gtk2/demos/gtk-demo/css_basics.c
2012-05-30 13:17:22 -04:00

134 lines
4.2 KiB
C

/* CSS Theming/CSS Basics
*
* Gtk themes are written using CSS. Every widget is build of multiple items
* that you can style very similarly to a regular website.
*
*/
#include <gtk/gtk.h>
static GtkWidget *window = NULL;
#define DEFAULT_CSS \
"/* You can edit the CSS to change the appearance of this Window */\n" \
"\n" \
"GtkWindow {\n" \
" engine: none;\n" \
" background-image: none;\n" \
" background-color: brown;\n" \
"}\n" \
"\n" \
"GtkTextView {\n" \
" color: green;\n" \
"}\n" \
"\n"
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 *
do_css_basics (GtkWidget *do_widget)
{
if (!window)
{
GtkWidget *container, *child;
GtkStyleProvider *provider;
GtkTextBuffer *text;
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);
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 (window), 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);
gtk_text_buffer_set_text (text,
DEFAULT_CSS,
-1);
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;
}