Toto je můj opsaný zatím kod

unit ping_;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, IdBaseComponent, IdComponent, IdRawBase, IdRawClient,
  IdIcmpClient, StdCtrls;

type
  TForm1 = class(TForm)
    Ping: TIdIcmpClient;
    lstReplies: TListBox;
    Edit1: TEdit;
    Button1: TButton;
    CheckBox1: TCheckBox;
    lvtrace: TListBox;
    IdIcmpClient1: TIdIcmpClient;
    procedure PingReply(ASender: TComponent;
      const AReplyStatus: TReplyStatus);
    procedure Button1Click(Sender: TObject);

    procedure CheckBox1Click(Sender: TObject);
  private
  procedure Trace;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  lstReplies:Tlistbox;
implementation

{$R *.dfm}
procedure Tform1.Trace;
var
TTL,MaxHops:integer;
Reached:boolean;
aitem:TlistItem;
begin
TTL:=0;
MaxHops:=30;
Reached:=false;
lvTrace.Items.Clear;
repeat
     inc(TTl);
     IdIcmpClient1.Host:='www.seznam.cz';
     IdIcmpClient1.TTL:=TTL;
     IdIcmpClient1.ReceiveTimeout:=5000;
     IdIcmpClient1.Ping;