How to hook to WH_KEYBOARD for PopupList.Window? - delphi

Question

I need to know if F11 is pressed when PopupMenu of TrayIcon is open & terminate program. Do not want RegisterHotKey. Documentation states that "PopupList.Window provides access to the Window handle of the hidden window that processes popup menu messages". So my plan is to intercept keyboard messages to that window, but instead this is what happens:
Project Project2.exe raised exception class $C0000005 with message
'access violation at 0x00020003: write of address 0x2014fd38'.
unit Unit2;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.ImgList, Vcl.Menus, Vcl.ExtCtrls;
type
TForm2 = class(TForm)
TrayIcon1: TTrayIcon;
PopupMenu1: TPopupMenu;
N11: TMenuItem;
N21: TMenuItem;
ImageList1: TImageList;
procedure PopupMenu1Popup(Sender: TObject);
private
function hook(code: Integer; w: WPARAM; p : LPARAM): Lresult stdcall;
public
{ Public declarations }
end;
var
Form2: TForm2;
HookID: hhook;
implementation
{$R *.dfm}
function TForm2.hook(code: Integer; w: WPARAM; p: LPARAM): Lresult stdcall;
begin
if code < 0 then
begin
Result := CallNextHookEx(0, code, w, p);
Exit;
end;
Result := CallNextHookEx(0, code, w, p);
end;
procedure TForm2.PopupMenu1Popup(Sender: TObject);
begin
HookID := SetWindowsHookEx(WH_KEYBOARD, #TForm2.hook, 0,
GetWindowThreadProcessId(PopupList.Window, nil));
end;
end.

Answer 1

Your hook function is a method of TForm2 and thus has an extra (hidden) self parameter passed. You should place the function outside of TForm2:
TForm2 = class(TForm)
TrayIcon1: TTrayIcon;
PopupMenu1: TPopupMenu;
N11: TMenuItem;
N21: TMenuItem;
ImageList1: TImageList;
procedure PopupMenu1Popup(Sender: TObject);
private
public
{ Public declarations }
end;
function hook(code: Integer; w: WPARAM; p : LPARAM): Lresult stdcall;
implementation
function hook(code: Integer; w: WPARAM; p: LPARAM): Lresult stdcall;
begin
if code < 0 then
begin
Result := CallNextHookEx(0, code, w, p);
Exit;
end;
Result := CallNextHookEx(0, code, w, p);
end;