Здравствуйте.

type
TNewComponent = class(...)
private
{ Private declarations }
FNewEvent: TNotifyEvent;
protected
{ Protected declarations }
public
{ Public declarations }
published
{ Published declarations }
property OnNewEvent: TNotifyEvent read FNewEvent write FNewEvent;
end;


Далее в коде:

if FNewEvent <> nil then
FNewEvent(Self);


Желаю успехов.