系统托盘上下文菜单不消失

我创建通知图标时使用:

notifyIcon.cbSize = sizeof(NOTIFYICONDATA);
notifyIcon.hWnd   = mainWnd;
notifyIcon.uID    = 100;
notifyIcon.uFlags = NIF_ICON | NIF_TIP | NIF_MESSAGE;
notifyIcon.hIcon  = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_LOGO));
notifyIcon.dwState = NIS_SHAREDICON;
notifyIcon.uVersion = NOTIFYICON_VERSION;
notifyIcon.uTimeout = 15000;
notifyIcon.uCallbackMessage = APP_MSG_TRAY;
wcscpy_s(notifyIcon.szTip, 127, WTXT_APP_TRAY_TOOLTIP);

Shell_NotifyIcon(NIM_ADD, &notifyIcon);
Shell_NotifyIcon(NIM_SETVERSION, &notifyIcon);

在wm_ButtonDown和wm_ContextMenu上弹出一个上下文菜单,如下所示:

MENUITEMINFO separatorBtn = {0};
separatorBtn.cbSize = sizeof(MENUITEMINFO);
separatorBtn.fMask = MIIM_FTYPE;
separatorBtn.fType = MFT_SEPARATOR;

HMENU hMenu = CreatePopupMenu();

if(hMenu) {
 InsertMenu(hMenu, -1, MF_BYPOSITION, APP_OPEN_OPTIONS, WTXT_OPTIONS);
 InsertMenuItem(hMenu, -1, FALSE, &separatorBtn);
 InsertMenu(hMenu, -1, MF_BYPOSITION, APP_MSG_EXIT, WTXT_EXIT);

 POINT pt;
 GetCursorPos(&pt);
 SetForegroundWindow(mainWnd);
 TrackPopupMenu(hMenu, TPM_RIGHTBUTTON, pt.x, pt.y, 0, mainWnd, NULL);
 PostMessage(mainWnd, WM_NULL, 0, 0);
 DestroyMenu(hMenu);
}

它工作得很好,但是上下文菜单并不总是消失。有时(通常)如果系统托盘中有IE.Winamp和我的应用程序图标,如果随后右键单击“我的应用程序”和“Winamp”,Bot菜单将出现,只有单击某个项目,我的菜单才会自动消失。

有什么想法吗?

谢谢。。。