Constraining Drag to Y axis

I’m wondering if theres a way to constrain drag operations in my timeline to vertical moves. Originally, I thought i could just compare the value changes before and after drag / drop, but since i’m using essentially a Day view, it tends to slide around a bit

try using ‘onBeforeEventChanged’ and just reset start/end dates to old values after d’n’d … entchanged
Event handler may be pretty simplescheduler.attachEvent("onBeforeEventChanged", function(event_object, native_event, is_new, unmodified_event){ if(scheduler.getState().mode == "timeline" && !is_new){ event_object.start_date = new Date(unmodified_event.start_date); event_object.end_date = new Date(unmodified_event.end_date); } return true; });