To create a handler class to add further validation to the state machine, follow these steps:

1. Open the ConWHSVehicleInspStatusHandler class and add the following piece of code:

public ConWHSVehInspStatus fromStatus; 
public ConWHSVehInspStatus toStatus; 
public ConWHSVehicleTable vehicle; 

public boolean Validate() 
{ 
    switch (toStatus) 
    { 
        case ConWHSVehInspStatus::Complete: 
            if (vehicle.InspComment == '') 
            { 
                DictField field = new DictField( 
                    tableNum(ConWHSVehicleTable), 
                    fieldNum(ConWHSVehicleTable,  
                             InspComment)); 

                //The field %1 must be filled in" 
                return checkFailed (strFmt( 
                                "@SYS110217",  
                                field.label())); 
            } 
            break; 
    } 
    return true; 
} 

public void run() 
{ 
    if(toStatus == fromStatus) 
    { 
        return; 
    } 
    if(this.Validate()) 
    { 
        switch (toStatus) 
        { 
            case ConWHSVehInspStatus::Complete: 
                Timezone tz = DateTimeUtil:: 
                               getClientMachineTimeZone(); 
                ConWHSVehInspDate inspDate; 
                inspDate = DateTimeUtil::getSystemDate(tz); 
                vehicle.InspDate = inspDate; 
                break; 
        } 
    } 
    else 
    { 
        vehicle.InspStatus = fromStatus; 
    } 
} 

2. The code to tie it to the transition delegate is as follows:

[SubscribesTo(classStr(ConWHSVehicleTableInspStateMachine),  
 delegateStr( 
    ConWHSVehicleTableInspStateMachine, Transition))] 
public static void HandleTransition( 
    ConWHSVehicleTableInspStateMachineTransitionEventArgs  
    _eventArgs) 
{ 
    ConWHSVehicleInspStatusHandler handler; 
    handler = new ConWHSVehicleInspStatusHandler(); 

    handler.vehicle = _eventArgs.DataEntity(); 
    handler.fromStatus = _eventArgs.ExitState(); 
    handler.toStatus = _eventArgs.EnterState(); 
    handler.Run(); 
}