:right-sidebar: True

ConstraintLayout
===================================================================

.. currentmodule:: gi.repository.Gtk





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


Superclasses: :class:`~gi.repository.Gtk.LayoutManager`, :class:`~gi.repository.GObject.Object`



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



:Constructors:

::

    ConstraintLayout(**properties)
    new() -> Gtk.LayoutManager



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

.. rst-class:: interim-class

.. class:: ConstraintLayout
   :no-index:


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

      Creates a new ``GtkConstraintLayout`` layout manager.














Methods
-------

.. rst-class:: interim-class

.. class:: ConstraintLayout
   :no-index:


   .. method:: add_constraint(constraint: ~gi.repository.Gtk.Constraint) -> None

      Adds a constraint to the layout manager.

      The :obj:`~gi.repository.Gtk.Constraint.props.source` and :obj:`~gi.repository.Gtk.Constraint.props.target`
      properties of ``constraint`` can be:

       - set to ``NULL`` to indicate that the constraint refers to the
         widget using ``layout``
       - set to the :obj:`~gi.repository.Gtk.Widget` using ``layout``
       - set to a child of the :obj:`~gi.repository.Gtk.Widget` using ``layout``
       - set to a :obj:`~gi.repository.Gtk.ConstraintGuide` that is part of ``layout``

      The ``layout`` acquires the ownership of ``constraint`` after calling
      this function.







      :param constraint: a :obj:`~gi.repository.Gtk.Constraint`





   .. method:: add_constraints_from_description(lines: ~typing.Sequence[str], hspacing: int, vspacing: int, views: dict[str, ~gi.repository.Gtk.ConstraintTarget]) -> list[~gi.repository.Gtk.Constraint]

      Creates a list of constraints from a VFL description.

      This function is a convenience wrapper around
      :obj:`~gi.repository.Gtk.ConstraintLayout.add_constraints_from_descriptionv`, using
      variadic arguments to populate the view/target map.







      :param lines: an array of Visual Format Language lines
         defining a set of constraints


      :param hspacing: default horizontal spacing value, or -1 for the fallback value


      :param vspacing: default vertical spacing value, or -1 for the fallback value


      :param views: 




   .. method:: add_guide(guide: ~gi.repository.Gtk.ConstraintGuide) -> None

      Adds a guide to ``layout``.

      A guide can be used as the source or target of constraints,
      like a widget, but it is not visible.

      The ``layout`` acquires the ownership of ``guide`` after calling
      this function.







      :param guide: a :obj:`~gi.repository.Gtk.ConstraintGuide` object





   .. method:: observe_constraints() -> ~gi.repository.Gio.ListModel

      Returns a ``GListModel`` to track the constraints that are
      part of the layout.

      Calling this function will enable extra internal bookkeeping
      to track constraints and emit signals on the returned listmodel.
      It may slow down operations a lot.

      Applications should try hard to avoid calling this function
      because of the slowdowns.










   .. method:: observe_guides() -> ~gi.repository.Gio.ListModel

      Returns a ``GListModel`` to track the guides that are
      part of the layout.

      Calling this function will enable extra internal bookkeeping
      to track guides and emit signals on the returned listmodel.
      It may slow down operations a lot.

      Applications should try hard to avoid calling this function
      because of the slowdowns.










   .. method:: remove_all_constraints() -> None

      Removes all constraints from the layout manager.










   .. method:: remove_constraint(constraint: ~gi.repository.Gtk.Constraint) -> None

      Removes ``constraint`` from the layout manager,
      so that it no longer influences the layout.







      :param constraint: a :obj:`~gi.repository.Gtk.Constraint`





   .. method:: remove_guide(guide: ~gi.repository.Gtk.ConstraintGuide) -> None

      Removes ``guide`` from the layout manager,
      so that it no longer influences the layout.







      :param guide: a :obj:`~gi.repository.Gtk.ConstraintGuide` object