array of tbuttons unit - with some compile errors (2)

unit Unit1;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls;

type

  { TForm1 }

  Tarray_of_tbutton = array of tbutton;
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
    procedure MyArrayButtonsClick(Sender: TObject);
    procedure define_3x3_button_array;
  private
    { private declarations }
  public
    { public declarations }
  end;

var
  Form1: TForm1;
  my_array_of_tbutton : Tarray_of_tbutton;

implementation

{$R *.lfm}

procedure TForm1.MyArrayButtonsClick(Sender: TObject);
begin
  Showmessage( 'You clicked on array button # ' +
    inttostr((Sender as Tbutton).Tag) );
end;

procedure TForm1.define_3x3_button_array;
const
  max_horizontal = 3;
  max_vertical = 3;
var
  v_count, h_count, array_count : integer;
begin
  SetLength( my_array_of_tbutton, max_horizontal * max_vertical );
  for v_count := 0 to max_vertical - 1 do
   for h_count := 0 to max_horizontal - 1 do
     begin
       array_count := v_count * max_horizontal + h_count;
       my_array_of_tbutton[ array_count ] := new( tbutton( my_array_of_tbutton ));
       my_array_of_tbutton[ array_count ].Parent := Self;
       my_array_of_tbutton[ array_count ].Left :=
         50 + h_count * 50;
       my_array_of_tbutton[ array_count ].Top :=
         50 + v_count * 50;
       my_array_of_tbutton[ array_count ].Tag :=
         array_count;
       my_array_of_tbutton[ array_count ].OnClick :=
         myArrayButtonsClick;
       my_array_of_tbutton[ array_count ].Caption :=
         inttostr( array_count );
     end;
end;

procedure TForm1.myArrayButtonsClick( Sender : TObject );
begin
  Showmessage( 'You clicked # ' + inttostr((Sender as TButton).Tag));
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  define_3x3_button_array;
end;

end.