Unable to bring form to front after calling WaitForSingleObject()

[BryanMcN]

In my vb6 program I need to use WaitForSingleObject on a separate shell launched program, kind a emulating a modal-style behavior. Now, while my vb6 app is waiting for this second program is does not re-paint, prevents the user from seeing their desktop if they wish to view it, and makes it seem as though the program has stopped responding (Which, I mean, technically it has). So I minimize the program for the brief period they're using the second program, the work flow works fine and I'm happy with that.

My problem appears once this second program has completed and I try to bring my vb6 program back up and to the front. It seems that I am unable to do so through simply maximizing the window state, BringWindowToTop(), ShowWindow(), SetWindowPos(), SetActivewindow(), SetForegroundWindow() or any combination of these. The only way I've been able to make my program come to the front is by setting it to Always On Top. I've tried looping the code until GetForegroundWindow and GetActiveWindow are the windows I expect them to be but unfortunately that doesn't seem to work. The code reports back that my program is the active window and also the foreground window but I can see that is not the case. Whatever window became active when I minimized my program is what remains in front.

My program has a MDIParent/child thing going on so I tried alternating the two of those to be the desired front form but changing that had no effect. I'm out of ideas and I really don't know why this won't work for me.

I think it's worth noting that although this problem happens the first time, subsequent launches of the secondary program have it returning just fine with no issue, which is especially frustrating. Code below.

hProcessID = Shell("""SecondProgram.exe"" print" + fileLoc, vbNormalFocus)
    
    
    If hProcessID <> 0 Then
        Call frmMDIChild.WaitForAppTerminate(hProcessID)
    End If

Public Sub WaitForAppTerminate(hProcID As Long)
   Dim hProcess As Long
   hProcess = OpenProcess(SYNCHRONIZE, 0, hProcID)

   If hProcess <> 0 Then
      frmMDIParent.WindowState = vbMinimized
      Call WaitForSingleObject(hProcess, INFINITE)
      BringWindowToTop frmMDIParent.hwnd
      ShowWindow frmMDIParent.hwnd, 3
      SetActivewindow frmMDIParent.hwnd
      SetForegroundWindow frmMDIParent.hwnd
      DoEvents
   End If

Any help or insight would be greatly appreciated!

[DataMiser]

I assume that all of those are API calls?

Have you tried simply using normal VB code

i.e. frmMdiParent.show

or
frmMDIParent.WindowState = vbNormal
frmmdiparent.setfocus

[Niya]

You should close that process handle after your WaitForSingleObject call. I don't expect it to fix your problem but that code will be leaking handles which has the potential to cause other problems.

[BryanMcN]

I'm afraid I did try those DataMiser, but saw even less functionality, with my code above I usually at least see the program come out of the tray but sitting behind the active window (If it permits it like having an explorer window opened), with .Show, or just setting the WindowState to normal it never leaves the tray and I don't see it at all.

Thanks Niya, I added that in but as you said, it didn't change my problem.

[stum]

You may use WSCript.shell to run your "secondprogram.exe" and using its inner properties to "wait" for it to close prior to continuing with the code.

Private Sub Command_Click()

    'You can use any code you want here that will be executed BEFORE secondprogram.exe will run
     Me.Enabled = False

     Dim oShell As Object
     Set oShell = CreateObject("WSCript.shell")
     oShell.run "cmd /C " & "secondprogram.exe", 0, True

    'You can use any code you want here that will be executed AFTER secondprogram.exe goes down
     Set oShell = Nothing
     Me.Enabled = True

End Sub

Let me know if this helps

[LaVolpe]

Forcing yourself to the foreground will not always work and may depend on which window is currently in the foreground and whether or not it has the keyboard focus. Here is a link (not in VB) that addresses a couple of workarounds. If you are familiar enough with APIs, the 2nd approach would be easy to convert to VB. If nothing else is working, give this a shot?

[BryanMcN]

Hi Stum, that code works fine, but allows the user to continue working in the vb6 app while the second program is open which I need to prevent.

I'll look over that information LaVolpe, it looks like it may come to that.

[stum]

Disabling the user from acting within your application should not be to hard to do.

Private Sub Command_Click()

    'You can use any code you want here that will be executed BEFORE secondprogram.exe will run
     Call DisableAllForms(True)

     Dim oShell As Object
     Set oShell = CreateObject("WSCript.shell")
     oShell.run "cmd /C " & "secondprogram.exe", 0, True

    'You can use any code you want here that will be executed AFTER secondprogram.exe goes down
     Set oShell = Nothing
     Call DisableAllForms(False)

End Sub

Public sub DisableAllForms(boolToDisable as Boolean)
    Dim frm As Form
 
    For Each frm In Forms
        If (toDisableForms = True) Then
            frm.Enabled = False
        Else
            frm.Enabled = False
        End If
    Next frm
End Sub

Or something like that.
You can also Hide all forms or, check which forms are visible, and hide only them, then retrieve visibility when app is done, you may even want to draw a big frame ontop of everything that will block the user from touching stuff, options are endless.

[Bonnie West]

My problem appears once this second program has completed and I try to bring my vb6 program back up and to the front. It seems that I am unable to do so through simply maximizing the window state, BringWindowToTop(), ShowWindow(), SetWindowPos(), SetActivewindow(), SetForegroundWindow() or any combination of these.

You may want to try a few more APIs.

[westconn1]

did you try appactivate?