Referrencing controls from sub form to sub form with common parent

[sellert]

Greetins,
I have a form that has several tabs on it. Each tab has a different sub form. The tabs correspond to different work groups and some work groups should not be able to enter their data until another work group has populated their data. I need to referrence a control on the Material specialists form before the Quality control folks can enter data on their form. What is the best way to do this. See my code below.

If IsNull(Parent![subfrm_MRRStatus_MRRInfo].[txt_MRRNo]) Then

MsgBox "This MRR has not yet been accepted into the MRR Status database." & chr(13) & "Therefore it can not be assigned to a QC person at this time." & Chr(13) & "Notify the Material Specialist and have them Add this MRR to the system" & Chr(13) & "by clicking on the Add button in the MS Data tab.", vbOKOnly + vbCritical, "MRR NOT YET ADDED TO SYSTEM"

Exit Sub

End If

 

[sellert]

Greetings,
I was looking through other posts and found one that said to use the expression builder. Not having used it very often I didn't think about using it for this. I did and it gave me this code.

Forms![frm_MRRStatus_MainData]![subfrm_MRRStatus_MRRInfo].Form![txt_MRRNo]

This worked!!