组件无法显示，为什么？急急！！

我做了一个组件，经过注册，但是却没有显示出来，查看Samples中所含的组件中却有我的组件，这是什么原因呢？？程序如下：
unit Qdir;interfaceuses
  SysUtils, Classes, QControls, QStdCtrls;type
  Tdir = class(TButton)
  private
    { Private declarations }
    //name:string;
    //pro:string;
    //direction:string;
    //procedure lookup(n,p,d:string);
    //function dir(x1,x2,y1,y2,a1,a2,b1,b2:double):string;
  protected
    { Protected declarations }
  public
    { Public declarations }
    name:string;
    pro:string;
    direction:string;
    procedure lookup(n,p,d:string);
    function dir(x1,x2,y1,y2,a1,a2,b1,b2:double):string;
    constructor Create(AOwner:TComponent);
  published
    { Published declarations }
  end;procedure Register;implementation
constructor Tdir.Create(AOwner:TComponent);
begin
  inherited Create(AOwner);
  Enabled:=True;
  Visible:=True;
  Height:=25;
  Width:=75;
end;procedure Tdir.lookup(n,p,d:string);
begin
  name:=n;
  pro:=p;
  direction:=d;
end;function Tdir.dir(x1,x2,y1,y2,a1,a2,b1,b2:double):string;
begin
 if((a2<=x1)and(b1>=y2))then
  result:='NW';//NW
 if((x1<=a1)and(a2<=x2)and(b1>=y2))then
  result:='RN';//RN
 if((a1>=x2)and(b1>=y2))then
  result:='NE';//NE
 if((y1<=b1)and(b2<=y2)and(a2<=x1))then
  result:='RW';//RW
 if((y1<=b1)and(b2<=y2)and(a1>=x2))then
  result:='RE';//RE
 if((a2<=x1)and(b2<=y2))then
  result:='SW';//SW
 if((x1<=a1)and(a2<=x2)and(b2<=y1))then
  result:='RS';//RS
 if((a1>=x2)and(b2<=y1))then
  result:='SE';//SE
 if((b1>=y2)and(x1<a1)and(a1<x2))then
  result:='N';//N
 if((b1>=y2)and(x1<a2)and(a2<x2))then
  result:='N';//N
 if((b1>=y2)and(a1<x1)and(a2>x2))then
  result:='N';//N
 if((b2<=y1)and(x1<a1)and(a1<x2))then
  result:='S';//S
 if((b2<=y1)and(x1<a2)and(a2<x2))then
  result:='S';//S
 if((b2<=y1)and(a1<x1)and(a2>x2))then
  result:='S';//S
 if((a2<=x1)and(y1<b1)and(b1<y2))then
  result:='W';//W
 if((a2<=x1)and(y1<b2)and(b1<y2))then
  result:='W';//W
 if((a2<=x1)and(b1<y1)and(b2>y2))then
  result:='W';//W
 if((a1>=x2)and(y1<b1)and(b1<y2))then
  result:='W';//W
 if((a1>=x2)and(y1<b2)and(b1<y2))then
  result:='W';//W
 if((a1>=x2)and(b1<y1)and(b2>y2))then
  result:='W';//W
 if((a2>x1)and(b1<y2)and(a1<x1)and(b2>y2))then
  result:='SA';//SA
 if((a1<x2)and(b1<y2)and(a2>x2)and(b2>y2))then
  result:='SA';//SA
 if((a2>x1)and(b2>y1)and(a1<x1)and(b1<y1))then
  result:='SA';//SA
 if((a1<x2)and(b2>y1)and(a2>x2)and(b1<y1))then
  result:='SA';//SA
 if((x1<=a1)and(a2<=x2)and(y1<=b1)and(b2<=y2))then
  result:='SA';//SA
 if((a1<x1)and(a2>x2)and(b1<y1)and(b2>y2))then
  result:='SA';//SA
end;
procedure Register;
begin
  RegisterComponents('Samples', [Tdir]);
end;end.