. Definicja klasy TButClock.
unit Tbc;

interface

uses
  SysUtils, Windows, Messages, Classes, Graphics, Controls,
  Forms, Dialogs, StdCtrls, ExtCtrls;

type
  TButClock = class(TButton)
  private
    { Private declarations }
    MainTimer: TTimer;
    procedure LoopTime(Sender: TObject);
  protected
    { Protected declarations }
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
  published
    { Published declarations }
  end;

procedure Register;