Shell_NotifyIcon這個API可以實現系統托盤圖示功能，然後你在自定義一下最小化的訊息就可以了，圖示功能有個例子

托盤就是在工作列右下角的小圖示。建立、更改、刪除只需要一個Windows API就能實現。這個函式叫做Shell_NotifyIcon()。這個函式和其他處理Windows 外殼的函式都包含在ShellAPI單元中。本例程在視窗建立時在工作列的右下角建立一個托盤圖示。圖示由兩個ICON交替出現。當視窗最小化時工作列中只有托盤圖示，當左鍵單擊托盤圖示視窗恢復。圖示停止交替。

unit Unit1;

interface

uses

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,SHELLAPI,

Menus, Dialogs,

ExtCtrls, ImgList;

const

MI_ICONEVENT = WM_USER + 1;

ICON_ID = 10;

type

TForm1 = class(TForm)

Timer1: TTimer;

PopupMenu2: TPopupMenu;

N1: TMenuItem;

ImageList1: TImageList;

procedure N1Click(Sender: TObject);

procedure FormCreate(Sender: TObject);

procedure FormDestroy(Sender: TObject);

procedure FormClose(Sender: TObject; var Action: TCloseAction);

procedure Timer1Timer(Sender: TObject);

private

procedure modifyicon;

procedure IconOnClick(var message: TMessage); MESSAGE MI_ICONEVENT;

procedure tranmessage(var m:TWMSYSCOMMAND); message WM_SYSCOMMAND;

public

{ Public declarations }

end;

var

Form1: TForm1;

ydic:array [0..1] of ticon;

icint:integer;

xsyc:BOOLEAN;

implementation

{$R *.DFM}

procedure TForm1.N1Click(Sender: TObject);

begin

APPLICATION.Terminate ;

end;

procedure TForm1.FormCreate(Sender: TObject);

var

IconData: TNotifyIconData;

begin

xsyc:=true;

ydic[0]:=ticon.Create;

ydic[1]:=ticon.Create;

ydic[0].Handle :=loadicon(hinstance,"icon0");//資原始檔(ICONS.RES)

ydic[1].Handle :=loadicon(hinstance,"icon1");

IconData.cbSize:=SizeOf(IconData );

IconData.Wnd:= form1.Handle;

IconData.uID:= ICON_ID;

IconData.uFlags := NIF_ICON or NIF_MESSAGE or NIF_TIP;

IconData.uCallBackMessage := MI_ICONEVENT;

IconData.hIcon :=ydic[0].Handle;

IconData.szTip := "我笑、我笑、笑笑笑";

icint:=0;

Shell_NotifyIcon( NIM_ADD, @IconData );

ShowWindow(Application.Handle, SW_HIDE );

end;

procedure TForm1.FormDestroy(Sender: TObject);

var

IconData: TNotifyIconData;

begin //解除安裝圖示

IconData.cbSize := SizeOf( IconData );

IconData.Wnd :=form1.Handle;

IconData.uID := ICON_ID;

Shell_NotifyIcon( NIM_DELETE, @IconData );

end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);

var

IconData: TNotifyIconData;

begin //解除安裝圖示

IconData.cbSize := SizeOf( IconData );

IconData.Wnd :=form1.Handle;

IconData.uID := ICON_ID;

Shell_NotifyIcon( NIM_DELETE, @IconData );

end;

procedure TForm1.Timer1Timer(Sender: TObject);

begin

modifyicon

end;

procedure TForm1.modifyicon;

var

IconData: TNotifyIconData;

begin

IconData.cbSize := SizeOf( IconData );

IconData.Wnd :=form1.Handle;

IconData.uID := ICON_ID;

icint:=(icint+1) mod 2;

IconData.uFlags := NIF_ICON or NIF_MESSAGE or NIF_TIP;

IconData.uCallBackMessage := MI_ICONEVENT;

icondata.hIcon:= ydic[icint].Handle;

IconData.szTip := "我笑、我笑、笑笑笑";

shell_notifyicon(nim_modify,@icondata);

end;

procedure TForm1.IconOnClick(var message: TMessage);

var

a:tpoint;

begin //單擊事件

if (message.lParam = WM_RBUTTONDOWN) then

begin

getcursorpos(a);

PopupMenu2.Popup(a.x,a.y);

end

else if (message.lParam = WM_LBUTTONDOWN) then

begin

timer1.Enabled:=FALSE;

if xsyc then

sendmessage(form1.Handle,wm_syscommand,sc_minimize,0)

else

begin

ShowWindow(Application.Handle,SW_RESTORE);//SW_maximize

setforegroundwindow(form1.handle);

xsyc:=true;

end;

end;

end;

procedure TForm1.tranmessage(var m: TWMSYSCOMMAND);

begin

if m.CmdType=SC_MINIMIZE then

begin

timer1.Enabled :=true;

sendmessage(Application.Handle,WM_SYSCOMMAND,SC_MINimize,0);

ShowWindow(Application.Handle, SW_HIDE );

xsyc:=false;

end

else

inherited;

end;

end.

最小化訊息過載可以這樣

procedure pgame(var msg:twmsyscommand);message wm_syscommand;

procedure Tmainfrm.pgame(var msg: twmsyscommand); //視窗最小化

begin

if msg.CmdType=SC_MINIMIZE then

begin

//處理程式碼

end;

inherited;

end;