[Resolved] ShellExcecute - wait

[Bruce Fox]

Good Morning (Night) all,

I want to set the mouse to 'HourGlass' until ShellExcecute has
loaded the appropriate app and file, then I want to set the mouse back to 'Default' (I know the sytax etc for the mouse).

So, what I'm after is the Return, from that API call, to determine the app has loaded. - I guess something similar to SendKeys [wait]

ShellExecute Me.hwnd, vbNullString, sPathName, vbNullString, "C:\", SW_SHOWNORMAL

Regards,
Bruce.

[technitaes]

Here's a ShellWait that I use sometimes for similiar situations...

Private Type STARTUPINFO
    cb As Long
    lpReserved As String
    lpDesktop As String
    lpTitle As String
    dwX As Long
    dwY As Long
    dwXSize As Long
    dwYSize As Long
    dwXCountChars As Long
    dwYCountChars As Long
    dwFillAttribute As Long
    dwFlags As Long
    wShowWindow As Integer
    cbReserved2 As Integer
    lpReserved2 As Long
    hStdInput As Long
    hStdOutput As Long
    hStdError As Long
End Type
Private Type PROCESS_INFORMATION
    hProcess As Long
    hThread As Long
    dwProcessID As Long
    dwThreadID As Long
End Type
 
Private Declare Function WaitForSingleObject Lib "kernel32" (ByVal _
    hHandle As Long, ByVal dwMilliseconds As Long) As Long
 
Private Declare Function CreateProcessA Lib "kernel32" (ByVal _
    lpApplicationName As Long, ByVal lpCommandLine As String, ByVal _
    lpProcessAttributes As Long, ByVal lpThreadAttributes As Long, _
    ByVal bInheritHandles As Long, ByVal dwCreationFlags As Long, _
    ByVal lpEnvironment As Long, ByVal lpCurrentDirectory As Long, _
    lpStartupInfo As STARTUPINFO, lpProcessInformation As _
    PROCESS_INFORMATION) As Long
 
Private Declare Function CloseHandle Lib "kernel32" (ByVal _
    hObject As Long) As Long
 
Public Function ShellWait(Pathname As String, Optional WindowStyle As Long)
    Dim proc As PROCESS_INFORMATION
    Dim start As STARTUPINFO
    Dim ret As Long
    ' Initialize the STARTUPINFO structure:
    With start
        .cb = Len(start)
        If Not IsMissing(WindowStyle) Then
            .dwFlags = &H1
            .wShowWindow = WindowStyle
        End If
    End With
    ' Start the shelled application:
    ret& = CreateProcessA(0&, Pathname, 0&, 0&, 1&, _
            &H20&, 0&, 0&, start, proc)
    ' Wait for the shelled application to finish:
    ret& = WaitForSingleObject(proc.hProcess, -1&)
    ret& = CloseHandle(proc.hProcess)
End Function

Hope it helps

[Bruce Fox]

Thanks for the reply technitaes,

I was hoping for something less intense


Cheers,
Bruce.

[jim mcnamara]

That's the standard way to do a 'shell and wait', it's in MSDN this way.

ShellExecute and ShellExecuteEx don't allow you to wait on process termination of the shelled process.

[Bruce Fox]

Thanks Jim,

I kinda figured that'd be the case, I'm just plugging it into a Module now


Regards,
Bruce.

[technitaes]

Well, the thing about it is you can copy and past this into a module, save it as something like "modShellWait.bas", copy it to a back up directory, then copy it into any programs you write in the future that need the functionality, and all you need to do at that point is call the public function ...

MousePointer = vbHourglass
ShellWait "C:\SomeDir\SomeFile.bat"
MousePointer = vbDefault

[Bruce Fox]

Yep, thats what I've done

Thanks again for your time. Just testing it now.


Bruce.

[Bruce Fox]

Hmmmm,

Dosn't seem to be working.

I can hear the CD run up (thats where the source file is), however,
there never is an instance of the associated app!


I have steped thru the API to no avail


I'm using:

Call modStartApp.ShellWait(sPathName)

Running on Windows 2000

[technitaes]

Hmmm...

What OS are you running? I haven't tested it on any machines beyond 98SE/ME. I think we're running an app that's using it on an NT box, but I'd have to double check to be sure.

As you can tell, we're a little behind in updating our machines. The new bells and whistles haven't appeared cost effective as of yet.

[Bruce Fox]

Win 2000 (in an Access 2000 db VBA).

[technitaes]

Well, it could be the Win2k or it could be the Access db. I've only run it in VB6 apps on the afore mentioned OS's.

Wait...
I remember my boss having a little trouble with an app he was using this in. He's out today, but I can check with him tomorrow and see if he remembers what it was and how he fixed it. Just so I'll know for reference, is the app you calling a Windows GUI program, some kind of batch file/dos file, or something else?

[Bruce Fox]

The files range from .txt, pdf, .jpg's etc.

I have the file (path) and FileName listed in a Recorset, the user
can dblClick on the FileName and have the file open with its associated
application. (The ShellExcecute worked well, however, I was
adding the Hourgalss as a user prompt etc as previously discussed).

Thanks again technitaes.



Bruce.

[Joacim Andersson]

There shouldn't be any problems running the code on Win2k. The problem is the following part of the code:

If Not IsMissing(WindowStyle) Then
            .dwFlags = &H1
            .wShowWindow = WindowStyle
        End If

Since WindowStyle is declared as an optional Long argument it is never missing. The IsMissing can only be used with Variants. If you don't pass a value to WindowStyle the default value will be 0 which is the same as vbHide. So the code is executing the shelled app but the window is hidden. Try using this call instead:

Call modStartApp.ShellWait(sPathName, vbNormalFocus)

But as I have understood your original question you just want to show the hourglass while the shelled application is loading. This code will stop the execution of your application until the shelled application is closed.

Best regards

[Bruce Fox]

Ahhh...

Thanks Joacim, Correct - I don't want to wait till the opened app is closed....


(For what its worth, I had set the WindowStyle to no avail)

To re-ittereate I need the Hourglass just for the duration the
(associated) app is loading.


Regards to All Con

[Bruce Fox]

*Thought* Can I ShellExcecute, capture the Hwnd and then use
an API to monitor the Hwnd till it's loaded (checking in a Do-Loop).


Bruce.

[Bruce Fox]

Ideas?

[Bruce Fox]

*Fummp*

[technitaes]

Bruce,

Sorry I misunderstood exactly what you were trying to accomplish. You can use your loop idea though, to check for the loading of another program by using the FindWindow API.

'Module General Declarations
Declare Function FindWindow Lib "User" (ByVal lpClassName As Any, ByVal lpWindowName As Any) As Integer
'Same Module
Public Function ApplicationLoaded(ByVal Title As String) As Boolean
  Dim intWindowHandle As Integer
  
  intWindowHandle = FindWindow(0&, Title)
  ApplicationLoaded = (intWindowHandle <> 0)
End Function
'
'Some Form ...
MousePointer = vbHourglass
Shell "Notepad.exe"
Do While Not ApplicationLoaded("Untitled - NotePad")
  Me.Refresh
Loop
MousePointer = vbDefault

[Bruce Fox]

technitaes,

Thanks again for your response.

That was the approach I've been playing with. However, I must use
ShellExcecute as I'm not sure what the app will be.

Having said that, I can't use that method with that ApplicationLoaded API.

So, I'm stuck now trying to incorporate an API that can give me that hwnd of the ShellExec app, and loop until that has loaded.

Again, appreciate your help

Bruce.

[Bruce Fox]

ideas, thoughts?

[Shawn N]

How exactly can you tell when a program is done loading?

I'm assuming that it's different app everytime so you can't wait for the splash screen since not all will definetley have one.

[vbud]

hmmm...see this thread, try the code I mentionned and tell me how it goes...

http://www.vbforums.com/showthread.p...47#post1258647

[Bruce Fox]

Thanks Vbud, But that too looks like it waits till the (opened) app closes...

Regards,
Bruce.

[technitaes]

Hey Bruce,

I just had a thought. If you're Shelling these files out to a normal window, the new app should take system focus away from you program. You might simply try setting the MousePointer to an hourglass before the shell call, then use the Form_LostFocus event to return the MousePointer to default.

You'd need to test it out a fair bit, and probably put in some safety checks (like turning the hourglass off when a certain control is clicked or when a function key [F5?] is pressed or something). It might just do the trick though and you could forget worrying about all the API business.

Just a thought...

[Joacim Andersson]

Originally posted by technitaes
I just had a thought. If you're Shelling these files out to a normal window, the new app should take system focus away from you program. You might simply try setting the MousePointer to an hourglass before the shell call, then use the Form_LostFocus event to return the MousePointer to default.

Pretty good idea, except that VB doesn't raise the Form_LostFocus event when another application gets focus

[technitaes]

Originally posted by Joacim Andersson
Pretty good idea, except that VB doesn't raise the Form_LostFocus event when another application gets focus

Ahh Yes, Joacim Andersson. What a bummer... VB doesn't quite do what you'd expect it to all the time now does it!

So OK. Bruce, this has just about got me fed up! I hate it when I know something MUST be possible, but I just can't seem to solve it. So try this...

'In a modules General Declarations...
Public Declare Function GetActiveWindow Lib "user32" () As Long
Public Declare Function ShellExecute Lib "shell32.dll" 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
 
'In the click/dblclick event you're writing...
    Dim lhWnd As Long
    
    lhWnd = GetActiveWindow()    'Should be the same as Me.hWnd
    MousePointer = vbHourglass
    ShellExecute Me.hWnd, vbNullString, sFileName, vbNullString, sDefDir, vbNormalFocus
    Do While lhWnd = GetActiveWindow()
        DoEvents
    Loop
    MousePointer = vbDefault

Since the first call to GetActiveWindow() actually returns the same value as Me.hWnd, you could forego the lhWnd variable and shorten the code to ...

'in the click/dblclick event...
    MousePointer = vbHourglass
    ShellExecute Me.hWnd, vbNullString, sFileName, vbNullString, sDefDir, vbNormalFocus
    Do While Me.hWnd = GetActiveWindow()
        DoEvents
    Loop
    MousePointer = vbDefault

Disclaimer, if the user selects another application while waiting on the shelled program to load then the Hourglass will return to default. Likewise if the program associated with the file has a splash screen, as soon as it appears (and thus becomes the active window) then the Hourglass will return to default.

I've actually tested this!

Hope it helps!

[Bruce Fox]

Legendary


Thanks technitaes for ALL your efforts, much appreciated.

This is the winning combination - Inital testing going well..

Screen.MousePointer = vbHourglass
    ShellExecute Me.hWnd, vbNullString, sFileName, vbNullString, sDefDir, vbNormalFocus
    Do While Me.hWnd = GetActiveWindow()
        DoEvents
    Loop
  Screen.MousePointer = vbDefault

Regards,
Bruce.

[Aaron Young]

You could utilize the WaitForInputIdle() API, i.e.

Option Explicit
 
Private Type SHELLEXECUTEINFO
  cbSize As Long
  fMask As Long
  hwnd As Long
  lpVerb As String
  lpFile As String
  lpParameters As String
  lpDirectory As String
  nShow As Long
  hInstApp As Long
  lpIDList As Long
  lpClass As String
  hkeyClass As Long
  dwHotKey As Long
  hIcon As Long
  hProcess As Long
End Type
 
Private Declare Function ShellExecuteEx Lib "shell32.dll" (lpExecInfo As SHELLEXECUTEINFO) As Long
Private Declare Function WaitForInputIdle Lib "user32" (ByVal hProcess As Long, ByVal dwMilliseconds As Long) As Long
 
Private Const SEE_MASK_NOCLOSEPROCESS = &H40
 
Public Sub ShellWait(ByVal sFile As String)
  Dim tSEI As SHELLEXECUTEINFO
  Dim lResult As Long
     
  With tSEI
    .fMask = SEE_MASK_NOCLOSEPROCESS
    .lpFile = sFile
    .lpVerb = "OPEN"
    .nShow = 1
    .cbSize = Len(tSEI)
  End With
  ' Launch the File in with it's associated application (if applicable.)
  Call ShellExecuteEx(tSEI)
  
  ' Wait for the application to Idle (Finish Loading.)
  Do
    lResult = WaitForInputIdle(tSEI.hProcess, 10)
    DoEvents
  Loop While lResult <> 0
End Sub

[Bruce Fox]

Thanks Aaron,

Looks like a few ideas are begining to surface now

I was surprised that I had difficulty finding (via Search) similar posts.



Regards,
Bruce.

[Bruce Fox]

Feedback.

Not too sure if this is working as expected

Option Explicit
 
Private Declare Function ShellExecute Lib "shell32.dll" 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
 
Private Declare Function GetActiveWindow Lib "user32" () As Long
 
Const SW_SHOWNORMAL = 1
 
Private Sub Command0_Click()
 
Debug.Print Me.hwnd & vbTab & GetActiveWindow()
 
        ShellExecute Me.hwnd, vbNullString, "D:\COSYS RMN.jpg", vbNullString, "C:\", vbMinimizedNoFocus 'SW_SHOWNORMAL
 
Debug.Print Me.hwnd & vbTab & GetActiveWindow()
        
        Do While Me.hwnd = GetActiveWindow()
 
Debug.Print Me.hwnd & vbTab & GetActiveWindow()
            DoEvents
        
        Loop
 
End Sub

[Bruce Fox]

Aaron,

That example seems to work well.

technitaes: GetActiveWindow() never seems to be the same
as the Me.Hwnd? (Hence, bypassing the Do.. While)


Again, Thanks guys.
Bruce.

[technitaes]

Bruce,
Sorry it didn't seem to work for you. I tried out both of the pieces of code I posted, and it worked every time (used a call to an .exe, .txt, .htm, and .gif all of which obviously use different programs to load). Not sure what the difference might have been.

Aaron,
Sweet! Glad someone was able to come up with a solution that would work for Bruce.

[Bruce Fox]

technitaes,

In an app like Access, with sub forms etc, you need to use Application.hWndAccessApp instead of Me.Hwnd!

That was the problem...

It now works well



So, many thanks for your time.

It looks like we now have two methods to acheive this goal!


Thanks again,

Regards,
Bruce.