a #GdkEvent
widget that received the event
widget-dependent string representation of the event location; e.g. for #GtkTreeView, a string representation of #GtkTreePath
background area as passed to gtk_cell_renderer_render()
cell area as passed to gtk_cell_renderer_render()
render flags
Return: A new #GtkCellEditable, or %NULL
Passes an activate event to the cell renderer for possible processing.