Re: How to determine whether any one is logged on (VB6, Win2K and later)

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

On Dec 10, 7:42 pm, "Kevin Provance" <ca...@xxxxxxxxxxx> wrote:
I had to dig for this one as I haven't used it in years...but it works. Try
this:

Option Explicit

Private Declare Function SHAppBarMessage Lib "shell32.dll" _
(ByVal dwMessage As Long, pData As APPBARDATA_TYPE) As Long

Const ABM_GETTASKBARPOS As Long = &H5

Private Type APPBARDATA_TYPE
cbSize As Long
hwnd As Long
uCallbackMessage As Long
uEdge As Long
rc As RECT
lParam As Long ' message specific
End Type

Private AppBarData As APPBARDATA_TYPE

Public Function TaskbarExists() As Boolean
AppBarData.cbSize = 36&
TaskbarExists = SHAppBarMessage(ABM_GETTASKBARPOS, AppBarData)
End Function

- Kev

"akaTwoSheds" <akaTwoSh...@xxxxxxxxx> wrote in message

news:37a93ade-a0bf-4f9b-aa08-2d802bc1f3d7@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
| On Dec 9, 3:51 pm, akaTwoSheds <akaTwoSh...@xxxxxxxxx> wrote:
| > Greetings all.
| >
| > Hopefully I can explain this in a semi-comprehensible fashion. We
| > have a VB6 application and several of our clients have recently asked
| > if it can be set up to run as a service. It's only being run on Win2K
| > or later systems so at least we don't have to worry about 9x
| > compatibility. There's a swell little freeware program called
| > XYNTService (http://www.codeproject.com/KB/system/xyntservice.aspx?
| > fid=1239&noise=3&df=90&mpp=25&sort=Position&view=Quick&fr=276) which
| > itself runs as a service and then fires the programs specified, so
| > life is good (I should add that we are working on a slightly more up
| > to date version of the application but it's no where near ready and
| > we're facing time pressure).
| >
| > Using XYNTService everything works great, the application loads up
| > when Windows starts, continues running as people log in and log out
| > and is generally perfect. The only problem is that the user interface
| > is activated by clicking an icon in the system tray. The code which
| > creates that tray icon is executed once during the program start up,
| > which, when being run by XYNTService, happens long before anyone has
| > logged in and therefore before the system tray exists.
| >
| > In otherwords, I can't make it appear when I want it to.
| >
| > It's a simple matter to run a timer every 30 or so seconds to create
| > the icon, but it gets complex when the icon has been successfully
| > added. Naturally I don't want to keep hitting that timer once the job
| > is done, but so far I've not been able to find a way to tell that the
| > tray icon has been created.
| >
| > To my mind there are two things I can check for. The existence of the
| > tray icon, or the presence of a user logged into the PC directly.
| >
| > I'm using Mark Mokoski's SysTray Module to manage the tray icon.
| > Here's the relevant code (I've eliminated the many things I've tried
| > so you can see the actual code rather than my ham handed attempts):
| >
| > ----------
| >
| > Public Declare Function ShellExecute Lib "shell32" Alias
| > "ShellExecuteA" & _
| > (ByVal hWnd As Long, & _
| > ByVal lpOperation As String, & _
| > ByVal lpFile As String, & _
| > ByVal lpParameters As String, & _
| > ByVal lpDirectory As String, & _
| > ByVal nShowCmd As Long) As Long
| >
| > Public Declare Function Shell_NotifyIcon Lib "shell32" Alias
| > "Shell_NotifyIconA" & _
| > (ByVal dwMessage As Long, & _
| > pnid As NOTIFYICONDATA) As Boolean
| >
| > Public Declare Function SetForegroundWindow Lib "user32" & _
| > (ByVal hWnd As Long) As Long
| >
| > Public Declare Function SetWindowPos Lib "user32" & _
| > (ByVal hWnd As Long, & _
| > ByVal hWndInsertAfter As Long, & _
| > ByVal x As Long, & _
| > ByVal Y As Long, & _
| > ByVal cx As Long, & _
| > ByVal cy As Long, & _
| > ByVal wFlags As Long) As Long
| >
| > Public Type NOTIFYICONDATA
| > cbSize As Long
| > hWnd As Long
| > uID As Long
| > uFlags As Long
| > uCallbackMessage As Long
| > hIcon As Long
| > szTip As String * 128
| > dwState As Long
| > dwStateMask As Long
| > szInfo As String * 256
| > uTimeout As Long
| > szInfoTitle As String * 64
| > dwInfoFlags As Long
| > End Type
| >
| > Public multiTip As Boolean 'In shell32.dll
| > ver 5, exploit "bug" and allow multi balloon tips
| > Public blnClick As Boolean
| > Public vbTray As NOTIFYICONDATA
| >
| > Public Const SWP_NOMOVE As Long = &H2
| > Public Const SWP_NOSIZE As Long = &H1
| > Public Const flags As Long = SWP_NOMOVE Or
| > SWP_NOSIZE
| > Public Const WM_RBUTTONUP As Long = &H205
| > Public Const WM_RBUTTONCLK As Long = &H204
| > Public Const WM_LBUTTONCLK As Long = &H202
| > Public Const WM_LBUTTONDBLCLK As Long = &H203
| > Public Const WM_MOUSEMOVE As Long = &H200
| > Public Const NIM_ADD As Long = &H0
| > Public Const NIM_DELETE As Long = &H2
| > Public Const NIF_ICON As Long = &H2
| > Public Const NIF_MESSAGE As Long = &H1
| > Public Const NIM_MODIFY As Long = &H1
| > Public Const NIM_SETVERSION As Long = &H4
| > Public Const NIF_TIP As Long = &H4
| > Public Const NIF_INFO As Long = &H10
| > Public Const NIS_HIDDEN As Long = &H1
| > Public Const NIS_SHAREDICON As Long = &H2
| > Public Const NIIF_NONE As Long = &H0
| > Public Const NIIF_WARNING As Long = &H2
| > Public Const NIIF_ERROR As Long = &H3
| > Public Const NIIF_INFO As Long = &H1
| > Public Const NIIF_GUID As Long = &H4 'Ver 6 of
| > Shell32.dll (WinXP SP2) only
| > Public Const HWND_NOTOPMOST As Long = -2
| > Public Const HWND_TOPMOST As Long = -1
| > Public Const NOTIFYICON_VERSION As Long = 3
| >
| > Public Sub SystrayOn(frm As Form, IconTooltipText As String)
| >
| > With vbTray
| > .cbSize = Len(vbTray)
| > .hWnd = frm.hWnd
| > .uID = vbNull
| > .uFlags = NIF_ICON Or NIF_TIP Or NIF_MESSAGE
| > .uCallbackMessage = WM_MOUSEMOVE
| > .szTip = Trim(IconTooltipText$) & vbNullChar
| > .hIcon = frm.Icon
| > End With
| > Call Shell_NotifyIcon(NIM_ADD, vbTray)
| > App.TaskVisible = False
| >
| > End Sub
| >
| > Form_Load
| >
| > Call SysTray(frmMain, "Tray Icon")
| >
| > End Sub
| > ----------
| >
| > I've tried adding a flag to indicate that the icon has been created,
| > but the code executes without an error even though there's no system
| > tray for it to put the icon in, so as far as it's concerned all is
| > swell.
| >
| > I've also tried setting and then checking the szTip, szInfo, and
| > szInfoTitle attributes hoping that when the tray became active one of
| > more of these would change, but no such luck.
| >
| > Next I tried the GetUserName API but of course that returns the user
| > name of the service which is running the application, not the name of
| > the user who's just logged into Windows. On the low tech end I also
| > tried checking the system environment variables but got the same
| > results.
| >
| > Can anyone think of a workable band aid for this? Long term the plan
| > is to separate the UI from the main portion of the program so that the
| > program can be run as a true service, and the inteface can only be
| > called up as needed but we're a far ways off from that point.
| >
| > Thanks for any ideas suggestion or at this point fervent prayers :)
|
| Thanks for all the feedback, and trust me, splitting the app into two
| distinct programs, one encapsulating the UI and another which would be
| the service is very high on the list of things to do. The trouble is
| that there's literally no way on Earth to accomplish that before the
| necessary date, hence this Rube Goldberg band aid to buy us the
| necessary time to complete the redesign.
|
| As to why it has to be a service, mostly because a new client who more
| than quadruples our business says so :) . Actually they do have a
| good reason for it. The program was specifically designed to be run
| only when a user was logged into the workstation, either locally or
| with a domain ID. The new client wants to install it on servers and/
| or work stations, neither of which will likely have anyone logged in
| most of the time.
|
| Unfortunately they also want to be able to see it before they go on
| Christmas holiday which starts on 12/21.
|
| In playing around some I've had minor success with enumerating the
| active processes and checking for "Program Manager" in the list as an
| indicator that someone has logged in. So far it seems to be working
| but I've only tested it on a handful of PCs. If anyone has a better
| band aid I'd love to hear about it.
|
| Thanks again.

Thanks Kevin, works like a champ
.

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