gtk3-demo: Add a markup demo

demos/gtk-demo/Makefile.am

@@ -39,6 +39,7 @@ demos_base =					\
 	listbox.c				\
 	flowbox.c				\
 	list_store.c				\
+	markup.c				\
 	menus.c					\
 	offscreen_window.c			\
 	offscreen_window2.c			\

demos/gtk-demo/demo.gresource.xml

@@ -145,6 +145,7 @@
     <file>links.c</file>
     <file>listbox.c</file>
     <file>list_store.c</file>
+    <file>markup.c</file>
     <file>menus.c</file>
     <file>offscreen_window.c</file>
     <file>offscreen_window2.c</file>
@@ -201,4 +202,7 @@
     <file>decor1.png</file>
     <file>decor2.png</file>
   </gresource>
+  <gresource prefix="/markup">
+    <file>markup.txt</file>
+  </gresource>
 </gresources>

demos/gtk-demo/markup.c

@@ -0,0 +1,64 @@
+/* Text Widget/Markup
+ *
+ * GtkTextBuffer lets you define your own tags that can influence
+ * text formatting in a variety of ways. In this example, we show
+ * that GtkTextBuffer can load Pango markup and automatically generate
+ * suitable tags.
+ */
+
+#include <gtk/gtk.h>
+
+GtkWidget *
+do_markup (GtkWidget *do_widget)
+{
+  static GtkWidget *window = NULL;
+
+  if (!window)
+    {
+      GtkWidget *view;
+      GtkWidget *sw;
+      GtkTextBuffer *buffer;
+      GtkTextIter iter;
+      GBytes *bytes;
+      const gchar *markup;
+
+      window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+      gtk_window_set_screen (GTK_WINDOW (window),
+                             gtk_widget_get_screen (do_widget));
+      gtk_window_set_default_size (GTK_WINDOW (window), 450, 400);
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (gtk_widget_destroyed), &window);
+
+      gtk_window_set_title (GTK_WINDOW (window), "Markup");
+
+      view = gtk_text_view_new ();
+      gtk_text_view_set_wrap_mode (GTK_TEXT_VIEW (view), GTK_WRAP_WORD);
+      gtk_text_view_set_left_margin (GTK_TEXT_VIEW (view), 10);
+      gtk_text_view_set_right_margin (GTK_TEXT_VIEW (view), 10);
+
+      sw = gtk_scrolled_window_new (NULL, NULL);
+      gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
+                                      GTK_POLICY_NEVER,
+                                      GTK_POLICY_AUTOMATIC);
+      gtk_container_add (GTK_CONTAINER (window), sw);
+      gtk_container_add (GTK_CONTAINER (sw), view);
+
+      bytes = g_resources_lookup_data ("/markup/markup.txt", 0, NULL);
+      markup = (const gchar *)g_bytes_get_data (bytes, NULL);
+
+      buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
+      gtk_text_buffer_get_start_iter (buffer, &iter);
+      gtk_text_buffer_insert_markup (buffer, &iter, markup, -1);
+
+      g_bytes_unref (bytes);
+
+      gtk_widget_show_all (sw);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show (window);
+  else
+    gtk_widget_destroy (window);
+
+  return window;
+}

demos/gtk-demo/markup.txt

@@ -0,0 +1,14 @@
+
+Text sizes: <span size="xx-small">tiny</span> <span size="x-small">very small</span> <span size="small">small</span> <span size="medium">normal</span> <span size="large">large</span> <span size="x-large">very large</span> <span size="xx-large">huge</span>
+
+Colorful <span underline="low" underline-color="blue"><span underline="double" underline-color="red">under</span>lines</span>
+
+Colorful <span strikethrough="true" strikethrough-color="magenta">strikethroughs</span>
+
+Text <span color="gray">c<span color="green">o</span>l<span color="tomato">o</span>rs</span>
+
+More superscripts: 2<span rise="8000" size="smaller">2<span rise="14000" size="smaller">2</span></span>
+
+<span letter_spacing="3000">Letterspacing</span>
+
+Shortcuts: <tt>Monospace</tt> – <b>Bold</b> – <i>Italic</i> – <big>Big</big> – <small>Small</small> – <u>Underlined</u> – <s>Strikethrough</s> – Super<sup>script</sup> – Sub<sub>script</sub>