Option Group Control: Cancel click / update event

[ironfelix717]

Hello,


I am looking to find a simpler solution to "canceling" an update/click event of an Option Group control.

The option group is used only to set a tab control's value and display the correct page in the tab control.
The option group is a series of buttons that display a tab window page.



For example....

Private Sub OpGroup_AfterUpdate()

TabCtl = OpGroup. 'show the correct page


End Sub

However, in this routine, if I want to cancel this action,
there is no way to "fully" cancel.
For example....

Private Sub OpGroup_AfterUpdate()

If SomeFunction() = true

TabCtl = OpGroup. 'show the correct page

Else

'CANCEL!
End if
End Sub

The above will obviously not switch the tab control.
However, it will still change the Option Group control's value. I would like it to not change in this case and revert or remain to its original selection, should 'SomeFunction()' be false.

The only way to simulate this behavior (that I have found) is to go back and find the original option group button, based on the tab control and re-select it. This usually is done with a loop through the option group's controls collection, which albeit small, is ineffecient.

Does anyone else have a suggestion?



Thanks

[davegri]

Check out the oldvalue property. Maybe your cancel code can set it back to that value.

[Micron]

My suggestion would be BeforeUpdate, not AfterUpdate. As a general principle, never use AfterUpdate when you want to prevent code from affecting object to which the event applies. It's too late.

[ironfelix717]

My suggestion would be BeforeUpdate, not AfterUpdate. As a general principle, never use AfterUpdate when you want to prevent code from affecting object to which the event applies. It's too late.

Hi,

Yeah, even BeforeUpdate does not afford this functionality. It's 'cancel' event argument is just as worthless as the option group's 'Old Value' property. Old Value is used in bound situations, which this is not.

Thanks

[davegri]

Try this method. Option group on_enter stores the value in a module variable.
Click another option. Typing "Reset" in the tbText will reset the option to the stored value.

Option Compare Database
Option Explicit
Dim nPrev As Integer


Private Sub OpGroup_Enter()
    nPrev = Me.OpGroup.Value
End Sub


Private Sub tbText_AfterUpdate()
    If Me.tbText = "Reset" Then
        Me.OpGroup.Value = nPrev
    End If
End Sub

[Micron]

I should have realized your frame was unbound. Post the code so we have a clue as to what the sequence/process is. There's probably a hack that can be devised using mouseup and a function.

Alternatively, you could just have a table with one field for the frame value. You wouldn't use the value as meaningful data but it would probably make the BeforeUpdate event or OldValue properties useful.

[Micron]

A frame is null when you first enter it so your module level variable should be a variant for that approach to work all the time, or you'd have to convert the null. Frame enter event could run 2 ways that I can think of:
1) if the frame and the group are the only controls that can be entered on the form (will occur on form open) or
2) if you can tab into the frame and enter it
- either case happening before an option has been selected. Otherwise I think that would work.

[moke123]

How is the value of the OG initially set? is there a default value?