Thanks hugely jptros, this (ignored by Adobe) bug has been annoying me for quite a while. I'd implemented a kludge to handle the tab but your solution is much better.
I had to fiddle with it a bit to get it to work for me - in case anyone else needs it, my adjusted version is pasted below.
' Until Adobe get around to fixing the bug with the Tab key, have this in a stand alone module
' When (if) it's fixed, delete the module and remove the references in the Form_Load and Form_Unload on any forms that are referencing this code
Option Compare Database
Option Explicit
' This lot are used to hook the [TAB] key on forms showing the Acrobat PDF viewer control
' because of the bug in their code that causes Access to lock up.
' http://forums.adobe.com/thread/530591?tstart=0
Public Const WH_KEYBOARD_LL = 13
Public Type KBDLLHOOKSTRUCT
vkCode As Long
scanCode As Long
flags As Long
Time As Long
dwExtraInfo As Long
End Type
Public Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Long, ByVal lpfn As Long, ByVal hmod As Long, ByVal dwThreadId As Long) As Long
Public Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Long) As Long
Public Declare Function CallNextHookEx Lib "user32" (ByVal hHook As Long, ByVal nCode As Long, wParam As Any, lParam As Any) As Long
Public Declare Function GetModuleHandle Lib "kernel32" Alias "GetModuleHandleA" (ByVal lpModuleName As Any) As Long
Public Declare Function GetActiveWindow Lib "user32.dll" () As Long
Dim gKeyboardHookHandle As Long
Public Property Get KeyboardHookHandle() As Long
KeyboardHookHandle = gKeyboardHookHandle
End Property
Public Property Let KeyboardHookHandle(val As Long)
' store the hook handle in global variable, in a control on a form, wherever you like....
End Property
Public Function KeyboardHook(ByVal nCode As Integer, wParam As Long, lParam As KBDLLHOOKSTRUCT) As Long
Dim hwnd_Form_PDFViewer As Long
' I'm only using the PDF viewer on a single form so only care about a single hwnd
If Screen.ActiveForm.Name = "frmDocumentArchive" Then hwnd_Form_PDFViewer = Screen.ActiveForm.hwnd
If nCode >= 0 Then
If lParam.vkCode = vbKeyTab And GetActiveWindow() = hwnd_Form_PDFViewer Then
Debug.Print "Aborted tab key press!"
DoEvents
KeyboardHook = 1
Exit Function
End If
End If
DoEvents
KeyboardHook = CallNextHookEx(KeyboardHookHandle, nCode, wParam, lParam)
End Function
'---- From here on, these are in the form which needs the [TAB] presses to be consumed to prevent the crash.
Private Sub Form_Load()
' Handle the Acrobat bug
KeyboardHookHandle = SetWindowsHookEx(WH_KEYBOARD_LL, AddressOf KeyboardHook, GetModuleHandle(vbNullString), 0)
End Sub
Private Sub Form_Unload(Cancel As Integer)
' Clean up after handling the Acrobat bug
UnhookWindowsHookEx KeyboardHookHandle
End Sub
