gtk/demos/gtk-demo/css_basics.c
Matthias Clasen 386b63b85d scrolledwindow: Don't take adjustments in new()
In 99.9% of all cases, these are just NULL, NULL.
So just do away with these arguments, people can
use the setters for the rare cases where they want
the scrolled window to use a different adjustment.
2020-06-24 11:25:09 -04:00

123 lines
3.9 KiB
C

/* 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 void
show_parsing_error (GtkCssProvider *provider,
GtkCssSection *section,
const GError *error,
GtkTextBuffer *buffer)
{
const GtkCssLocation *start_location, *end_location;
GtkTextIter start, end;
const char *tag_name;
start_location = gtk_css_section_get_start_location (section);
gtk_text_buffer_get_iter_at_line_index (buffer,
&start,
start_location->lines,
start_location->line_bytes);
end_location = gtk_css_section_get_end_location (section);
gtk_text_buffer_get_iter_at_line_index (buffer,
&end,
end_location->lines,
end_location->line_bytes);
if (error->domain == GTK_CSS_PARSER_WARNING)
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);
g_free (text);
}
static void
apply_css (GtkWidget *widget, GtkStyleProvider *provider)
{
GtkWidget *child;
gtk_style_context_add_provider (gtk_widget_get_style_context (widget), provider, G_MAXUINT);
for (child = gtk_widget_get_first_child (widget);
child != NULL;
child = gtk_widget_get_next_sibling (child))
apply_css (child, provider);
}
GtkWidget *
do_css_basics (GtkWidget *do_widget)
{
static GtkWidget *window = NULL;
if (!window)
{
GtkWidget *container, *child;
GtkStyleProvider *provider;
GtkTextBuffer *text;
GBytes *bytes;
window = gtk_window_new ();
gtk_window_set_title (GTK_WINDOW (window), "CSS Basics");
gtk_window_set_transient_for (GTK_WINDOW (window), GTK_WINDOW (do_widget));
gtk_window_set_default_size (GTK_WINDOW (window), 400, 300);
g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&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 ();
gtk_window_set_child (GTK_WINDOW (window), container);
child = gtk_text_view_new_with_buffer (text);
gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (container), child);
g_signal_connect (text, "changed",
G_CALLBACK (css_text_changed), provider);
bytes = g_resources_lookup_data ("/css_basics/css_basics.css", 0, NULL);
gtk_text_buffer_set_text (text, g_bytes_get_data (bytes, NULL), g_bytes_get_size (bytes));
g_bytes_unref (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 (window);
else
gtk_window_destroy (GTK_WINDOW (window));
return window;
}