[libchamplain] Add demo of the new overlay sources

[Jiří Techet <jiritechet src gnome org>]

commit 3adb78f718e63aeb3ca5c15b59c1469f8cbc9e12
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Fri Aug 16 22:16:54 2013 +0200

    Add demo of the new overlay sources
    
    Allow to add overlay sources in the demo app.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=704645

 demos/launcher-gtk.c |   62 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 61 insertions(+), 1 deletions(-)
---
diff --git a/demos/launcher-gtk.c b/demos/launcher-gtk.c
index 730f237..80fbdcd 100644
--- a/demos/launcher-gtk.c
+++ b/demos/launcher-gtk.c
@@ -210,13 +210,65 @@ append_point (ChamplainPathLayer *layer, gdouble lon, gdouble lat)
   champlain_path_layer_add_node (layer, CHAMPLAIN_LOCATION (coord));
 }
 
+static void
+add_clicked (GtkButton     *button,
+             ChamplainView *view)
+{
+  GtkWidget *window, *dialog, *vbox, *combo;
+  GtkResponseType response;
+
+  window = g_object_get_data (G_OBJECT (view), "window");
+  dialog = gtk_dialog_new_with_buttons ("Add secondary map source",
+                                        GTK_WINDOW (window),
+                                        GTK_DIALOG_MODAL,
+                                        "Add",
+                                        GTK_RESPONSE_OK,
+                                        "Cancel",
+                                        GTK_RESPONSE_CANCEL,
+                                        NULL);
+
+  combo = gtk_combo_box_new ();
+  build_combo_box (GTK_COMBO_BOX (combo));
+  gtk_combo_box_set_active (GTK_COMBO_BOX (combo), 0);
+
+  vbox = gtk_dialog_get_content_area (GTK_DIALOG (dialog));
+  gtk_container_add (GTK_CONTAINER (vbox), combo);
+
+  gtk_widget_show_all (dialog);
+
+  response = gtk_dialog_run (GTK_DIALOG (dialog));
+
+  if (response == GTK_RESPONSE_OK) {
+    GtkTreeModel *model;
+    GtkTreeIter iter;
+    ChamplainMapSource *source;
+    ChamplainMapSourceFactory *factory;
+    char *id;
+
+    if (!gtk_combo_box_get_active_iter (GTK_COMBO_BOX (combo), &iter))
+      return;
+
+    model = gtk_combo_box_get_model (GTK_COMBO_BOX (combo));
+
+    gtk_tree_model_get (model, &iter, COL_ID, &id, -1);
+
+    factory = champlain_map_source_factory_dup_default ();
+    source = champlain_map_source_factory_create_memcached_source (factory, id);
+
+    champlain_view_add_overlay_source (view, source, 0.6 * 255);
+    g_object_unref (factory);
+    g_free (id);
+  }
+
+  gtk_widget_destroy (dialog);
+}
 
 int
 main (int argc,
     char *argv[])
 {
   GtkWidget *window;
-  GtkWidget *widget, *vbox, *bbox, *button, *viewport;
+  GtkWidget *widget, *vbox, *bbox, *button, *image, *viewport;
   ChamplainView *view;
   ChamplainMarkerLayer *layer;
   ClutterActor *scale;
@@ -253,6 +305,8 @@ main (int argc,
       "kinetic-mode", TRUE,
       "zoom-level", 5,
       NULL);
+
+  g_object_set_data (G_OBJECT (view), "window", window);
       
   scale = champlain_scale_new ();
   champlain_scale_connect_view (CHAMPLAIN_SCALE (scale), view);
@@ -316,6 +370,12 @@ main (int argc,
       button);
   gtk_container_add (GTK_CONTAINER (bbox), button);
 
+  button = gtk_button_new ();
+  image = gtk_image_new_from_icon_name ("list-add-symbolic", GTK_ICON_SIZE_LARGE_TOOLBAR);
+  gtk_container_add (GTK_CONTAINER (button), image);
+  g_signal_connect (button, "clicked", G_CALLBACK (add_clicked), view);
+  gtk_container_add (GTK_CONTAINER (bbox), button);
+
   button = gtk_image_new ();
   gtk_widget_set_size_request (button, 22, -1);
   g_signal_connect (view, "notify::state", G_CALLBACK (view_state_changed),