Locking records on sbform (Data View)

[Appollo14]

Hello,
I want to lock selected records on a subform - which is in data view -
at the moment I'am using;

Private Sub Complete_Click()
If [Complete] = True And (IsNull([Forms]![AmendOrders]![OrderItems].[Form]![InvoiceNumber])) And (IsNull([Forms]![AmendOrders]![OrderItems].[Form]![InvoiceDate])) Then
Dim Msg, Style, Title, Help, Ctxt, Response, MyString
Msg = "You Can Not Complete This Order Untill You Have Completed The ITEM INVOICE DATES/NUMBERS! All Changes To This Order Will Be Abandoned."
Style = vbOKOnly + vbWarning + vbDefaultButton1 + vbSystemModal
Title = "You Cant Do That You Muppet!!"
Help = "DEMO.HLP"
Ctxt = 1000
Response = MsgBox(Msg, Style, Title, Help, Ctxt)
If Response = vbOK Then Me.Undo ' User chose Yes.
ElseIf [Complete] = True Then
Dim Msg2, Style2, Title2, Help2, Ctxt2, Response2, MyString2
Msg2 = "If you continue this ordrer Will be Locked. Do you want to continue ?"
Style2 = vbYesNo + vbQuestion + vbDefaultButton2 + vbSystemModal
Title2 = "Set Order To Complete?"
Help2 = "DEMO.HLP"
Ctxt2 = 1000
Response = MsgBox(Msg2, Style2, Title2, Help2, Ctxt2)
If Response = vbYes Then ' User chose Yes.
Forms!AmendOrders.OrderItems.Locked = True
Else
If Response = vbNo Then Me.Undo
End If
End If
End Sub

The problem is that this locks all records and I only want it to lock selected records. The lock will be initiated by the clicking of a "Yes/No" box, which will run a couple of check and if correct criteria me will then lock the record.
I think that I should be applying this event to the CurrentRecord but I'm unsure of how to do this.
Any help greatly appreciated.
Regards,
Noel