Как сделать Multi Screen Emulator?

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Как сделать Multi Screen Emulator?[править | править код]

Building a multi screen emulator[править | править код]

I want to present a simple multi-screen emulator written in Delphi.

It consists in a little Form placing in the bottom-right corner of the screen, right above the traybar, which consists of 5 buttons. At the beginning the first button is down; then, when I press another button, a new fresh desktop is opened. In this new desktop I can open other programs and so on with the other buttons. When I go back to one of the buttons, I will see only the applications opened in that contest without the others.

The trick is to make the following steps just before pressing another button:

  1. Get the handles of all the visible windows (except for Desktop, Taskbar and the application itself)
  2. Hiding all the windows detecting at step 1.

After pressing the button we must:

  1. Show all the windows whose handles we got when we left the button itself by pressing another.

Of course if a button is pressed for the first time we have no handles so we will have a new fresh desktop.

I want to retrieve the handles of all the visible windows: the key is a call to the "EnumWindows" procedure passing as a parameter a callback function called for example "EnumWindowsProc".

This callback function must be of the following type:

function EnumWindowsProc(hWnd: HWND; lParam: LPARAM): Bool;

The EnumWindows function is of type:

BOOL EnumWindows(
  WNDENUMPROC lpEnumFunc, // pointer to callback function
  LPARAM lParam  // application-defined value
);

I will call EnumWindows(@EnumWindowsProc, 0);

The "EnumWindows" function loop over all windows (visible or invisible): for each window there is a call to the callback function "EnumWindowsProc" wich must be implemented. The first param "hWnd" is the handle of the current window. A possible implementation of the "EnumWindowsProc" function may be the inserting of every handle in a list. According to our target we must insert in a list the handle of the following windows:

  • Visible windows
// (IsWindowVisible(hwnd) = True)
  • Not my application window
// var processed: DWORD;
// GetWindowThreadProcessID( hwnd, @processID );
// processID <> GetCurrentProcessID
  • Not the taskbar window
// hWnd <> FindWindow('Shell_TrayWnd', Nil)
  • Not the desktop window
// hWnd <> FindWindow('Progman', Nil)


This is the code:

unit ProcessView;

interface

uses
  Windows, Dialogs, SysUtils, Classes, ShellAPI, TLHelp32, Forms;

var
  HandleList: TStringList;

function EnumWindowsProc(hWnd: HWND; lParam: lParam): Bool; stdcall;
procedure GetProcessList;

implementation

procedure GetProcessList;
var
  i: integer;
begin
  HandleList.Clear;
  EnumWindows(@EnumWindowsProc, 0);
end;

function EnumWindowsProc(hWnd: HWND; lParam: lParam): Bool;
var
  processID: DWORD;
begin
  GetWindowThreadProcessID(hwnd, @processID);
  if processID <> GetCurrentProcessID then
    if (hWnd <> FindWindow('Shell_TrayWnd', nil)) and
      (hWnd <> FindWindow('Progman', nil)) then
      if IsWindowVisible(hwnd) then
      begin
        HandleList.Add(IntToStr(HWnd));
        Result := True;
      end;
end;

initialization
  HandleList := TStringList.Create;

finalization
  HandleList.Free;
end.


In the main program I used a variable named Monitors of type "array of TstringList" whose dimension is given by the number of buttons (different monitors available) to keep in memory all the hanldes associated with every button. Another variable named CurrentMonitor keeps in memory the index of the actual monitor (the caption of the button).

This is the code:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ProcessView,
  StdCtrls, Buttons, abfComponents, Menus, ImgList, AppEvnts, TrayIcon;

type
  TForm1 = class(TForm)
    // these are the buttons (1..5) to switch from a monitor to another ///
    SpeedButton1: TSpeedButton;
    SpeedButton2: TSpeedButton;
    SpeedButton3: TSpeedButton;
    SpeedButton4: TSpeedButton;
    SpeedButton5: TSpeedButton;
    ///////////////////////////////////////////////////////////////////////

    ImageList1: TImageList; // ImageList connected to the Popup menu
    PopupMenu1: TPopupMenu; // popup menu displayed by the trayicon

    // PopupMenu Items ///////
    ShowApplication: TMenuItem; // Show the form
    HideApplication: TMenuItem; // Hide the form
    N1: TMenuItem; // -
    CloseApplication: TMenuItem; // Close the application
    ////////////////////////////////

    TrayIcon1: TTrayIcon; // my TrayIcon component; you can use yours
    procedure SpeedButton1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormShow(Sender: TObject);
    procedure ShowApplicationClick(Sender: TObject);
    // click on ShowApplication (TMenuItem)
    procedure HideApplicationClick(Sender: TObject);
    // click on HideApplication (TMenuItem)
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure CloseApplicationClick(Sender: TObject);
    // click on CloseApplication (TMenuItem)
  private
    { Private declarations }
    Monitors: array[1..5] of TStringList;
    CurrentMonitor: Integer;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.SpeedButton1Click(Sender: TObject);
var
  i: integer;
  Rect: TRect;
begin
  GetProcessList;

  Monitors[CurrentMonitor].Assign(HandleList);

  for i := 0 to HandleList.Count - 1 do
  begin
    ShowWindow(StrToInt(HandleList.Strings[i]), SW_HIDE);
  end;

  CurrentMonitor := StrToInt((Sender as TSpeedButton).Caption);
  for i := 0 to Monitors[CurrentMonitor].Count - 1 do
  begin
    ShowWindow(StrToInt(Monitors[CurrentMonitor].Strings[i]), SW_SHOW);
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i: integer;
begin
  ShowWindow(Application.Handle, SW_HIDE);
  SetWindowLong(Application.Handle,
    GWL_EXSTYLE, GetWindowLong(Application.Handle, GWL_EXSTYLE) and
    not WS_EX_APPWINDOW or WS_EX_TOOLWINDOW);
  ShowWindow(Application.Handle, SW_SHOW);

  CurrentMonitor := 1;
  for i := Low(Monitors) to High(Monitors) do
    Monitors[i] := TStringList.Create;
end;

procedure TForm1.FormDestroy(Sender: TObject);
var
  i: integer;
begin
  for i := Low(Monitors) to High(Monitors) do
    Monitors[i].Free;
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
var
  i, j: integer;
begin
  for i := Low(Monitors) to High(Monitors) do
  begin
    for j := 0 to Monitors[i].Count - 1 do
    begin
      ShowWindow(StrToInt(Monitors[i].Strings[j]), SW_SHOW);
    end;
  end;
end;

procedure TForm1.FormShow(Sender: TObject);
begin
  Height := 61;
  Width  := 173;
  Top := Screen.Height - Height - 30;
  Left := Screen.Width - Width;
end;

procedure TForm1.ShowApplicationClick(Sender: TObject);
begin
  Application.MainForm.Show;
end;

procedure TForm1.HideApplicationClick(Sender: TObject);
begin
  Application.MainForm.Hide;
end;

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
  if MessageDlg('Do you want to close Monitors?', mtConfirmation, [mbOK, mbCancel], 0) = mrCancel then
    CanClose := False;
end;

procedure TForm1.CloseApplicationClick(Sender: TObject);
begin
  Close;
end;

end.


In order to prevent multiple instances of the application I inserted some lines of code inside the project source;

this is the modified source:

program Project1;

uses
  Forms,
  Windows,
  Unit1 in 'Unit1.pas' {Form1};

{$R *.RES}

var
  atom: Integer;
begin
  if GlobalFindAtom('Monitors_Procedure_Atom') = 0 then
    atom := GlobalAddAtom('Monitors_Procedure_Atom')
  else
    Exit;

  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.Run;

  GlobalDeleteAtom(atom);
end.


The GlobalAddAtom function adds a character string to the global atom table and returns a unique value (an atom) identifying the string.

The GlobalFindAtom function searches the global atom table for the specified character string and retrieves the global atom associated with that string.

If I have already run the programm then the GlobalFindAtom function returns a value <> 0 because the atom is already present: in this case I abort the execution of the program. Instead, if the GlobalFindAtom function returns 0 then this is the first time I run the program, so I create the atom. At the end I delete the atom.

In order to remove the button on the taskbar I inserted the following code inside the OnCreate event of the form:

ShowWindow(Application.handle, SW_HIDE);
SetWindowLong(Application.handle,
              GWL_EXSTYLE,
              GetWindowLong( application.handle, GWL_EXSTYLE ) and
              not WS_EX_APPWINDOW or WS_EX_TOOLWINDOW);
ShowWindow( Application.handle, SW_SHOW );


In order to have a tray icon in the traybar (wich display a menu containing showing, hiding and closing of the form), I used a component (TTrayIcon), I built a year ago; this is the source:

unit TrayIcon;

interface

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

const
  WM_SYSTEM_TRAY_NOTIFY = WM_USER + 1;

type
  TTrayIconMessage = (imClick, imDoubleClick, imMouseDown,
    imMouseUp, imLeftClickUp, imLeftDoubleClick,
    imRightClickUp, imRightDoubleClick, imNone);

type
  TTrayIcon = class(TComponent)
  private
    { Private declarations }
    FData: TNotifyIconData;
    FIsClicked: boolean;
    FIcon: TIcon;
    FIconList: TImageList;
    FPopupMenu: TPopupMenu;
    FTimer: TTimer;
    FHint: string;
    FIconIndex: integer;
    FVisible: boolean;
    FHide: boolean;
    FAnimate: boolean;
    FAppRestore: TTrayIconMessage;
    FPopupMenuShow: TTrayIconMessage;
    FApplicationHook: TWindowHook;

    FOnMinimize: TNotifyEvent;
    FOnRestore: TNotifyEvent;
    FOnMouseMove: TMouseMoveEvent;
    FOnMouseExit: TMouseMoveEvent;
    FOnMouseEnter: TMouseMoveEvent;
    FOnClick: TNotifyEvent;
    FOnDblClick: TNotifyEvent;
    FOnMouseDown: TMouseEvent;
    FOnMouseUp: TMouseEvent;
    FOnAnimate: TNotifyEvent;
    FOnCreate: TNotifyEvent;
    FOnDestroy: TNotifyEvent;
    FOnActivate: TNotifyEvent;
    FOnDeactivate: TNotifyEvent;

    procedure SetHint(Hint: string);
    procedure SetHide(Value: boolean);
    function GetAnimateInterval: integer;
    procedure SetAnimateInterval(Value: integer);
    function GetAnimate: boolean;
    procedure SetAnimate(Value: boolean);
    procedure EndSession;

    function ShiftState: TShiftState;

  protected
    { Protected declarations }
    procedure SetVisible(Value: boolean); virtual;

    procedure DoMessage(var Message: TMessage); virtual;
    procedure DoClick; virtual;
    procedure DoDblClick; virtual;
    procedure DoMouseMove(Shift: TShiftState; X: integer; Y: integer); virtual;
    procedure DoMouseDown(Button: TMouseButton; Shift: TShiftState;
      X: integer; Y: integer); virtual;
    procedure DoMouseUp(Button: TMouseButton; Shift: TShiftState;
      X: integer; Y: integer); virtual;
    procedure DoOnAnimate(Sender: TObject); virtual;
    procedure Notification(AComponent: TComponent; Operation: TOperation); override;

    function ApplicationHookProc(var Message: TMessage): boolean;

    procedure Loaded(); override;

    property Data: TNotifyIconData read FData;

  public
    { Public declarations }
    constructor Create(Owner: TComponent); override;
    destructor Destroy; override;

    procedure Minimize(); virtual;
    procedure Restore(); virtual;
    procedure Update(); virtual;
    procedure ShowMenu(); virtual;
    procedure SetIconIndex(Value: integer); virtual;
    procedure SetDefaultIcon(); virtual;
    function GetHandle(): HWND;

  published
    { Published declarations }
    property Visible: boolean read FVisible write SetVisible default False;
    property Hint: string read FHint write SetHint;
    property PopupMenu: TPopupMenu read FPopupMenu write FPopupMenu;
    property Hide: boolean read FHide write SetHide;
    property RestoreOn: TTrayIconMessage read FAppRestore write FAppRestore;
    property PopupMenuOn: TTrayIconMessage read FPopupMenuShow write FPopupMenuShow;
    property Icons: TImageList read FIconList write FIconList;
    property IconIndex: integer read FIconIndex write SetIconIndex default 0;
    property AnimateInterval: integer read GetAnimateInterval
      write SetAnimateInterval default 1000;
    property Animate: boolean read GetAnimate write SetAnimate default False;
    property Handle: HWND read GetHandle;

    // Events
    property OnMinimize: TNotifyEvent read FOnMinimize write FOnMinimize;
    property OnRestore: TNotifyEvent read FOnRestore write FOnRestore;
    property OnClick: TNotifyEvent read FOnClick write FOnClick;
    property OnMouseEnter: TMouseMoveEvent read FOnMouseEnter write FOnMouseEnter;
    property OnMouseExit: TMouseMoveEvent read FOnMouseExit write FOnMouseExit;
    property OnMouseMove: TMouseMoveEvent read FOnMouseMove write FOnMouseMove;
    property OnMouseUp: TMouseEvent read FOnMouseUp write FOnMouseUp;
    property OnMouseDown: TMouseEvent read FOnMouseDown write FOnMouseDown;
    property OnAnimate: TNotifyEvent read FOnAnimate write FOnAnimate;
    property OnCreate: TNotifyEvent read FOnCreate write FOnCreate;
    property OnDestroy: TNotifyEvent read FOnDestroy write FOnDestroy;
    property OnActivate: TNotifyEvent read FOnActivate write FOnActivate;
    property OnDeactivate: TNotifyEvent read FOnDeactivate write FOnDeactivate;

  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents('Carlo Pasolini', [TTrayIcon]);
end;

constructor TTrayIcon.Create(Owner: TComponent);
begin
  inherited;

  FIcon := TIcon.Create();
  FTimer := TTimer.Create(nil);

  FIconIndex := 0;
  FIcon.Assign(Application.Icon);
  FAppRestore := imDoubleClick;
  FOnAnimate := DoOnAnimate;
  FPopupMenuShow := imNone;
  FVisible := False;
  FHide := True;
  FTimer.Enabled := False;
  FTimer.OnTimer := OnAnimate;
  FTimer.Interval := 1000;

  if not (csDesigning in ComponentState) then
  begin
    FillChar(FData, SizeOf(TNotifyIconData), #0);
    // memset(&FData, 0, sizeof(TNotifyIconData));
    FData.cbSize := SizeOf(TNotifyIconData);
    FData.Wnd := AllocateHWnd(DoMessage);
    FData.uID := UINT(Self);
    FData.hIcon := FIcon.Handle;
    FData.uFlags := NIF_ICON or NIF_MESSAGE;
    FData.uCallbackMessage := WM_SYSTEM_TRAY_NOTIFY;

    FApplicationHook := ApplicationHookProc;
    Update;
  end;

end;

destructor TTrayIcon.Destroy();
begin
  if not (csDesigning in ComponentState) then
  begin
    Shell_NotifyIcon(NIM_DELETE, @FData);  // booh forse @FData
    DeallocateHWnd(FData.Wnd);
  end;

  if (Assigned(FIcon)) then
    FIcon.Free;

  if (Assigned(FTimer)) then
    FTimer.Free;

  inherited;
end;

procedure TTrayIcon.Notification(AComponent: TComponent; Operation: TOperation);
begin
  inherited Notification(AComponent, Operation);

  if Operation = opRemove then
  begin
    if (AComponent = FIconList) then
      FIconList := nil
    else
    if (AComponent = FPopupMenu) then
      FPopupMenu := nil;
  end;
end;

procedure TTrayIcon.Loaded();
begin
  inherited Loaded();

  if (not Assigned(FIconList)) then
  begin
    FAnimate := False;
    FIcon.Assign(Application.Icon);
  end
  else
  begin
    FTimer.Enabled := FAnimate;
    FIconList.GetIcon(FIconIndex, FIcon);
  end;

  Update();
end;

procedure TTrayIcon.SetVisible(Value: boolean);
begin
  FVisible := Value;

  if not (csDesigning in ComponentState) then
  begin
    if FVisible then
    begin
      if (not Shell_NotifyIcon(NIM_ADD, @FData)) then
        raise EOutOfResources.Create('Cannot Create System Shell Notification Icon');

      Hide := True;
      Application.HookMainWindow(FApplicationHook);
    end

    else
    begin
      if (not Shell_NotifyIcon(NIM_DELETE, @FData)) then
        raise EOutOfResources.Create('Cannot Remove System Shell Notification Icon');

      Hide := False;
      Application.UnhookMainWindow(FApplicationHook);
    end;
  end;
end;

procedure TTrayIcon.SetHint(Hint: string);
begin
  // The new hint must be different than the previous hint and less than
  // 64 characters to be modified. 64 is an operating system limit.
  if ((FHint <> Hint) and (Length(Hint) < 64)) then
  begin
    FHint := Hint;
    StrPLCopy(FData.szTip, Hint, sizeof(FData.szTip) - 1);

    // If there is no hint then there is no tool tip.
    if (Length(Hint) <> 0) then
      FData.uFlags := FData.uFlags or NIF_TIP
    else
      FData.uFlags := FData.uFlags and (not NIF_TIP);

    Update();
  end;
end;

procedure TTrayIcon.SetHide(Value: boolean);
begin
  FHide := Value;
end;

function TTrayIcon.GetAnimateInterval(): integer;
begin
  Result := FTimer.Interval;
end;

procedure TTrayIcon.SetAnimateInterval(Value: integer);
begin
  FTimer.Interval := Value;
end;

function TTrayIcon.GetAnimate(): boolean;
begin
  Result := FAnimate;
end;

procedure TTrayIcon.SetAnimate(Value: boolean);
begin
  if (Assigned(FIconList) or (csLoading in ComponentState)) then
    FAnimate := Value;

  if (Assigned(FIconList) and (not (csDesigning in ComponentState))) then
    FTimer.Enabled := Value;
end;

procedure TTrayIcon.EndSession();
begin
  Shell_NotifyIcon(NIM_DELETE, @FData);
end;

function TTrayIcon.ShiftState(): TShiftState;
var
  Res: TShiftState;
begin
  Res := [];

  if (GetKeyState(VK_SHIFT) < 0) then
    Res := Res + [ssShift];
  if (GetKeyState(VK_CONTROL) < 0) then
    Res := Res + [ssCtrl];
  if (GetKeyState(VK_MENU) < 0) then
    Res := Res + [ssAlt];

  Result := Res;
end;

procedure TTrayIcon.DoMessage(var Message: TMessage);
var
  point: TPoint;
  shift: TShiftState;
begin

  case (Message.Msg) of
    //begin
    WM_QUERYENDSESSION:
      Message.Result := 1;
    //break;

    WM_ENDSESSION:
      EndSession();
    //break;

    WM_SYSTEM_TRAY_NOTIFY:
      case (Message.LParam) of
        //begin
        WM_MOUSEMOVE:
          if (Assigned(FOnClick)) then
          begin
            shift := ShiftState();
            GetCursorPos(point);
            DoMouseMove(shift, point.x, point.y);
          end;
        //break;

        WM_LBUTTONDOWN:
        begin
          shift := ShiftState();
          shift := shift + [ssLeft];
          GetCursorPos(point);
          DoMouseDown(mbLeft, shift, point.x, point.y);
          FIsClicked := True;
          //break;
        end;

        WM_LBUTTONUP:
        begin
          shift := ShiftState();
          shift := shift + [ssLeft];
          GetCursorPos(point);
          if (Assigned(FOnClick)) then
            DoClick();

          DoMouseUp(mbLeft, shift, point.x, point.y);

          if (FAppRestore = imLeftClickUp) then
            Restore();
          if (FPopupMenuShow = imLeftClickUp) then
            ShowMenu();
          //break;
        end;

        WM_LBUTTONDBLCLK:
        begin
          DoDblClick();

          if (FAppRestore = imLeftDoubleClick) then
            Restore();
          if (FPopupMenuShow = imLeftDoubleClick) then
            ShowMenu();
          //break;
        end;

        WM_RBUTTONDOWN:
        begin
          shift := ShiftState();
          shift := shift + [ssRight];
          GetCursorPos(point);
          DoMouseDown(mbRight, shift, point.x, point.y);
          //break;
        end;

        WM_RBUTTONUP:
        begin
          shift := ShiftState();
          shift := shift + [ssRight];
          GetCursorPos(point);

          DoMouseUp(mbRight, shift, point.x, point.y);

          if (FAppRestore = imRightClickUp) then
            Restore();
          if (FPopupMenuShow = imRightClickUp) then
            ShowMenu();
          //break;
        end;

        WM_RBUTTONDBLCLK:
        begin
          DoDblClick();

          if (FAppRestore = imRightDoubleClick) then
            Restore();
          if (FPopupMenuShow = imRightDoubleClick) then
            ShowMenu();
          //break;
        end;

        WM_MBUTTONDOWN:
        begin
          shift := ShiftState();
          shift := shift + [ssMiddle];
          GetCursorPos(point);

          DoMouseDown(mbMiddle, shift, point.x, point.y);
          //break;
        end;

        WM_MBUTTONUP:
        begin
          shift := ShiftState();
          shift := shift + [ssMiddle];
          GetCursorPos(point);
          DoMouseUp(mbMiddle, shift, point.x, point.y);
          //break;
        end;

        WM_MBUTTONDBLCLK:
          DoDblClick();
        //break;
      end;
  end;

  inherited Dispatch(Message);
end;

procedure TTrayIcon.ShowMenu();
var
  point: TPoint;
begin
  GetCursorPos(point);

  if (Screen.ActiveForm.Handle <> 0) then
    SetForegroundWindow(Screen.ActiveForm.Handle);
  FPopupMenu.Popup(point.x, point.y);
end;

procedure TTrayIcon.DoClick();
begin
  if (FAppRestore = imClick) then
    Restore();
  if (FPopupMenuShow = imClick) then
    ShowMenu();

  if (Assigned(FOnClick)) then
    FOnClick(Self);
end;

procedure TTrayIcon.DoDblClick();
begin
  if (FAppRestore = imDoubleClick) then
    Restore();
  if (FPopupMenuShow = imDoubleClick) then
    ShowMenu();

  if (Assigned(FOnDblClick)) then
    FOnDblClick(Self);
end;

procedure TTrayIcon.DoMouseMove(Shift: TShiftState; X: integer; Y: integer);
begin
  if (Assigned(FOnMouseMove)) then
    FOnMouseMove(Self, Shift, X, Y);
end;

procedure TTrayIcon.DoMouseDown(Button: TMouseButton; Shift: TShiftState;
  X: integer; Y: integer);
begin
  if (FAppRestore = imMouseDown) then
    Restore();
  if (FPopupMenuShow = imMouseDown) then
    ShowMenu();

  if (Assigned(FOnMouseDown)) then
    FOnMouseDown(Self, Button, Shift, X, Y);
end;

procedure TTrayIcon.DoMouseUp(Button: TMouseButton; Shift: TShiftState;
  X: integer; Y: integer);
begin
  if (FAppRestore = imMouseDown) then
    Restore();
  if (FPopupMenuShow = imMouseDown) then
    ShowMenu();

  if (Assigned(FOnMouseUp)) then
    FOnMouseUp(Self, Button, Shift, X, Y);
end;

procedure TTrayIcon.DoOnAnimate(Sender: TObject);
begin
  if (IconIndex < FIconList.Count) then
    Inc(FIconIndex)
  else
    FIconIndex := 0;

  SetIconIndex(FIconIndex);
  Update();
end;

procedure TTrayIcon.Minimize();
begin
  Application.Minimize();
  ShowWindow(Application.Handle, SW_HIDE);

  if (Assigned(FOnMinimize)) then
    FOnMinimize(Self);
end;

procedure TTrayIcon.Restore();
begin
  Application.Restore();
  ShowWindow(Application.Handle, SW_RESTORE);
  SetForegroundWindow(Application.Handle);

  if (Assigned(FOnRestore)) then
    FOnRestore(Self);
end;

procedure TTrayIcon.Update();
begin
  if not (csDesigning in ComponentState) then
  begin
    FData.hIcon := FIcon.Handle;

    if (Visible = True) then
      Shell_NotifyIcon(NIM_MODIFY, @FData);
  end;
end;

procedure TTrayIcon.SetIconIndex(Value: integer);
begin
  FIconIndex := Value;

  if (Assigned(FIconList)) then
    FIconList.GetIcon(FIconIndex, FIcon);

  Update();
end;

function TTrayIcon.ApplicationHookProc(var Message: TMessage): boolean;
begin
  if (Message.Msg = WM_SYSCOMMAND) then
  begin
    if (Message.WParam = SC_MINIMIZE) then
      Minimize();
    if (Message.WParam = SC_RESTORE) then
      Restore();
  end;

  Result := False;
end;

procedure TTrayIcon.SetDefaultIcon();
begin
  FIcon.Assign(Application.Icon);
  Update();
end;

function TTrayIcon.GetHandle(): HWND;
begin
  Result := FData.Wnd;
end;

end.


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Source: Взято с сайта http://www.swissdelphicenter.ch/en/tipsindex.php
ID: 01805