add_focus_sibling

Description:

public void add_focus_sibling (CellRenderer renderer, CellRenderer sibling)

Adds sibling to renderer’s focusable area, focus will be drawn around renderer and all of its siblings if renderer can focus for a given row.

Events handled by focus siblings can also activate the given focusable renderer.

this	a `GtkCellArea`
renderer	the `GtkCellRenderer` expected to have focus
sibling	the `GtkCellRenderer` to add to `renderer`’s focus area