How Do I Cancel Changes on Both Main and Sub Forms Using a Single Button on Main

[Anjani]

Hello,

I have a Main Form, which also contains a SUB FORM. My SUB FORM contains Text Boxes and Check Boxes. CANCEL button on the MAIN FORM only undo's the data on the MAIN FORM. Kindly tell me a way to UNDO the changes in SUB FORM as well using the same CANCLE button on the MAIN FORM.

I tried to find an answer in the questions asked in the past, but i found it difficult to understand, as i am a rookie. Please help.

I have seen that 1st CODE Undo's all the changes in MAIN FORM.

Private Sub Cancel_Click()
On Error GoTo Err_Cancel_Click
 
Me.Undo
DoCmd.Close
 
Exit_Cancel_Click:
    Exit Sub
 
Err_Cancel_Click:
    MsgBox Err.Description
    Resume Exit_Cancel_Click
 
End Sub

And the 2nd Code is helpful to Undo the changes on subform. In the 2nd Code, "Spec" refers to the name of my SUBFORM and "Cancel" is the name of my command button on the MAIN FORM.

Private Sub Cancel_Click()
 
   On Error Resume Next
Application.Echo (False)
Me!Spec.SetFocus
DoCmd.RunCommand (acCmdUndo)
Me!Cancel.SetFocus
Application.Echo (True)
 
    DoCmd.Close
 
End Sub

Can any one please help me in getting these two codes together so that changes in MAIN FORM and SUBFORM can be done simultaneously?

Thanks in advance!!

Regards,
Anjani

[NeoPa]

See Referring to Items on a Sub-Form for some understanding, but your question is well presented (I had to merge the two halves together but a lot of good information was included anyway).

Try this :

Private Sub Cancel_Click()
    With Me
        Call .Undo
        Call .Spec.Form.Undo
    End With
    Call DoCmd.Close
End Sub

[Anjani]

Thank u sir for ur reply. When i made changes as per your code, following things happened: -

1.Changes made on MAIN FORM only and CANCEL button pressed, then changes are undone. (As per requirement)
2.Changes made on MAIN FORM and then changes made on SUB FORM. After pressing CANCEL button, none of the changes are undone. (Both the changes should be undone)
3.Changes made on SUB FORM only and pressed CANCEL, then the changes are still present on reopening of the form.(It should be undone)

Point 1 is as per requirement, but points 2 & 3 are still bugging me. Please help.Thanks

[NeoPa]

I fail to see what could possibly be going wrong with this code if your description of the situation is accurate. Maybe you could attach a copy of your database for me to check it here. See Attach Database (or other work).

[TheSmileyCoder]

First off, what you are describing is accurate, and it is working as it should. (not how you want of course, but that is a different matter)

The issue is that once you leave a form (this includes going into a subform from a main form, or into a main form from a subform) the record is SAVED.
Undo is meant to undo the changes you are in the process of making, i.e. while the form is dirty, you can reset it back to before you began the edit (but that does not include resetting the autonumber count, so even here you could argue its only a partial undo). Beyond that Access offers a single undo to the last record SAVED, PROVIDED you have NOT left the form.

So in 1) it works because you didn't leave the form.
2) The changes to main form are not undone because you left the form to go to the subform. Changes to subform are not undone because you left the subform to press the Cancel/undo button on the main form.
3) Changes are not undone because you left the subform to press the cancel button.



Now, you cannot simply undo changes to more then 1 record at a time. I have tried various approaches to this, without finding any simple method. I tried transactions once, but it seems access runs the forms within its own workspace and thus the transactions I cancelled were unaffected.


If you REALLY need this, my suggestion would be some use of temporary tables, and binding the form to the temporary tables, with update of main tables as the form is closed (or confirmed save, or similar)
While it is a fancy feature to have, I think you need to make sure this is the right place to spend your time at the moment, or if you should focus your energy on another part of your design.

[NeoPa]

Thank you Smiley :-) That is the rationale that I couldn't find. Of course you're quite correct and I simply overlooked what I should have known.

@Anjani.
You can stop any data from being saved (until you are ready for it - presumably with a button on your form), but if you do so, then the cursor stays where it was and doesn't leave the form. You absolutely can't work on main and sub record areas at the same time (IE. leaving outstanding work).