how to set my custom side button region into top(first) position in WDE 8.5?

how to set my custom side button region into top(first) position in WDE 8.5?

viewManager.ViewsByRegionName["CaseViewSideButtonRegion"].Insert(0,new ViewActivator()
                                                {
                                                    ViewType = typeof(ICustomerInfoSideButton),
                                                    ViewName = "CustomInfoButton",
                                                    ActivateView = true
                                                });

when i add this code ,it will display like contact,my custom,Response side button order…actually i need like my custom,contact,response…pls…

I think the list is arranged/sorted alphabetically by default.

i found the solution for it…

Go to interaction workspace configuration add key like :
Key name:views.CaseViewSideButtonRegion.order and set value:CustomInfoButton,InteractionContainerSideButtonView,SRLSideButtonView

;D Thanks for sharing