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ChildProxy
===================================================================

.. currentmodule:: gi.repository.Gst





.. class:: ChildProxy(*args, **kwargs)
   :no-contents-entry:





Implementations: :class:`~gi.repository.Gst.Bin`, :class:`~gi.repository.Gst.Pipeline`


This interface abstracts handling of property sets for elements with
children. Imagine elements such as mixers or polyphonic generators. They all
have multiple :obj:`~gi.repository.Gst.Pad` or some kind of voice objects. Another use case are
container elements like :obj:`~gi.repository.Gst.Bin`\.
The element implementing the interface acts as a parent for those child
objects.

By implementing this interface the child properties can be accessed from the
parent element by using :func:`~gi.repository.Gst.ChildProxy.get` and :func:`~gi.repository.Gst.ChildProxy.set`.

Property names are written as ``child-name::property-name``\. The whole naming
scheme is recursive. Thus ``child1::child2::property`` is valid too, if
``child1`` and ``child2`` implement the :obj:`~gi.repository.Gst.ChildProxy` interface.




Methods
-------

.. rst-class:: interim-class

.. class:: ChildProxy
   :no-index:


   .. method:: child_added(child: ~gi.repository.GObject.Object, name: str) -> None

      Emits the :obj:`~gi.repository.Gst.ChildProxy`\::child-added signal.






      :param child: the newly added child

      :param name: the name of the new child




   .. method:: child_removed(child: ~gi.repository.GObject.Object, name: str) -> None

      Emits the :obj:`~gi.repository.Gst.ChildProxy`\::child-removed signal.






      :param child: the removed child

      :param name: the name of the old child




   .. method:: get_child_by_index(index: int) -> ~gi.repository.GObject.Object | None

      Fetches a child by its number.






      :param index: the child's position in the child list




   .. method:: get_child_by_name(name: str) -> ~gi.repository.GObject.Object | None

      Looks up a child element by the given name.

      This virtual method has a default implementation that uses :obj:`~gi.repository.Gst.Object`
      together with :func:`~gi.repository.Gst.Object.get_name`. If the interface is to be used with
      :obj:`~gi.repository.GObject.Object`\, this methods needs to be overridden.






      :param name: the child's name




   .. method:: get_child_by_name_recurse(name: str) -> ~gi.repository.GObject.Object | None

      Looks up a child element by the given full-path name.

      Similar to :func:`~gi.repository.Gst.ChildProxy.get_child_by_name`, this method
      searches and returns a child given a name. The difference is that
      this method allows a hierarchical path in the form of
      child1::child2::child3. In the later example this method would
      return a reference to child3, if found. The name should be made of
      element names only and should not contain any property names.


      .. versionadded:: 1.22





      :param name: the full-path child's name




   .. method:: get_children_count() -> int

      Gets the number of child objects this parent contains.









   .. method:: get_property(name: str) -> ~gi.repository.GObject.Value

      Gets a single property using the GstChildProxy mechanism.
      You are responsible for freeing it by calling :func:`~gi.repository.GObject.Value.unset`






      :param name: name of the property




   .. method:: lookup(name: str) -> ~typing.Tuple[bool, ~gi.repository.GObject.Object, ~gi.overrides.GObject.ParamSpec]

      Looks up which object and :obj:`~gi.repository.GObject.ParamSpec` would be effected by the given ``name``\.






      :param name: name of the property to look up




   .. method:: set_property(name: str, value: ~gi.repository.GObject.Value) -> None

      Sets a single property using the GstChildProxy mechanism.






      :param name: name of the property to set

      :param value: new :obj:`~gi.repository.GObject.Value` for the property










Signals
-------

.. rst-class:: interim-class

.. class:: ChildProxy.signals
   :no-index:
   

   .. method:: child_added(object: ~gi.repository.GObject.Object, name: str) -> None

      The type of the None singleton.







      :param object: the :obj:`~gi.repository.GObject.Object` that was added

      :param name: the name of the new child




   .. method:: child_removed(object: ~gi.repository.GObject.Object, name: str) -> None

      The type of the None singleton.







      :param object: the :obj:`~gi.repository.GObject.Object` that was removed

      :param name: the name of the old child








Virtual Methods
---------------

.. rst-class:: interim-class

.. class:: ChildProxy
   :no-index:
   

   .. method:: do_child_added(child: ~gi.repository.GObject.Object, name: str) -> None

      Emits the :obj:`~gi.repository.Gst.ChildProxy`\::child-added signal.






      :param child: the newly added child

      :param name: the name of the new child




   .. method:: do_child_removed(child: ~gi.repository.GObject.Object, name: str) -> None

      Emits the :obj:`~gi.repository.Gst.ChildProxy`\::child-removed signal.






      :param child: the removed child

      :param name: the name of the old child




   .. method:: do_get_child_by_index(index: int) -> ~gi.repository.GObject.Object | None

      Fetches a child by its number.






      :param index: the child's position in the child list




   .. method:: do_get_child_by_name(name: str) -> ~gi.repository.GObject.Object | None

      Looks up a child element by the given name.

      This virtual method has a default implementation that uses :obj:`~gi.repository.Gst.Object`
      together with :func:`~gi.repository.Gst.Object.get_name`. If the interface is to be used with
      :obj:`~gi.repository.GObject.Object`\, this methods needs to be overridden.






      :param name: the child's name




   .. method:: do_get_children_count() -> int

      Gets the number of child objects this parent contains.