In the source I write this command to assing a clientevent.extevent. If run the application it does not work bud if I assign this in dessign time work ok. z := 'afterrender=function afterrender(sender, eOpts) { sender.allowBlank = false; }'; TUniDBDateTimePicker(edit).ClientEvents.ExtEvents.Add( z ); I need make another job to meke work this code??