Access 2013 - Update fields on form

Can you post the code you are using to do this please?
...or a small sample db would be better...

on the Pup-up form:
Private Sub Form_GotFocus()

    Me![FileSize] = GetDirOrFileSize(varPopUpFileResizeFrmPathNameTxt, varPopUpFileResizeFrmFileNameTxt)
    Me![FileSize].Requery

End Sub

Function that calcs the file size

Function GetDirOrFileSize(strFolder As String, Optional strFile As Variant) As Long

'Call Sequence: GetDirOrFileSize("drive\path"[,"filename.ext"])

   Dim lngFSize As Long, lngDSize As Long
   Dim oFO As Object
   Dim oFD As Object
   Dim OFS As Object

   lngFSize = 0
   Set OFS = CreateObject("Scripting.FileSystemObject")

   If strFolder = "" Then strFolder = ActiveWorkbook.Path
   If Right(strFolder, 1) <> "\" Then strFolder = strFolder & "\"
   'Thanks to Jean-Francois Corbett, you can use also OFS.BuildPath(strFolder, strFile)

   If OFS.FolderExists(strFolder) Then
     If Not IsMissing(strFile) Then

       If OFS.FileExists(strFolder & strFile) Then
         Set oFO = OFS.GetFile(strFolder & strFile)
         GetDirOrFileSize = oFO.Size
       End If

       Else
        Set oFD = OFS.GetFolder(strFolder)
        GetDirOrFileSize = oFD.Size
       End If

   End If

End Function

In the pop-up form there is a button that when clicked opens the acrobat file and allows the user to resize the acrobat file

How are you opening the Adobe file? If you're using a command line, you might be able to use the ShellAndWait method instead. If you can do that, then you could run your resize code AFTER the ShellAndWait method finishes.

One way to do that is shown in this link: https://support.microsoft.com/en-us/kb/99940

The relevant code is here:

Option Explicit
   Declare Function GetModuleUsage% Lib "Kernel" (ByVal hModule%)

   Function WaitShell( AppName as String)
      Dim hMod as Integer
      hMod = Shell(AppName, 1)
      If (Abs(hMod) > 32) then
         While (GetModuleUsage(hMod))
            DoEvents
         Wend
       Else
         MsgBox "Unable to start " & AppName
      End If
   End Function

Select allOpen in new window

You'd add that to a Standard Module (and make sure the Declare section is in the General Declarations section of that module), and then open your Adobe process using this syntax:

WaitShell("Your command to open the Adobe file")
<now your code to calc filesize>

Note there are many other methods to create a "ShellAndWait" process, if this one doesn't quite work as needed. A quick search for "vba shell and wait" will turn up a lot of hits.

The button that opens the PDF file is where the file path and name is Me![PathNameTxt] & Me![FileNameTxt]


Private Sub ResizeFileBtn_Click()
     application.FollowHyperlink Me![PathNameTxt] & Me![FileNameTxt]

End Sub

What I would like to do is after I close the acrobat file have the text box that shows the file size automatically update.

That's a bit of a tall order.
The code below will find a cmd.exe process and terminate it.
Adapt it to DoEvents while AcroRd32.exe exists and you can test for the existence to Acrobat Reader.
When the Reader stops, the code proceeds.

Tie it all together so that the sub that opens the Reader waits for Reader to cease and then updates things and you MAY be good.

The problem is as Jeff has come close to noting -- firing up the Reader means Access is no longer active -- so VBA processing may stop until Access is again in focus.

dim oshell
dim oWmg
dim strWndprs
dim objQResult

WScript.Sleep 100

Set oShell = CreateObject("WScript.Shell") 
Set oWmg = GetObject("winmgmts:") 

strWndprs = "select * from Win32_Process where name='cmd.exe'" 
Set objQResult = oWmg.Execquery(strWndprs) 

For Each objProcess In objQResult 

intReturn = objProcess.Terminate(1) 

Next 

Select allOpen in new window

Tried the following code and got an error Object Required at "WScript.Sleep 100"

Private Sub ResizeFileBtn_Click()
    application.FollowHyperlink Me![PathNameTxt] & Me![FileNameTxt]
     
    Dim oshell
    Dim oWmg
    Dim strWndprs
    Dim objQResult

    WScript.Sleep 100

    Set oshell = CreateObject("WScript.Shell")
    Set oWmg = GetObject("winmgmts:")

    strWndprs = "select * from Win32_Process where name='cmd.exe'"
    Set objQResult = oWmg.Execquery(strWndprs)

    For Each objProcess In objQResult

    intReturn = objProcess.Terminate(1)

Next

    Me![FileSize] = GetDirOrFileSize(Me![PathNameTxt], Me![FileNameTxt])
    Me![FileSize].Requery


End Sub

Have you tried the ShellAndWait process I suggested earlier? That would seem to be the most reliable, since you don't have to iterate anything, and immediately have a handle on the exact process you created.

You would have to change the way you open the PDF. You can use the AcroRd command line method to do that:

WaitShell "AcroRd32.exe "ThePathToYourPDF"

There are several command line args you can use with the AcroRd32.exe command. See this document (last page) for more info:

http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/Acrobat_SDK_developer_faq.pdf

I have not tried that process yet

After some more study I will give it a try this weekend

Thanks

Solution works great I thanks for your help

The only "tweek" I needed to make was to adapt the functions in the module to work with 64 bit Access - added  PtrSafe

Public Declare PtrSafe Function apiShellExecute 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
   
Public Declare PtrSafe Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)