[gtk/wip/otte/json: 7/14] demos: Add a simple JSON demo

[Benjamin Otte <otte src gnome org>]

commit d3164ca10541bbebdf40207d57a0d38af2fecb95
Author: Benjamin Otte <otte redhat com>
Date:   Mon Nov 29 09:46:49 2021 +0100

    demos: Add a simple JSON demo
    
    Download the GTK releases from the gitlab REST API and display them in a
    list.
    
    Much creative.

 demos/gtk-demo/demo.gresource.xml  |   1 +
 demos/gtk-demo/listview_releases.c | 193 +++++++++++++++++++++++++++++++++++++
 demos/gtk-demo/meson.build         |   4 +-
 3 files changed, 197 insertions(+), 1 deletion(-)
---
diff --git a/demos/gtk-demo/demo.gresource.xml b/demos/gtk-demo/demo.gresource.xml
index 83e798fd25..804d79793a 100644
--- a/demos/gtk-demo/demo.gresource.xml
+++ b/demos/gtk-demo/demo.gresource.xml
@@ -304,6 +304,7 @@
     <file>listview_clocks.c</file>
     <file>listview_filebrowser.c</file>
     <file>listview_minesweeper.c</file>
+    <file>listview_releases.c</file>
     <file>listview_settings.c</file>
     <file>listview_ucd.c</file>
     <file>listview_weather.c</file>
diff --git a/demos/gtk-demo/listview_releases.c b/demos/gtk-demo/listview_releases.c
new file mode 100644
index 0000000000..a921b940ff
--- /dev/null
+++ b/demos/gtk-demo/listview_releases.c
@@ -0,0 +1,193 @@
+/* Lists/Application launcher
+ * #Keywords: GtkListItemFactory, GListModel,JSON
+ *
+ * This demo downloads GTK's latest release and displays them in a list.
+ *
+ * It shows how hard it still is to get JSON into lists.
+ */
+
+#include <gtk/gtk.h>
+
+#include "gtk/json/gtkjsonparserprivate.h"
+
+#define GTK_TYPE_RELEASE (gtk_release_get_type ())
+
+G_DECLARE_FINAL_TYPE (GtkRelease, gtk_release, GTK, RELEASE, GObject)
+
+struct _GtkRelease
+{
+  GObject parent_instance;
+
+  char *name;
+  GDateTime *timestamp;
+};
+
+struct _GtkReleaseClass
+{
+  GObjectClass parent_class;
+};
+
+G_DEFINE_TYPE (GtkRelease, gtk_release, G_TYPE_OBJECT)
+
+static void
+gtk_release_class_init (GtkReleaseClass *klass)
+{
+}
+
+static void
+gtk_release_init (GtkRelease *self)
+{
+}
+
+static GtkRelease *
+gtk_release_new (const char *name,
+                 GDateTime  *timestamp)
+{
+  GtkRelease *result;
+
+  result = g_object_new (GTK_TYPE_RELEASE, NULL);
+
+  result->name = g_strdup (name);
+
+  return result;
+}
+
+static void
+setup_listitem_cb (GtkListItemFactory *factory,
+                   GtkListItem        *list_item)
+{
+  GtkWidget *label;
+
+  label = gtk_label_new ("");
+  gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+  gtk_list_item_set_child (list_item, label);
+}
+
+static void
+bind_listitem_cb (GtkListItemFactory *factory,
+                  GtkListItem        *list_item)
+{
+  GtkWidget *label;
+  GtkRelease *release;
+
+  label = gtk_list_item_get_child (list_item);
+  release = gtk_list_item_get_item (list_item);
+
+  gtk_label_set_label (GTK_LABEL (label), release->name);
+}
+
+static void
+loaded_some_releases_cb (GObject      *file,
+                         GAsyncResult *res,
+                         gpointer      userdata)
+{
+  GListStore *store = userdata;
+  GBytes *bytes;
+  GtkJsonParser *parser;
+  GError *error = NULL;
+
+  bytes = g_file_load_bytes_finish (G_FILE (file), res, NULL, &error);
+  if (bytes == NULL)
+    {
+      g_printerr ("Error loading: %s\n", error->message);
+      g_clear_error (&error);
+      return;
+    }
+
+  parser = gtk_json_parser_new_for_bytes (bytes);
+  g_bytes_unref (bytes);
+
+  gtk_json_parser_start_array (parser);
+  do
+    {
+      enum { NAME, COMMIT };
+      static const char *options[] = { "name", "commit", NULL };
+      char *name = NULL;
+
+      gtk_json_parser_start_object (parser);
+      do
+        {
+          switch (gtk_json_parser_select_member (parser, options))
+            {
+              case NAME:
+                g_clear_pointer (&name, g_free);
+                name = gtk_json_parser_get_string (parser);
+                break;
+              case COMMIT:
+                break;
+              default:
+                break;
+            }
+        }
+      while (gtk_json_parser_next (parser));
+      gtk_json_parser_end (parser);
+
+      if (name)
+        {
+          GtkRelease *release = gtk_release_new (name, NULL);
+          g_list_store_append (store, release);
+          g_object_unref (release);
+        }
+      g_clear_pointer (&name, g_free);
+    }
+  while (gtk_json_parser_next (parser));
+  gtk_json_parser_end (parser);
+
+  if (gtk_json_parser_get_error (parser))
+    {
+      const GError *json_error = gtk_json_parser_get_error (parser);
+
+      g_printerr ("Error parsing: %s\n", json_error->message);
+    }
+  gtk_json_parser_free (parser);
+}
+
+static void
+load_some_releases (GListStore *store)
+{
+  GFile *file = g_file_new_for_uri ("https://gitlab.gnome.org/api/v4/projects/665/repository/tags";);
+
+  g_file_load_bytes_async (file, NULL, loaded_some_releases_cb, store);
+  g_object_unref (file);
+}
+
+static GtkWidget *window = NULL;
+
+GtkWidget *
+do_listview_releases (GtkWidget *do_widget)
+{
+  if (window == NULL)
+    {
+      GtkWidget *list, *sw;
+      GListStore *store;
+      GtkListItemFactory *factory;
+
+      window = gtk_window_new ();
+      gtk_window_set_default_size (GTK_WINDOW (window), 640, 320);
+      gtk_window_set_display (GTK_WINDOW (window),
+                              gtk_widget_get_display (do_widget));
+      gtk_window_set_title (GTK_WINDOW (window), "GTK releases");
+      g_object_add_weak_pointer (G_OBJECT (window), (gpointer *) &window);
+
+      factory = gtk_signal_list_item_factory_new ();
+      g_signal_connect (factory, "setup", G_CALLBACK (setup_listitem_cb), NULL);
+      g_signal_connect (factory, "bind", G_CALLBACK (bind_listitem_cb), NULL);
+
+      store = g_list_store_new (GTK_TYPE_RELEASE);
+
+      list = gtk_list_view_new (GTK_SELECTION_MODEL (gtk_single_selection_new (G_LIST_MODEL (store))), 
factory);
+
+      sw = gtk_scrolled_window_new ();
+      gtk_window_set_child (GTK_WINDOW (window), sw);
+      gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (sw), list);
+
+      load_some_releases (store);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_window_destroy (GTK_WINDOW (window));
+
+  return window;
+}
diff --git a/demos/gtk-demo/meson.build b/demos/gtk-demo/meson.build
index 3576399f04..4328643373 100644
--- a/demos/gtk-demo/meson.build
+++ b/demos/gtk-demo/meson.build
@@ -55,6 +55,7 @@ demos = files([
   'listview_filebrowser.c',
   'listview_minesweeper.c',
   'dropdown.c',
+  'listview_releases.c',
   'listview_settings.c',
   'listview_ucd.c',
   'listview_weather.c',
@@ -100,7 +101,7 @@ demos = files([
   'video_player.c',
 ])
 
-gtkdemo_deps = [ libgtk_dep, ]
+gtkdemo_deps = [ libgtk_dep, libgtk_json_dep ]
 
 extra_demo_sources = files([
   'main.c',
@@ -244,6 +245,7 @@ executable('gtk4-demo',
   include_directories: confinc,
   gui_app: true,
   link_args: extra_demo_ldflags,
+  link_with: [ libgtk_json, ],
   install: true,
 )