:right-sidebar: True CellLayout =================================================================== .. currentmodule:: gi.repository.Gtk .. deprecated:: 4.10 List views use widgets to display their contents. See :obj:`~gi.repository.Gtk.LayoutManager` for layout manager delegate objects .. class:: CellLayout(*args, **kwargs) :no-contents-entry: Implementations: :class:`~gi.repository.Gtk.CellArea`, :class:`~gi.repository.Gtk.CellAreaBox`, :class:`~gi.repository.Gtk.CellView`, :class:`~gi.repository.Gtk.ComboBox`, :class:`~gi.repository.Gtk.ComboBoxText`, :class:`~gi.repository.Gtk.EntryCompletion`, :class:`~gi.repository.Gtk.IconView`, :class:`~gi.repository.Gtk.TreeViewColumn` An interface for packing cells ``GtkCellLayout`` is an interface to be implemented by all objects which want to provide a ``GtkTreeViewColumn`` like API for packing cells, setting attributes and data funcs. One of the notable features provided by implementations of ``GtkCellLayout`` are attributes. Attributes let you set the properties in flexible ways. They can just be set to constant values like regular properties. But they can also be mapped to a column of the underlying tree model with :func:`~gi.repository.Gtk.CellLayout.set_attributes`, which means that the value of the attribute can change from cell to cell as they are rendered by the cell renderer. Finally, it is possible to specify a function with :func:`~gi.repository.Gtk.CellLayout.set_cell_data_func` that is called to determine the value of the attribute for each cell that is rendered. GtkCellLayouts as GtkBuildable -------------------------------------------------------------------------------- Implementations of GtkCellLayout which also implement the GtkBuildable interface (``GtkCellView``\, ``GtkIconView``\, ``GtkComboBox``\, ``GtkEntryCompletion``\, ``GtkTreeViewColumn``\) accept ``GtkCellRenderer`` objects as ```` elements in UI definitions. They support a custom ```` element for their children, which can contain multiple ```` elements. Each ```` element has a name attribute which specifies a property of the cell renderer; the content of the element is the attribute value. This is an example of a UI definition fragment specifying attributes: .. code-block:: xml :dedent: 0 Furthermore for implementations of ``GtkCellLayout`` that use a ``GtkCellArea`` to lay out cells (all ``GtkCellLayout``\s in GTK use a ``GtkCellArea``\) `cell properties `__ can also be defined in the format by specifying the custom ```` attribute which can contain multiple ```` elements. Here is a UI definition fragment specifying cell properties: .. code-block:: xml :dedent: True False Subclassing GtkCellLayout implementations -------------------------------------------------------------------------------- When subclassing a widget that implements ``GtkCellLayout`` like ``GtkIconView`` or ``GtkComboBox``\, there are some considerations related to the fact that these widgets internally use a ``GtkCellArea``\. The cell area is exposed as a construct-only property by these widgets. This means that it is possible to e.g. do .. code-block:: c :dedent: GtkWIdget *combo = g_object_new (GTK_TYPE_COMBO_BOX, "cell-area", my_cell_area, NULL); to use a custom cell area with a combo box. But construct properties are only initialized after instance ``init()`` functions have run, which means that using functions which rely on the existence of the cell area in your subclass ``init()`` function will cause the default cell area to be instantiated. In this case, a provided construct property value will be ignored (with a warning, to alert you to the problem). .. code-block:: c :dedent: static void my_combo_box_init (MyComboBox *b) { GtkCellRenderer *cell; cell = gtk_cell_renderer_pixbuf_new (); // The following call causes the default cell area for combo boxes, // a GtkCellAreaBox, to be instantiated gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (b), cell, FALSE); ... } GtkWidget * my_combo_box_new (GtkCellArea *area) { // This call is going to cause a warning about area being ignored return g_object_new (MY_TYPE_COMBO_BOX, "cell-area", area, NULL); } If supporting alternative cell areas with your derived widget is not important, then this does not have to concern you. If you want to support alternative cell areas, you can do so by moving the problematic calls out of ``init()`` and into a ``constructor()`` for your class. Methods ------- .. rst-class:: interim-class .. class:: CellLayout :no-index: .. method:: add_attribute(cell: ~gi.repository.Gtk.CellRenderer, attribute: str, column: int) -> None Adds an attribute mapping to the list in ``cell_layout``\. The ``column`` is the column of the model to get a value from, and the ``attribute`` is the property on ``cell`` to be set from that value. So for example if column 2 of the model contains strings, you could have the “text” attribute of a ``GtkCellRendererText`` get its values from column 2. In this context "attribute" and "property" are used interchangeably. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param attribute: a property on the renderer :param column: the column position on the model to get the attribute from .. method:: clear() -> None Unsets all the mappings on all renderers on ``cell_layout`` and removes all renderers from ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: clear_attributes(cell: ~gi.repository.Gtk.CellRenderer) -> None Clears all existing attributes previously set with :func:`~gi.repository.Gtk.CellLayout.set_attributes`. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` to clear the attribute mapping on .. method:: get_area() -> ~gi.repository.Gtk.CellArea | None Returns the underlying ``GtkCellArea`` which might be ``cell_layout`` if called on a ``GtkCellArea`` or might be :const:`None` if no ``GtkCellArea`` is used by ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: get_cells() -> list[~gi.repository.Gtk.CellRenderer] Returns the cell renderers which have been added to ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: pack_end(cell: ~gi.repository.Gtk.CellRenderer, expand: bool) -> None Adds the ``cell`` to the end of ``cell_layout``\. If ``expand`` is :const:`False`, then the ``cell`` is allocated no more space than it needs. Any unused space is divided evenly between cells for which ``expand`` is :const:`True`. Note that reusing the same cell renderer is not supported. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param expand: :const:`True` if ``cell`` is to be given extra space allocated to ``cell_layout`` .. method:: pack_start(cell: ~gi.repository.Gtk.CellRenderer, expand: bool) -> None Packs the ``cell`` into the beginning of ``cell_layout``\. If ``expand`` is :const:`False`, then the ``cell`` is allocated no more space than it needs. Any unused space is divided evenly between cells for which ``expand`` is :const:`True`. Note that reusing the same cell renderer is not supported. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param expand: :const:`True` if ``cell`` is to be given extra space allocated to ``cell_layout`` .. method:: reorder(cell: ~gi.repository.Gtk.CellRenderer, position: int) -> None Re-inserts ``cell`` at ``position``\. Note that ``cell`` has already to be packed into ``cell_layout`` for this to function properly. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` to reorder :param position: new position to insert ``cell`` at .. method:: set_cell_data_func(cell: ~gi.repository.Gtk.CellRenderer, func: ~typing.Callable[[~gi.repository.Gtk.CellLayout, ~gi.repository.Gtk.CellRenderer, ~gi.repository.Gtk.TreeModel, ~gi.repository.Gtk.TreeIter, ~typing.Any], None] | None = None, func_data: ~typing.Any = None) -> None Sets the ``GtkCellLayout``\DataFunc to use for ``cell_layout``\. This function is used instead of the standard attributes mapping for setting the column value, and should set the value of ``cell_layout``\’s cell renderer(s) as appropriate. ``func`` may be :const:`None` to remove a previously set function. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param func: the ``GtkCellLayout``\DataFunc to use :param func_data: user data for ``func`` Virtual Methods --------------- .. rst-class:: interim-class .. class:: CellLayout :no-index: .. method:: do_add_attribute(cell: ~gi.repository.Gtk.CellRenderer, attribute: str, column: int) -> None Adds an attribute mapping to the list in ``cell_layout``\. The ``column`` is the column of the model to get a value from, and the ``attribute`` is the property on ``cell`` to be set from that value. So for example if column 2 of the model contains strings, you could have the “text” attribute of a ``GtkCellRendererText`` get its values from column 2. In this context "attribute" and "property" are used interchangeably. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param attribute: a property on the renderer :param column: the column position on the model to get the attribute from .. method:: do_clear() -> None Unsets all the mappings on all renderers on ``cell_layout`` and removes all renderers from ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: do_clear_attributes(cell: ~gi.repository.Gtk.CellRenderer) -> None Clears all existing attributes previously set with :func:`~gi.repository.Gtk.CellLayout.set_attributes`. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` to clear the attribute mapping on .. method:: do_get_area() -> ~gi.repository.Gtk.CellArea | None Returns the underlying ``GtkCellArea`` which might be ``cell_layout`` if called on a ``GtkCellArea`` or might be :const:`None` if no ``GtkCellArea`` is used by ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: do_get_cells() -> list[~gi.repository.Gtk.CellRenderer] Returns the cell renderers which have been added to ``cell_layout``\. .. deprecated:: 4.10 Please do not use it in newly written code .. method:: do_pack_end(cell: ~gi.repository.Gtk.CellRenderer, expand: bool) -> None Adds the ``cell`` to the end of ``cell_layout``\. If ``expand`` is :const:`False`, then the ``cell`` is allocated no more space than it needs. Any unused space is divided evenly between cells for which ``expand`` is :const:`True`. Note that reusing the same cell renderer is not supported. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param expand: :const:`True` if ``cell`` is to be given extra space allocated to ``cell_layout`` .. method:: do_pack_start(cell: ~gi.repository.Gtk.CellRenderer, expand: bool) -> None Packs the ``cell`` into the beginning of ``cell_layout``\. If ``expand`` is :const:`False`, then the ``cell`` is allocated no more space than it needs. Any unused space is divided evenly between cells for which ``expand`` is :const:`True`. Note that reusing the same cell renderer is not supported. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param expand: :const:`True` if ``cell`` is to be given extra space allocated to ``cell_layout`` .. method:: do_reorder(cell: ~gi.repository.Gtk.CellRenderer, position: int) -> None Re-inserts ``cell`` at ``position``\. Note that ``cell`` has already to be packed into ``cell_layout`` for this to function properly. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` to reorder :param position: new position to insert ``cell`` at .. method:: do_set_cell_data_func(cell: ~gi.repository.Gtk.CellRenderer, func: ~typing.Callable[[~gi.repository.Gtk.CellLayout, ~gi.repository.Gtk.CellRenderer, ~gi.repository.Gtk.TreeModel, ~gi.repository.Gtk.TreeIter, ~typing.Any], None] | None = None, func_data: ~typing.Any = None) -> None Sets the ``GtkCellLayout``\DataFunc to use for ``cell_layout``\. This function is used instead of the standard attributes mapping for setting the column value, and should set the value of ``cell_layout``\’s cell renderer(s) as appropriate. ``func`` may be :const:`None` to remove a previously set function. .. deprecated:: 4.10 Please do not use it in newly written code :param cell: a ``GtkCellRenderer`` :param func: the ``GtkCellLayout``\DataFunc to use :param func_data: user data for ``func``