const
NIF_INFO = $10;
NIM_SETVERSION = $00000004;
NOTIFYICON_VERSION = 3;
NIM_SETFOCUS = $00000003;
NIIF_INFO = $00000001;
NIIF_WARNING = $00000002;
NIIF_ERROR = $00000003;

NIN_BALLOONSHOW = WM_USER + 2;
NIN_BALLOONHIDE = WM_USER + 3;
NIN_BALLOONTIMEOUT = WM_USER + 4;
NIN_BALLOONUSERCLICK = WM_USER + 5;
NIN_SELECT = WM_USER + 0;
NINF_KEY = $1;
NIN_KEYSELECT = NIN_SELECT or NINF_KEY;
{上面列的可能不全，如果没有定义到的，可在 vs.net 中 vc7 中的 PlatformSDK/Include/ShellAPI.h 中找到}

TRAY_CALLBACK = WM_USER + $7258;

Type
PNewNotifyIconData = ^TNewNotifyIconData;

TDUMMYUNIONNAME = Record
case Integer of
0: (uTimeout: UINT);
1: (uVersion: UINT);
end;

TNewNotifyIconData = Record
cbSize: DWORD;
Wnd: HWND;
uID: UINT;
uFlags: UINT;
uCallbackMessage: UINT;
hIcon: HICON;
szTip: array [0..127] of Char;//Version 5.0为128个，以前为64个
dwState: DWORD;//Version 5.0
dwStateMask: DWORD;//Version 5.0
szInfo: array [0..255] of Char;//Version 5.0
DUMMYUNIONNAME: TDUMMYUNIONNAME;
szInfoTitle: array [0..63] of Char; //Version 5.0
dwInfoFlags: DWORD; //Version 5.0
end;

var
IconData: TNewNotifyIconData;

procedure AddSysTrayIcon;
begin
IconData.cbSize := sizeof(IconData);
IconData.Wnd := AllocateHWnd(SysTrayIconMsgHandler); //Self.Handle; {SysTrayIconMsgHandler 为后面定义的消息处理过程}
IconData.uID := 0;
IconData.uFlags := NIF_ICON or NIF_MESSAGE or NIF_TIP;
IconData.uCallbackMessage := TRAY_CALLBACK; //自定义回传消息
IconData.hIcon := Image1.Picture.Icon.Handle; //此处为一 Icon 的 Handle
IconData.szTip := 'Please send me email.';
if not Shell_NotifyIcon(NIM_ADD, @IconData) then
showmessage('add fail');
end;

procedure ShowBalloonTips;
var
TipInfo, TipTitle: string;
begin
IconData.cbSize := sizeof(IconData);
IconData.uFlags := NIF_INFO;

TipInfo := 'Please send me email.';
strPLCopy(IconData.szInfo, TipInfo, sizeof(IconData.szInfo) - 1);

IconData.DUMMYUNIONNAME.uTimeout := 3000;

TipTitle := 'Happyjoe@21cn.com';
strPLCopy(IconData.szInfoTitle, TipTitle, sizeof(IconData.szInfoTitle) - 1);

IconData.dwInfoFlags := NIIF_INFO; //NIIF_ERROR; //NIIF_WARNING;

Shell_NotifyIcon(NIM_MODIFY, @IconData);
//下面的代码实际上没有用，去掉也可以（至少目前这样认为）
IconData.DUMMYUNIONNAME.uVersion := NOTIFYICON_VERSION;
if not Shell_NotifyIcon(NIM_SETVERSION, @IconData) then
showmessage('setversion fail');
end;

procedure DeleteSysTrayIcon;
begin
DeallocateHWnd(IconData.Wnd);
if not Shell_NotifyIcon(NIM_DELETE, @IconData) then
showmessage('delete fail');
end;

procedure SysTrayIconMsgHandler(var Msg: TMessage); message TRAY_CALLBACK;

procedure SysTrayIconMsgHandler(var Msg: TMessage);
begin
case Msg.LParam of
WM_MOUSEMOVE: ;
WM_LBUTTONDOWN: ;
WM_LBUTTONUP: ;
WM_LBUTTONDBLCLK: ;
WM_RBUTTONDOWN: ;
WM_RBUTTONUP: ;
WM_RBUTTONDBLCLK: ;
//以下为新加入的消息
NIN_BALLOONSHOW: {当 Balloon Tips 弹出时执行}
showmessage('NIN_BALLOONSHOW');
NIN_BALLOONHIDE: {当 Balloon Tips 消失时执行（例如 SysTrayIcon 被删除），但指定的 TimeOut 时间到或鼠标点击 Balloon Tips 后的消失不发送此消息}
showmessage('NIN_BALLOONHIDE');
NIN_BALLOONTIMEOUT: {当 Balloon Tips 的 TimeOut 时间到时执行}
showmessage('NIN_BALLOONTIMEOUT');
NIN_BALLOONUSERCLICK: {当鼠标点击 Balloon Tips 时执行。注意：在XP下执行时 Balloon Tips 上有个关闭按钮，而且 Balloon Tips 一直显示（IconData.DUMMYUNIONNAME.uTimeout := 3000; 这句话设定的时间没有用，我的测试是这样的），如果鼠标点在按钮上将接收到 NIN_BALLOONTIMEOUT 消息。}
showmessage('NIN_BALLOONUSERCLICK');
end;
end;