:right-sidebar: True

CssProvider
===================================================================

.. currentmodule:: gi.repository.Gtk





.. class:: CssProvider(**properties: ~typing.Any)
   :no-contents-entry:


Superclasses: :class:`~gi.repository.GObject.Object`



Implemented Interfaces: :class:`~gi.repository.Gtk.StyleProvider`



``GtkCssProvider`` is an object implementing the ``GtkStyleProvider`` interface
for CSS.

It is able to parse CSS-like input in order to style widgets.

An application can make GTK parse a specific CSS style sheet by calling
:obj:`~gi.repository.Gtk.CssProvider.load_from_file` or
:obj:`~gi.repository.Gtk.CssProvider.load_from_resource`
and adding the provider with :obj:`~gi.repository.Gtk.StyleContext.add_provider` or
:obj:`~gi.repository.Gtk.StyleContext.add_provider_for_display`.

In addition, certain files will be read when GTK is initialized.
First, the file ``$XDG_CONFIG_HOME/gtk-4.0/gtk.css`` is loaded if it
exists. Then, GTK loads the first existing file among
``XDG_DATA_HOME/themes/THEME/gtk-VERSION/gtk-VARIANT.css``,
``$HOME/.themes/THEME/gtk-VERSION/gtk-VARIANT.css``,
``$XDG_DATA_DIRS/themes/THEME/gtk-VERSION/gtk-VARIANT.css`` and
``DATADIR/share/themes/THEME/gtk-VERSION/gtk-VARIANT.css``,
where ``THEME`` is the name of the current theme (see the
:obj:`~gi.repository.Gtk.Settings.props.gtk_theme_name` setting), ``VARIANT`` is the
variant to load (see the
:obj:`~gi.repository.Gtk.Settings.props.gtk_application_prefer_dark_theme` setting),
``DATADIR`` is the prefix configured when GTK was compiled (unless
overridden by the ``GTK_DATA_PREFIX`` environment variable), and
``VERSION`` is the GTK version number. If no file is found for the
current version, GTK tries older versions all the way back to 4.0.

To track errors while loading CSS, connect to the
:obj:`~gi.repository.Gtk.CssProvider.signals.parsing_error` signal.



Constructors
------------

.. rst-class:: interim-class

.. class:: CssProvider
   :no-index:


   .. classmethod:: new() -> ~gi.repository.Gtk.CssProvider

      Returns a newly created ``GtkCssProvider``.














Methods
-------

.. rst-class:: interim-class

.. class:: CssProvider
   :no-index:


   .. method:: load_from_bytes(data: ~gi.repository.GLib.Bytes) -> None

      Loads ``data`` into ``css_provider``.

      This clears any previously loaded information.



      .. versionadded:: 4.12





      :param data: ``GBytes`` containing the data to load





   .. method:: load_from_data(text, length=-1)

      Loads ``data`` into ``css_provider``.

      This clears any previously loaded information.






      .. deprecated:: 4.12

         Use :obj:`~gi.repository.Gtk.CssProvider.load_from_string`
         or :obj:`~gi.repository.Gtk.CssProvider.load_from_bytes` instead




      :param text: 

      :param length: the length of ``data`` in bytes, or -1 for NUL terminated strings





   .. method:: load_from_file(file: ~gi.repository.Gio.File) -> None

      Loads the data contained in ``file`` into ``css_provider``.

      This clears any previously loaded information.







      :param file: ``GFile`` pointing to a file to load





   .. method:: load_from_path(path: str) -> None

      Loads the data contained in ``path`` into ``css_provider``.

      This clears any previously loaded information.







      :param path: the path of a filename to load, in the GLib filename encoding





   .. method:: load_from_resource(resource_path: str) -> None

      Loads the data contained in the resource at ``resource_path`` into
      the ``css_provider``.

      This clears any previously loaded information.







      :param resource_path: a ``GResource`` resource path





   .. method:: load_from_string(string: str) -> None

      Loads ``string`` into ``css_provider``.

      This clears any previously loaded information.



      .. versionadded:: 4.12





      :param string: the CSS to load





   .. method:: load_named(name: str, variant: str | None = None) -> None

      Loads a theme from the usual theme paths.

      The actual process of finding the theme might change between
      releases, but it is guaranteed that this function uses the same
      mechanism to load the theme that GTK uses for loading its own theme.







      :param name: A theme name


      :param variant: variant to load, for example, "dark", or
         :const:`None` for the default





   .. method:: to_string() -> str

      Converts the ``provider`` into a string representation in CSS
      format.

      Using :obj:`~gi.repository.Gtk.CssProvider.load_from_string` with the return
      value from this function on a new provider created with
      :obj:`~gi.repository.Gtk.CssProvider.new` will basically create a duplicate
      of this ``provider``.
















Signals
-------

.. rst-class:: interim-class

.. class:: CssProvider.signals
   :no-index:
   

   .. method:: parsing_error(section: ~gi.repository.Gtk.CssSection, error: ~gi.repository.GLib.GError) -> None

      Signals that a parsing error occurred.

      The ``path``, ``line`` and ``position`` describe the actual location of
      the error as accurately as possible.

      Parsing errors are never fatal, so the parsing will resume after
      the error. Errors may however cause parts of the given data or
      even all of it to not be parsed at all. So it is a useful idea
      to check that the parsing succeeds by connecting to this signal.

      Note that this signal may be emitted at any time as the css provider
      may opt to defer parsing parts or all of the input to a later time
      than when a loading function was called.







      :param section: section the error happened in


      :param error: The parsing error











Fields
------

.. rst-class:: interim-class

.. class:: CssProvider
   :no-index:
   

   .. attribute:: parent_instance