unit Trayicon;
interface
uses

  SysUtils, Windows, Messages, Classes, Graphics, Controls, ShellAPI, Forms,
  menus;
const
  WM_TOOLTRAYICON = WM_USER + 1;

  WM_RESETTOOLTIP = WM_USER + 2;
type

  TTrayIcon = class(TComponent)
  private
    // BDS
    { для внутреннего пользования }
    hMapping: THandle;
    { Набор переменных }
    IconData: TNOTIFYICONDATA;
    fIcon: TIcon;
    fToolTip: string;
    fWindowHandle: HWND;
    fActive: boolean;
    fShowApp: boolean; // Добавлено
    fSendMsg: string;
    fShowDesigning: Boolean;
    { События }
    fOnClick: TNotifyEvent;
    fOnDblClick: TNotifyEvent;
    fOnRightClick: TMouseEvent;
    fPopupMenu: TPopupMenu;
    function AddIcon: boolean;
    function ModifyIcon: boolean;
    function DeleteIcon: boolean;
    procedure SetActive(Value: boolean);
    procedure SetShowApp(Value: boolean); // Добавлено
    procedure SetShowDesigning(Value: boolean);
    procedure SetIcon(Value: TIcon);
    procedure SetToolTip(Value: string);
    procedure WndProc(var msg: TMessage);
    procedure FillDataStructure;
    procedure DoRightClick(Sender: TObject);
  protected
  public
    FMessageID: DWORD;
    constructor create(aOwner: TComponent); override;
    procedure Loaded; override; // Добавлено
    destructor destroy; override;
    procedure GoToPreviousInstance;
  published
    property Active: boolean read fActive write SetActive;
    property ShowDesigning: boolean read fShowDesigning write
      SetShowDesigning;

    property Icon: TIcon read fIcon write SetIcon;
    property IDMessage: string read fSendMsg write fSendMsg;
    property ShowApp: boolean read fShowApp write SetShowApp; // Добавлено
    property ToolTip: string read fTooltip write SetToolTip;
    property OnClick: TNotifyEvent read FOnClick write FOnClick;
    property OnDblClick: TNotifyEvent read FOnDblClick write FOnDblClick;
    property OnRightClick: TMouseEvent read FOnRightClick write
      FonRightClick;

    property PopupMenu: TPopupMenu read fPopupMenu write fPopupMenu;
  end;

procedure Register;

type

  PHWND = ^HWND;

implementation

{$R TrayIcon.res}

procedure TTrayIcon.GoToPreviousInstance;
begin

  PostMessage(hwnd_Broadcast, fMessageID, 0, 0);
end;

procedure TTrayIcon.SetActive(Value: boolean);
begin

  if value <> fActive then
  begin
    fActive := Value;
    if not (csdesigning in ComponentState) then
    begin
      if Value then
      begin
        AddIcon;
      end
      else
      begin
        DeleteIcon;
      end;
    end;
  end;
end;

procedure TTrayIcon.SetShowApp(Value: boolean); // Добавлено
begin

  if value <> fShowApp then
    fShowApp := value;
  if not (csdesigning in ComponentState) then
  begin
    if Value then
    begin
      ShowWindow(Application.Handle, SW_SHOW);
    end
    else
    begin
      ShowWindow(Application.Handle, SW_HIDE);
    end;
  end;
end;

procedure TTrayIcon.SetShowDesigning(Value: boolean);
begin

  if csdesigning in ComponentState then
  begin
    if value <> fShowDesigning then
    begin
      fShowDesigning := Value;
      if Value then
      begin
        AddIcon;
      end
      else
      begin
        DeleteIcon;
      end;
    end;
  end;
end;

procedure TTrayIcon.SetIcon(Value: Ticon);
begin

  if Value <> fIcon then
  begin
    fIcon.Assign(value);
    ModifyIcon;
  end;
end;

procedure TTrayIcon.SetToolTip(Value: string);
begin

  // Данная программа ВСЕГДА переустанавливает текст подсказки и перезагружает
  // иконку. Текст может быть пустым в случае первой инициализации компонента.
  // Без инициализации иконка будет пустой и текст подсказки будет отсутствовать.
  if length(Value) > 62 then
    Value := copy(Value, 1, 62);
  fToolTip := value;
  ModifyIcon;
end;

constructor TTrayIcon.create(aOwner: Tcomponent);
begin

  inherited create(aOwner);
  FWindowHandle := AllocateHWnd(WndProc);
  FIcon := TIcon.Create;
  SetShowApp(False);
end;

destructor TTrayIcon.destroy;
begin

  // BDS
  CloseHandle(hMapping);

  if (not (csDesigning in ComponentState) and fActive)
    or ((csDesigning in ComponentState) and fShowDesigning) then
    DeleteIcon;
  FIcon.Free;
  DeAllocateHWnd(FWindowHandle);
  inherited destroy;
end;

procedure TTrayIcon.Loaded;
var

  // BDS
  // hMapping: HWND;
  tmp, tmpID: PChar;
begin

  inherited Loaded;
  if fSendMsg <> '' then
  begin
    GetMem(tmp, Length(fSendMsg) + 1);
    GetMem(tmpID, Length(fSendMsg) + 1);
    StrPCopy(tmp, fSendMsg);
    StrPCopy(tmpID, fSendMsg);
    fMessageID := RegisterWindowMessage(tmp);
    FreeMem(tmp);
    hMapping := CreateFileMapping(HWND($FFFFFFFF), nil, PAGE_READONLY, 0, 32,
      tmpID);
    if (hMapping <> NULL) and (GetLastError = ERROR_ALREADY_EXISTS) then
    begin
      if not (csDesigning in ComponentState) then
      begin
        GotoPreviousInstance;
        FreeMem(tmpID);
        halt;
      end;
    end;
    FreeMem(tmpID);
  end;
  SetShowApp(fShowApp);
end;

procedure TTrayIcon.FillDataStructure;
begin

  with IconData do
  begin
    cbSize := sizeof(TNOTIFYICONDATA);
    wnd := FWindowHandle;
    uID := 0; // определенный приложением идентификатор иконки
    uFlags := NIF_MESSAGE + NIF_ICON + NIF_TIP;
    hIcon := fIcon.Handle;
    StrPCopy(szTip, fToolTip);
    uCallbackMessage := WM_TOOLTRAYICON;
  end;
end;

function TTrayIcon.AddIcon: boolean;
begin

  FillDataStructure;
  result := Shell_NotifyIcon(NIM_ADD, @IconData);
  // По неизвестной причине, если не задан текст всплывающей
  // подсказки, иконка не выводится. Здесь это учтено.
  if fToolTip = '' then
    PostMessage(fWindowHandle, WM_RESETTOOLTIP, 0, 0);
end;

function TTrayIcon.ModifyIcon: boolean;
begin

  FillDataStructure;
  if fActive then
    result := Shell_NotifyIcon(NIM_MODIFY, @IconData)
  else
    result := True;
end;

procedure TTrayIcon.DoRightClick(Sender: TObject);
var
  MouseCo: Tpoint;
begin

  GetCursorPos(MouseCo);
  if assigned(fPopupMenu) then
  begin
    SetForegroundWindow(Application.Handle);
    Application.ProcessMessages;
    fPopupmenu.Popup(Mouseco.X, Mouseco.Y);
  end;
  if assigned(FOnRightClick) then
  begin
    FOnRightClick(self, mbRight, [], MouseCo.x, MouseCo.y);
  end;
end;

function TTrayIcon.DeleteIcon: boolean;
begin

  result := Shell_NotifyIcon(NIM_DELETE, @IconData);
end;

procedure TTrayIcon.WndProc(var msg: TMessage);
begin

  with msg do
    if (msg = WM_RESETTOOLTIP) then
      SetToolTip(fToolTip)
    else if (msg = WM_TOOLTRAYICON) then
    begin
      case lParam of
        WM_LBUTTONDBLCLK: if assigned(FOnDblClick) then
            FOnDblClick(self);
        WM_LBUTTONUP: if assigned(FOnClick) then
            FOnClick(self);
        WM_RBUTTONUP: DoRightClick(self);
      end;
    end
    else // Обработка всех сообщений с дескриптором по умолчанию
      Result := DefWindowProc(FWindowHandle, Msg, wParam, lParam);
end;

procedure Register;
begin

  RegisterComponents('Win95', [TTrayIcon]);
end;
end.