[gtk+] gtk-demo: Add a CSS shadows demo

[Benjamin Otte <otte src gnome org>]

commit c6a78d76bd6b361cd23e8d78f564358e51c50e0d
Author: Benjamin Otte <otte redhat com>
Date:   Fri Sep 21 18:50:15 2012 +0200

    gtk-demo: Add a CSS shadows demo

 demos/gtk-demo/Makefile.am        |    2 +
 demos/gtk-demo/css_shadows.c      |  147 +++++++++++++++++++++++++++++++++++++
 demos/gtk-demo/css_shadows.css    |   44 +++++++++++
 demos/gtk-demo/demo.gresource.xml |    3 +
 4 files changed, 196 insertions(+), 0 deletions(-)
---
diff --git a/demos/gtk-demo/Makefile.am b/demos/gtk-demo/Makefile.am
index 1b7fa05..afdda22 100644
--- a/demos/gtk-demo/Makefile.am
+++ b/demos/gtk-demo/Makefile.am
@@ -19,6 +19,7 @@ demos =						\
 	css_basics.c				\
 	css_multiplebgs.c			\
 	css_pixbufs.c				\
+	css_shadows.c				\
 	dialog.c				\
 	drawingarea.c				\
 	editable_cells.c			\
@@ -120,6 +121,7 @@ RESOURCES=	application.ui			\
 		css_basics.css			\
 		css_multiplebgs.css		\
 		css_pixbufs.css			\
+		css_shadows.css			\
 		cssview.css			\
 		fancy.css			\
 		reset.css
diff --git a/demos/gtk-demo/css_shadows.c b/demos/gtk-demo/css_shadows.c
new file mode 100644
index 0000000..382d558
--- /dev/null
+++ b/demos/gtk-demo/css_shadows.c
@@ -0,0 +1,147 @@
+/* CSS Theming/Shadows
+ *
+ * This demo shows how to use CSS shadows.
+ */
+
+#include <gtk/gtk.h>
+
+static GtkWidget *window = NULL;
+
+static void
+show_parsing_error (GtkCssProvider *provider,
+                    GtkCssSection  *section,
+                    const GError   *error,
+                    GtkTextBuffer  *buffer)
+{
+  GtkTextIter start, end;
+  const char *tag_name;
+
+  gtk_text_buffer_get_iter_at_line_index (buffer,
+                                          &start,
+                                          gtk_css_section_get_start_line (section),
+                                          gtk_css_section_get_start_position (section));
+  gtk_text_buffer_get_iter_at_line_index (buffer,
+                                          &end,
+                                          gtk_css_section_get_end_line (section),
+                                          gtk_css_section_get_end_position (section));
+
+  if (g_error_matches (error, GTK_CSS_PROVIDER_ERROR, GTK_CSS_PROVIDER_ERROR_DEPRECATED))
+    tag_name = "warning";
+  else
+    tag_name = "error";
+
+  gtk_text_buffer_apply_tag_by_name (buffer, tag_name, &start, &end);
+}
+                    
+static void
+css_text_changed (GtkTextBuffer  *buffer,
+                  GtkCssProvider *provider)
+{
+  GtkTextIter start, end;
+  char *text;
+
+  gtk_text_buffer_get_start_iter (buffer, &start);
+  gtk_text_buffer_get_end_iter (buffer, &end);
+  gtk_text_buffer_remove_all_tags (buffer, &start, &end);
+
+  text = gtk_text_buffer_get_text (buffer, &start, &end, FALSE);
+  gtk_css_provider_load_from_data (provider, text, -1, NULL);
+  g_free (text);
+
+  gtk_style_context_reset_widgets (gdk_screen_get_default ());
+}
+
+static void
+apply_css (GtkWidget *widget, GtkStyleProvider *provider)
+{
+  gtk_style_context_add_provider (gtk_widget_get_style_context (widget), provider, G_MAXUINT);
+  if (GTK_IS_CONTAINER (widget))
+    gtk_container_forall (GTK_CONTAINER (widget), (GtkCallback) apply_css, provider);
+}
+
+GtkWidget *
+create_toolbar (void)
+{
+  GtkWidget *toolbar;
+  GtkToolItem *item;
+
+  toolbar = gtk_toolbar_new ();
+  gtk_widget_set_valign (toolbar, GTK_ALIGN_CENTER);
+
+  item = gtk_tool_button_new_from_stock (GTK_STOCK_GO_FORWARD);
+  gtk_toolbar_insert (GTK_TOOLBAR (toolbar), item, -1);
+
+  item = gtk_tool_button_new_from_stock (GTK_STOCK_GO_BACK);
+  gtk_toolbar_insert (GTK_TOOLBAR (toolbar), item, -1);
+
+  item = gtk_tool_button_new (NULL, "Hello World");
+  gtk_tool_item_set_is_important (item, TRUE);
+  gtk_toolbar_insert (GTK_TOOLBAR (toolbar), item, -1);
+
+  return toolbar;
+}
+
+GtkWidget *
+do_css_shadows (GtkWidget *do_widget)
+{
+  if (!window)
+    {
+      GtkWidget *paned, *container, *child;
+      GtkStyleProvider *provider;
+      GtkTextBuffer *text;
+      GBytes *bytes;
+      
+      window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+      gtk_window_set_transient_for (GTK_WINDOW (window), GTK_WINDOW (do_widget));
+      gtk_window_set_default_size (GTK_WINDOW (window), 400, 300);
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (gtk_widget_destroyed), &window);
+
+      paned = gtk_paned_new (GTK_ORIENTATION_VERTICAL);
+      gtk_container_add (GTK_CONTAINER (window), paned);
+
+      child = create_toolbar ();
+      gtk_container_add (GTK_CONTAINER (paned), child);
+
+      text = gtk_text_buffer_new (NULL);
+      gtk_text_buffer_create_tag (text,
+                                  "warning",
+                                  "underline", PANGO_UNDERLINE_SINGLE,
+                                  NULL);
+      gtk_text_buffer_create_tag (text,
+                                  "error",
+                                  "underline", PANGO_UNDERLINE_ERROR,
+                                  NULL);
+
+      provider = GTK_STYLE_PROVIDER (gtk_css_provider_new ());
+      
+      container = gtk_scrolled_window_new (NULL, NULL);
+      gtk_container_add (GTK_CONTAINER (paned), container);
+      child = gtk_text_view_new_with_buffer (text);
+      gtk_container_add (GTK_CONTAINER (container), child);
+      g_signal_connect (text,
+                        "changed",
+                        G_CALLBACK (css_text_changed),
+                        provider);
+
+      bytes = g_resources_lookup_data ("/css_shadows/gtk.css", 0, NULL);
+      gtk_text_buffer_set_text (text, g_bytes_get_data (bytes, NULL), g_bytes_get_size (bytes));
+
+      g_signal_connect (provider,
+                        "parsing-error",
+                        G_CALLBACK (show_parsing_error),
+                        gtk_text_view_get_buffer (GTK_TEXT_VIEW (child)));
+
+      apply_css (window, provider);
+    }
+
+  if (!gtk_widget_get_visible (window))
+    gtk_widget_show_all (window);
+  else
+    {
+      gtk_widget_destroy (window);
+      window = NULL;
+    }
+
+  return window;
+}
diff --git a/demos/gtk-demo/css_shadows.css b/demos/gtk-demo/css_shadows.css
new file mode 100644
index 0000000..b38e229
--- /dev/null
+++ b/demos/gtk-demo/css_shadows.css
@@ -0,0 +1,44 @@
+/* You can edit the text in this window to change the
+ * appearance of this Window.
+ * Be careful, if you screw it up, nothing might be visible
+ * anymore. :)
+ */
+
+/* This CSS resets all properties to their defaults values
+ *    and overrides all user settings and the theme in use */
+ import url("reset.css");
+ import url("cssview.css");
+
+/* Get a nice background for the window */
+.background {
+  background-color: #4870bc;
+  background-image: linear-gradient(to left, transparent, rgba(255,255,255,.07) 50%, transparent 50%),
+                    linear-gradient(to left, transparent, rgba(255,255,255,.13) 50%, transparent 50%),
+                    linear-gradient(to left, transparent, transparent 50%, rgba(255,255,255,.17) 50%),
+                    linear-gradient(to left, transparent, transparent 50%, rgba(255,255,255,.19) 50%);
+  background-size: 29px, 59px, 73px, 109px;
+}
+
+.button {
+  color: black;
+  padding: 10px;
+  border-radius: 5px;
+  transition: all 250ms ease-in;
+  border: 1px transparent solid;
+}
+
+.button:hover {
+  text-shadow: 3px 3px 5px alpha(black, 0.75);
+  icon-shadow: 3px 3px 5px alpha(black, 0.75);
+  box-shadow: 3px 3px 5px alpha(black, 0.5) inset;
+  border: solid 1px alpha(black, 0.75);
+}
+
+.button:active {
+  padding: 11px 9px 9px 11px;
+  text-shadow: 1px 1px 2.5px alpha(black, 0.6);
+  icon-shadow: 1px 1px 2.5px alpha(black, 0.6);
+}
+
+
+
diff --git a/demos/gtk-demo/demo.gresource.xml b/demos/gtk-demo/demo.gresource.xml
index 8931545..1231ded 100644
--- a/demos/gtk-demo/demo.gresource.xml
+++ b/demos/gtk-demo/demo.gresource.xml
@@ -39,4 +39,7 @@
     <file>gnome-gsame.png</file>
     <file>gnu-keys.png</file>
   </gresource>
+  <gresource prefix="/css_shadows">
+    <file alias="gtk.css">css_shadows.css</file>
+  </gresource>
 </gresources>