatable = translatable;
+      data->context = g_strdup (msg_context);
+    }
+  else
+    {
+      _gtk_builder_error_unhandled_tag (data->builder, context,
+                                        "GtkStringList", element_name,
+                                        error);
+    }
+}
+
+static void
+item_text (GtkBuildableParseContext  *context,
+           const gchar               *text,
+           gsize                      text_len,
+           gpointer                   user_data,
+           GError                   **error)
+{
+  ItemParserData *data = (ItemParserData*)user_data;
+
+  if (data->is_text)
+    g_string_append_len (data->string, text, text_len);
+}
+
+static void
+item_end_element (GtkBuildableParseContext  *context,
+                  const gchar               *element_name,
+                  gpointer                   user_data,
+                  GError                   **error)
+{
+  ItemParserData *data = (ItemParserData*)user_data;
+
+  /* Append the translated strings */
+  if (data->string->len)
+    {
+      if (data->translatable)
+        {
+          const char *translated;
+
+          translated = _gtk_builder_parser_translate (data->domain,
+                                                      data->context,
+                                                      data->string->str);
+          g_string_assign (data->string, translated);
+        }
+
+      g_sequence_append (data->list->items, gtk_string_object_new (data->string->str));
+    }
+
+  data->translatable = FALSE;
+  g_string_set_size (data->string, 0);
+  g_clear_pointer (&data->context, g_free);
+  data->is_text = FALSE;
+}
+
+static const GtkBuildableParser item_parser =
+{
+  item_start_element,
+  item_end_element,
+  item_text
+};
+
+static gboolean
+gtk_string_list_buildable_custom_tag_start (GtkBuildable       *buildable,
+                                            GtkBuilder         *builder,
+                                            GObject            *child,
+                                            const gchar        *tagname,
+                                            GtkBuildableParser *parser,
+                                            gpointer           *parser_data)
+{
+  if (strcmp (tagname, "items") == 0)
+    {
+      ItemParserData *data;
+
+      data = g_slice_new0 (ItemParserData);
+      data->builder = g_object_ref (builder);
+      data->list = g_object_ref (GTK_STRING_LIST (buildable));
+      data->domain = gtk_builder_get_translation_domain (builder);
+      data->string = g_string_new ("");
+
+      *parser = item_parser;
+      *parser_data = data;
+
+      return TRUE;
+    }
+
+  return FALSE;
+}
+
+static void
+gtk_string_list_buildable_custom_finished (GtkBuildable *buildable,
+                                           GtkBuilder   *builder,
+                                           GObject      *child,
+                                           const gchar  *tagname,
+                                           gpointer      user_data)
+{
+  if (strcmp (tagname, "items") == 0)
+    {
+      ItemParserData *data;
+
+      data = (ItemParserData*)user_data;
+      g_object_unref (data->list);
+      g_object_unref (data->builder);
+      g_string_free (data->string, TRUE);
+      g_slice_free (ItemParserData, data);
+    }
+}
+
+static void
+gtk_string_list_buildable_init (GtkBuildableIface *iface)
+{
+  iface->custom_tag_start = gtk_string_list_buildable_custom_tag_start;
+  iface->custom_finished = gtk_string_list_buildable_custom_finished;
+}
+
+G_DEFINE_TYPE_WITH_CODE (GtkStringList, gtk_string_list, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (GTK_TYPE_BUILDABLE,
+                                                gtk_string_list_buildable_init)
+                         G_IMPLEMENT_INTERFACE (G_TYPE_LIST_MODEL,
+                                                gtk_string_list_model_init))
+
+static void
+gtk_string_list_dispose (GObject *object)
+{
+  GtkStringList *self = GTK_STRING_LIST (object);
+
+  g_clear_pointer (&self->items, g_sequence_free);
+
+  G_OBJECT_CLASS (gtk_string_list_parent_class)->dispose (object);
+}
+
+static void
+gtk_string_list_class_init (GtkStringListClass *class)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (class);
+
+  gobject_class->dispose = gtk_string_list_dispose;
+}
+
+static void
+gtk_string_list_init (GtkStringList *self)
+{
+  self->items = g_sequence_new (g_object_unref);
+}
+
+/**
+ * gtk_string_list_new:
+ * @strings: (allow-none): The strings to put in the model
+ *
+ * Creates a new #GtkStringList with the given @strings.
+ *
+ * Returns: a new #GtkStringList
+ **/
+GtkStringList *
+gtk_string_list_new (const char **strings)
+{
+  GtkStringList *self;
+  guint i;
+
+  self = g_object_new (GTK_TYPE_STRING_LIST, NULL);
+
+  for (i = 0; strings[i]; i++)
+    g_sequence_append (self->items, gtk_string_object_new (strings[i]));
+
+  return self;
+}
+
+/**
+ * gtk_string_list_splice:
+ * @self: a #GtkStringList
+ * @position: the position at which to make the change
+ * @n_removals: the number of strings to remove
+ * @additions: (array length=n_additions): the strings to add
+ * @n_additions: the number of items to add
+ *
+ * Changes @self by removing @n_removals strings and adding @n_additions
+ * strings to it.
+ *
+ * This function is more efficient than gtk_string_list_insert() and
+ * gtk_string_list_remove(), because it only emits
+ * #GListModel::items-changed once for the change.
+ *
+ * This function takes a ref on each item in @additions.
+ *
+ * The parameters @position and @n_removals must be correct (ie:
+ * @position + @n_removals must be less than or equal to the length
+ * of the list at the time this function is called).
+ */
+void
+gtk_string_list_splice (GtkStringList  *self,
+                        guint           position,
+                        guint           n_removals,
+                        const char    **additions,
+                        guint           n_additions)
+{
+  GSequenceIter *it;
+  guint n_items;
+
+  g_return_if_fail (GTK_IS_STRING_LIST (self));
+  g_return_if_fail (position + n_removals >= position); /* overflow */
+
+  n_items = g_sequence_get_length (self->items);
+  g_return_if_fail (position + n_removals <= n_items);
+
+  it = g_sequence_get_iter_at_pos (self->items, position);
+
+  if (n_removals)
+    {
+      GSequenceIter *end;
+
+      end = g_sequence_iter_move (it, n_removals);
+      g_sequence_remove_range (it, end);
+
+      it = end;
+    }
+
+  if (n_additions)
+    {
+      gint i;
+
+      for (i = 0; i < n_additions; i++)
+        {
+          g_sequence_insert_before (it, gtk_string_object_new (additions[i]));
+        }
+    }
+
+  g_list_model_items_changed (G_LIST_MODEL (self), position, n_removals, n_additions);
+}
+
+/**
+ * gtk_string_list_append:
+ * @self: a #GtkStringList
+ * @string: the string to insert
+ *
+ * Appends @string to @self.
+ *
+ * The @string will be copied. See gtk_string_list_take()
+ * for a way to avoid that.
+ */
+void
+gtk_string_list_append (GtkStringList *self,
+                        const char    *string)
+{
+  guint n_items;
+
+  g_return_if_fail (GTK_IS_STRING_LIST (self));
+
+  n_items = g_sequence_get_length (self->items);
+  g_sequence_append (self->items, gtk_string_object_new (string));
+
+  g_list_model_items_changed (G_LIST_MODEL (self), n_items, 0, 1);
+}
+
+/**
+ * gtk_string_list_take:
+ * @self: a #GtkStringList
+ * @string: the string to insert
+ *
+ * Adds @string to self at the end, and takes
+ * ownership of it.
+ *
+ * This variant of gtk_string_list_append() is
+ * convenient for formatting strings:
+ *
+ * |[
+ * gtk_string_list_take (self, g_strdup_print ("%d dollars", lots));
+ * ]|
+ */
+void
+gtk_string_list_take (GtkStringList *self,
+                      char          *string)
+{
+  guint n_items;
+
+  g_return_if_fail (GTK_IS_STRING_LIST (self));
+
+  n_items = g_sequence_get_length (self->items);
+  g_sequence_append (self->items, gtk_string_object_new_take (string));
+
+  g_list_model_items_changed (G_LIST_MODEL (self), n_items, 0, 1);
+}
+
+/**
+ * gtk_string_list_remove:
+ * @self: a #GtkStringList
+ * @position: the position of the string that is to be removed
+ *
+ * Removes the string at @position from @self. @position must
+ * be smaller than the current length of the list.
+ */
+void
+gtk_string_list_remove (GtkStringList *self,
+                        guint          position)
+{
+  GSequenceIter *iter;
+
+  g_return_if_fail (GTK_IS_STRING_LIST (self));
+
+  iter = g_sequence_get_iter_at_pos (self->items, position);
+  g_return_if_fail (!g_sequence_iter_is_end (iter));
+
+  g_sequence_remove (iter);
+
+  g_list_model_items_changed (G_LIST_MODEL (self), position, 1, 0);
+}
+
+/**
+ * gtk_string_list_get_string:
+ * @self: a #GtkStringList
+ * @position:
+ *
+ * Gets the string that is at @position in @self. @position
+ * must be smaller than the current length of the list.
+ *
+ * This function returns the const char *. To get the
+ * object wrapping it, use g_list_model_get_item().
+ *
+ * Returns: the string at the given position
+ */
+const char *
+gtk_string_list_get_string (GtkStringList *self,
+                            guint          position)
+{
+  GSequenceIter *iter;
+
+  g_return_val_if_fail (GTK_IS_STRING_LIST (self), NULL);
+
+  iter = g_sequence_get_iter_at_pos (self->items, position);
+
+  if (g_sequence_iter_is_end (iter))
+    {
+      return NULL;
+    }
+  else
+    {
+      GtkStringObject *obj = g_sequence_get (iter);
+
+      return obj->string;
+    }
+}
diff --git a/gtk/gtkstringlist.h b/gtk/gtkstringlist.h
new file mode 100644
index 0000000000..31c788312a
--- /dev/null
+++ b/gtk/gtkstringlist.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright © 2020 Red Hat, Inc.
+ *
+ * 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 2.1 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/>.
+ *
+ * Authors: Matthias Clasen <mclasen@redhat.com>
+ */
+
+#ifndef __GTK_STRING_LIST_H__
+#define __GTK_STRING_LIST_H__
+
+
+#if !defined (__GTK_H_INSIDE__) && !defined (GTK_COMPILATION)
+#error "Only <gtk/gtk.h> can be included directly."
+#endif
+
+#include <gio/gio.h>
+/* for GDK_AVAILABLE_IN_ALL */
+#include <gdk/gdk.h>
+
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_STRING_OBJECT (gtk_string_object_get_type ())
+GDK_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (GtkStringObject, gtk_string_object, GTK, STRING_OBJECT, GObject)
+
+GDK_AVAILABLE_IN_ALL
+const char *         gtk_string_object_get_string (GtkStringObject *self);
+
+#define GTK_TYPE_STRING_LIST (gtk_string_list_get_type ())
+
+GDK_AVAILABLE_IN_ALL
+G_DECLARE_FINAL_TYPE (GtkStringList, gtk_string_list, GTK, STRING_LIST, GObject)
+
+GDK_AVAILABLE_IN_ALL
+GtkStringList * gtk_string_list_new             (const char **strings);
+
+GDK_AVAILABLE_IN_ALL
+void            gtk_string_list_append          (GtkStringList *self,
+                                                 const char    *string);
+
+GDK_AVAILABLE_IN_ALL
+void            gtk_string_list_take            (GtkStringList *self,
+                                                 char          *string);
+
+GDK_AVAILABLE_IN_ALL
+void            gtk_string_list_remove          (GtkStringList *self,
+                                                 guint          position);
+
+GDK_AVAILABLE_IN_ALL
+void            gtk_string_list_splice          (GtkStringList  *self,
+                                                 guint           position,
+                                                 guint           n_removals,
+                                                 const char    **additions,
+                                                 guint           n_additions);
+
+GDK_AVAILABLE_IN_ALL
+const char *    gtk_string_list_get_string      (GtkStringList *self,
+                                                 guint          position);
+
+G_END_DECLS
+
+#endif /* __GTK_STRING_LIST_H__ */
diff --git a/gtk/meson.build b/gtk/meson.build
index 83048902a7..ac11bf9cb2 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -380,6 +380,7 @@ gtk_public_sources = files([
   'gtkstackswitcher.c',
   'gtkstatusbar.c',
   'gtkstringfilter.c',
+  'gtkstringlist.c',
   'gtkstringsorter.c',
   'gtkstylecontext.c',
   'gtkstyleprovider.c',
diff --git a/gtk/ui/gtkprintunixdialog.ui b/gtk/ui/gtkprintunixdialog.ui
index 2910e526ea..6d086c9da8 100644
--- a/gtk/ui/gtkprintunixdialog.ui
+++ b/gtk/ui/gtkprintunixdialog.ui
@@ -511,11 +511,15 @@
                                       <object class="GtkDropDown" id="page_set_combo">
                                         <property name="valign">baseline</property>
                                         <property name="selected">0</property>
-                                        <items>
-                                          <item translatable="yes">All sheets</item>
-                                          <item translatable="yes">Even sheets</item>
-                                          <item translatable="yes">Odd sheets</item>
-                                        </items>
+                                        <property name="model">
+                                          <object class="GtkStringList">
+                                            <items>
+                                              <item translatable="yes">All sheets</item>
+                                              <item translatable="yes">Even sheets</item>
+                                              <item translatable="yes">Odd sheets</item>
+                                            </items>
+                                          </object>
+                                        </property>
                                         <layout>
                                           <property name="left-attach">1</property>
                                           <property name="top-attach">3</property>
@@ -695,12 +699,16 @@
                                         <property name="sensitive">0</property>
                                         <property name="selected">0</property>
                                         <property name="valign">baseline</property>
-                                        <items>
-                                          <item translatable="yes">Portrait</item>
-                                          <item translatable="yes">Landscape</item>
-                                          <item translatable="yes">Reverse portrait</item>
-                                          <item translatable="yes">Reverse landscape</item>
-                                        </items>
+                                        <property name="model">
+                                          <object class="GtkStringList">
+                                            <items>
+                                              <item translatable="yes">Portrait</item>
+                                              <item translatable="yes">Landscape</item>
+                                              <item translatable="yes">Reverse portrait</item>
+                                              <item translatable="yes">Reverse landscape</item>
+                                            </items>
+                                          </object>
+                                        </property>
                                         <layout>
                                           <property name="left-attach">1</property>
                                           <property name="top-attach">4</property>