Used together with gdk.popup.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
gdk.popup_layout.PopupLayout.setOffset, which is equivalent to offsetting the
position of surface.
Create a popup layout description.
Used together with gdk.popup.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 gdk.popup_layout.PopupLayout.setOffset, which is equivalent to offsetting the position of surface.