private static CustomPopupPlacement[] CustomPopupPlacementCallback(Size popupSize, Size targetSize, Point offset) {
return new [] {
new CustomPopupPlacement {
Point = new Point(targetSize.Width - 12, -targetSize.Height - 200),
PrimaryAxis = PopupPrimaryAxis.Vertical
},
new CustomPopupPlacement {
Point = new Point(-popupSize.Width, -targetSize.Height - 200),
PrimaryAxis = PopupPrimaryAxis.Vertical
},
};
}