{$APPTYPE GUI}
{$MODE DELPHI}
program WinHello;

uses
  Strings, Windows, ShellApi;

const
  AppName   = 'WinHello';
  menu_Tray = 95;

  MainWindowStyle = WS_CAPTION or WS_BORDER or WS_SYSMENU;
  WM_TRAYICON     = WM_USER + $0001;

var
  TrayIcon: NotifyIconData;


function IntToStr (l: LONGINT): STRING;
begin
  Str (l, result);
end;


var
  r : TRect;
  br: HBrush;
  NID : TNotifyIconData;

function WindowProc(Wnd: HWnd; msg, WParam,
                    LParam: Longint): Longint; stdcall; export;

var
  dc : hdc;
  ps : paintstruct;

begin
  result := 0;

  case msg of

    WM_PAINT:
      begin
        DC := BeginPaint(wnd, ps);
        GetClientRect (wnd, @r);
        br := CreateSolidBrush($0000FF);
        FillRect (dc, r, br);
        DeleteObject(br);
        EndPaint(wnd, ps);
        Exit;
      end;


    WM_TRAYICON:
      begin
        Exit;
      end;

    WM_CLOSE:
      begin
         PostQuitMessage(0);
         Exit;
      end;
  end;

  result := DefWindowProc(Wnd, msg, WParam, LParam);
end;

 { Register the Window Class }
function WinRegister: Boolean;
var
  WindowClass: WndClass;
begin
  WindowClass.Style := cs_hRedraw or cs_vRedraw;
  WindowClass.lpfnWndProc := WndProc(@WindowProc);
  WindowClass.cbClsExtra := 0;
  WindowClass.cbWndExtra := 0;
  WindowClass.hInstance := system.MainInstance;
  WindowClass.hIcon := LoadIcon(0, idi_Exclamation);
  WindowClass.hCursor := LoadCursor(0, idc_Arrow);
  WindowClass.hbrBackground := GetStockObject(WHITE_BRUSH);
  WindowClass.lpszMenuName := nil;
  WindowClass.lpszClassName := AppName;

  Result := RegisterClass(WindowClass) <> 0;
end;

 { Create the Window Class }
function WinCreate: HWnd;
var
  hWindow: HWnd;
begin
  hWindow := CreateWindowEx(WS_EX_TOOLWINDOW, AppName,
             'Hello Bokul', MainWindowStyle,
             r.Left, r.Top, r.Right, r.Bottom, 0, 0,
             system.MainInstance, nil);

  if longint(hWindow) = 0 then begin
    MessageBox(0, 'WinCreate failed', nil, mb_Ok);
    Exit;
  end;

  ZeroMemory (@TrayIcon, SizeOf (TrayIcon));
  TrayIcon.cbSize := SizeOf (TrayIcon);
  TrayIcon.hWnd := hWindow;
  TrayIcon.uID := 1;
  TrayIcon.uFlags := NIF_TIP or NIF_ICON or NIF_MESSAGE;
  TrayIcon.uCallbackMessage := WM_TRAYICON;
  TrayIcon.hIcon := LoadIcon(0, idi_Exclamation);
    // LoadIcon (0, IDI_WINLOGO);
  TrayIcon.szTip := 'My tray Icon';
  Shell_NotifyIcon (NIM_ADD, PNotifyIconData(@TrayIcon));


  ShowWindow(hWindow, CmdShow);
  UpdateWindow(hWindow);

  Result := hWindow;
end;


var
  AMessage: Msg;
  hMainWindow: HWnd;

begin

  br := CreateSolidBrush($000000);

  if not WinRegister then begin
    MessageBox (0, PChar('Can not register window class. Error code ' + IntToStr (GetLastError)),
                'Error', MB_OK or MB_ICONERROR);
    DeleteObject (br);
  end;

  r.Right := 200;
  r.Bottom := 100;
  r.Left := GetSystemMetrics (SM_CXSCREEN) div 2 - r.Right div 2;
  r.Top := GetSystemMetrics (SM_CYSCREEN) div 2 - r.Bottom div 2;
  AdjustWindowRectEx(r, MainWindowStyle, FALSE, WS_EX_TOOLWINDOW);



  hMainWindow := WinCreate;
  while GetMessage(@AMessage, 0, 0, 0) do begin
    TranslateMessage(AMessage);
    DispatchMessage(AMessage);
  end;
  Shell_NotifyIcon (NIM_DELETE, PNotifyIconData(@TrayIcon));
  Halt(AMessage.wParam);
end.