fnEventHandler = (oEvent, sVMTargetElementId) => {
						const oCreatedOverlay = oEvent.getParameter("elementOverlay");
						if (oCreatedOverlay.getElement().getId() === sVMTargetElementId) {
							this._propagateVariantManagement(oCreatedOverlay, sVariantManagementReference);
							this.getDesignTime().detachEvent("elementOverlayCreated", fnEventHandler);
						}
					}
Registers an overlay.

@param {sap.ui.dt.Overlay} oOverlay overlay object
@override