the anchor GdkRectangle to align @surface with
the point on @anchor_rect to align with @surface's anchor point
the point on @surface to align with @rect's anchor point
newly created instance of GdkPopupLayout
ConstructionException GTK+ fails to create the object.
Create a popup layout description.
Used together with [method@Gdk.Popup.present] to describe how a popup surface should be placed and behave on-screen.
@anchor_rect is relative to the top-left corner of the surface's parent. @rect_anchor and @surface_anchor determine anchor points on @anchor_rect and surface to pin together.
The position of @anchor_rect's anchor point can optionally be offset using [method@Gdk.PopupLayout.set_offset], which is equivalent to offsetting the position of surface.