Sets a new widget to be attached to popover. If popover is
visible, the position will be updated.
Note: the ownership of popovers is always given to their relative_to
widget, so if relative_to is set to NULL on an attached popover, it
will be detached from its previous widget, and consequently destroyed
unless extra references are kept.
Sets a new widget to be attached to popover. If popover is visible, the position will be updated.
Note: the ownership of popovers is always given to their relative_to widget, so if relative_to is set to NULL on an attached popover, it will be detached from its previous widget, and consequently destroyed unless extra references are kept.