Parsing of custom resources: GTK+ 3 Reference Manual

Parsing of custom resources

As a consequence of the RC format going away, calling gtk_rc_parse() or gtk_rc_parse_string() won't have any effect on a widgets appearance. The way to replace these calls is using a custom GtkStyleProvider, either for an individual widget through gtk_style_context_add_provider() or for all widgets on a screen through gtk_style_context_add_provider_for_screen(). Typically, the provider will be a GtkCssProvider, which parse CSS information from a file or from a string.

Example 49. Using a custom GtkStyleProvider

        GtkStyleContext *context;
        GtkCssProvider *provider;

        context = gtk_widget_get_style_context (widget);
        provider = gtk_css_provider_new ();
        gtk_css_provider_load_from_data (GTK_CSS_PROVIDER (provider),
                                         ".frame1 {\n"
                                         "   border-image: url('gradient1.png') 10 10 10 10 stretch;\n"
                                         "}\n", -1, NULL);
        gtk_style_context_add_provider (context,
                                        GTK_STYLE_PROVIDER (provider),
                                        GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);
        g_object_unref (provider);

Notice that you can also get style information from custom resources by implementing the GtkStyleProvider interface yourself. This is an advanced feature that should be rarely used.