Função (monitorar url pelo CHROME) com erro ao executar.

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unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Timer1: TTimer;
    procedure Timer1Timer(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  url : string;

implementation

{$R *.dfm}

Function GetActivePageUrlFromChrome(Handle: HWnd; Param: LParam): Bool; stdcall;
var
  List: TStrings;
  hWndChrome, hWndChromeChild: HWND;
  Buffer            : array[0..255] of Char;
begin
asm
nop
end;
  List := TStrings(Param);
  //get the window caption
  SendMessage(Handle, WM_GETTEXT, Length(Buffer), integer(@Buffer[0]));
  //look for the chrome window with "Buffer" caption
  hWndChrome := FindWindow('Chrome_WidgetWin_1', Buffer);
  if hWndChrome <> 0 then
  begin
    hWndChromeChild := FindWindowEx(hWndChrome, 0, 'Chrome_OmniboxView', nil);
    if hWndChromeChild <> 0 then
    begin
      SendMessage(hWndChromeChild, WM_GETTEXT, Length(Buffer), integer(@Buffer));
      List.Add(Buffer);
    end;
  end;
  Result := True;

end;

procedure TForm1.Timer1Timer(Sender: TObject);
var
  slChromeUrl      : TStringList;
begin
asm
nop
end;
  slChromeUrl := TStringList.Create;
  try
    EnumWindows(@GetActivePageUrlFromChrome, LParam(slChromeUrl));
    url := slChromeUrl.Strings[0];
    if url = 'http://www.devmedia.com.br' then
    begin
    {começa a fazer o desejado.}
    ShowMessage('Teste');
    end else
    if url = 'https://www.facebook.com' then
    begin
    showmessage('teste2');
    end;
  Finally
 FreeAndNil(slChromeUrl);
  end;
end;

end.

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