Can't Use Arguments to Call Sub When Another Procedure Running

• Microsoft Excel for Windows, versions 5.0, 5.0c
• Microsoft Excel for Windows 95, version 7.0

SYMPTOMS

If you run a Microsoft Visual Basic Programming System, Applications Edition, sub procedure that has arguments when another Visual Basic procedure is running, you may receive the following error message:

   Can't perform requested operation

CAUSE

You cannot call a Visual Basic sub procedure that has arguments if a Visual Basic procedure is running at the time. Take for example a custom dialog box with a control button assigned to a Visual Basic procedure with an argument. If you run the dialog box using the "Run Dialog" toolbar button on the Forms toolbar, you can choose the button and the procedure assigned to that button is run. However, if you show the dialog box from another Visual Basic procedure, and you click the button assigned to the procedure that has arguments, you receive the error message above, because the first Visual Basic procedure is still running. When you run the dialog box from the Visual Basic procedure, the calling procedure is suspended while the dialog box is displayed.

WORKAROUND

Although you cannot call a Visual Basic sub procedure that has arguments if a Visual Basic procedure is running, you can do either of the following:

• Call a Visual Basic subroutine that does not have arguments while a Visual Basic procedure is running

  -or-

• Model your macro code after the following example.

1. Enter the following in a new module sheet:

Sub MainMacro()
   ArgFlag = 0                           'initialize ArgFlag
   DoneFlag = 0                          'initialize DoneFlag
   DialogSheets("Dialog1").Show          'Show it initially

   'While the DoneFlag does not equal 1 (which will only occur if the
   'DoneButton is clicked), continue to loop through the Subroutine.

   Do
      If ArgFlag = 1 Then                 'if the ArgFlag is set, then
         HasArg ("Here is the Argument")  'Arg Sheet1 and
         ArgFlag = 0                      'reset the ArgFlag
         DialogSheets("Dialog1").Show     'Reshow it only after
      End If                              'having called the procedure
   Loop Until DoneFlag = 1                'that hid it
End Sub

Sub DoneButton_Click()
   DoneFlag = 1                          'set the DoneFlag
   DialogSheets("Dialog1").Hide          'hide the dialog box
End Sub

Sub ArgButton_Click()
   DoneFlag = 0                          'ensure DoneFlag set to 0
   ArgFlag = 1                         'set the ArgFlag
   DialogSheets("Dialog1").Hide          'hide the dialog box
End Sub

Sub HasArg(Arg As String)   'do not assign this macro to any button

End Sub