Add foreigndrawing example to gtk3-demo

This makes it easier accessible and nicer to refer to
from the documentation.

demos/gtk-demo/Makefile.am

@@ -27,6 +27,7 @@ demos_base =					\
 	expander.c  				\
         filtermodel.c				\
 	font_features.c				\
+	foreigndrawing.c			\
 	gestures.c				\
 	glarea.c				\
 	headerbar.c				\

demos/gtk-demo/demo.gresource.xml

@@ -140,6 +140,7 @@
     <file>expander.c</file>
     <file>filtermodel.c</file>
     <file>flowbox.c</file>
+    <file>foreigndrawing.c</file>
     <file>font_features.c</file>
     <file>gestures.c</file>
     <file>glarea.c</file>

demos/gtk-demo/foreigndrawing.c

@@ -1,23 +1,15 @@
-/* foreign-drawing.c
+/* Foreign drawing
- * Copyright (C) 2015 Red Hat, Inc
- * Author: Matthias Clasen
  *
- * This library is free software; you can redistribute it and/or
+ * Many applications can't use GTK+ widgets, for a variety of reasons,
- * modify it under the terms of the GNU Library General Public
+ * but still want their user interface to appear integrated with the
- * License as published by the Free Software Foundation; either
+ * rest of the desktop, and follow GTK+ themes.
- * version 2 of the License, or (at your option) any later version.
  *
- * This library is distributed in the hope that it will be useful,
+ * This demo shows how to use GtkStyleContext and the gtk_render_ APIs
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * to achieve this. Note that this is a very simple, non-interactive
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * example.
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this library. If not, see <http://www.gnu.org/licenses/>.
  */
 
 #include <gtk/gtk.h>
-
 #include <string.h>
 
 static void
@@ -133,8 +125,6 @@ get_style (GtkStyleContext *parent,
   context = gtk_style_context_new ();
   gtk_style_context_set_path (context, path);
   gtk_style_context_set_parent (context, parent);
-  /* XXX: Why is this necessary? */
-  gtk_style_context_set_state (context, gtk_widget_path_iter_get_state (path, -1));
   gtk_widget_path_unref (path);
 
   return context;
@@ -309,16 +299,23 @@ draw_cb (GtkWidget *widget,
   return FALSE;
 }
 
-int
+GtkWidget *
-main (int argc, char *argv[])
+do_foreigndrawing (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
     {
-  GtkWidget *window;
       GtkWidget *box;
       GtkWidget *da;
 
-  gtk_init (NULL, NULL);
-
       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+      gtk_window_set_title (GTK_WINDOW (window), "Foreign drawing");
+      gtk_window_set_screen (GTK_WINDOW (window),
+                             gtk_widget_get_screen (do_widget));
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (gtk_widget_destroyed), &window);
+
       box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 10);
       gtk_container_add (GTK_CONTAINER (window), box);
       da = gtk_drawing_area_new ();
@@ -329,10 +326,12 @@ main (int argc, char *argv[])
       gtk_container_add (GTK_CONTAINER (box), da);
 
       g_signal_connect (da, "draw", G_CALLBACK (draw_cb), NULL);
-
+    }
-  gtk_widget_show_all (window);
+
-
+  if (!gtk_widget_get_visible (window))
-  gtk_main ();
+    gtk_widget_show_all (window);
-
+  else
-  return 0;
+    gtk_widget_destroy (window);
+
+  return window;
 }

tests/Makefile.am

@@ -169,7 +169,6 @@ noinst_PROGRAMS =  $(TEST_PROGS)	\
 	testpopover			\
 	gdkgears			\
 	listmodel			\
-	foreigndrawing			\
 	testpopup			\
 	$(NULL)