Toggling one column of AutoFiltering
 

I have a macro that sets different columns criteria for Autofiltering,
and I have buttons set up on the button bar to activate each macro.

What I would like to do is change the code so that each time I click
the button, that paricular criteria would either be turned on or off,
depending on it's current value. I have included a sample of one of
the macros below.

Sub Add_GreenZone()
'filter for the GREEN zone
If Not ActiveSheet.AutoFilterMode Then ' turn on autofilter if it
is off
ActiveSheet.Range("a1").AutoFilter
End If
Selection.AutoFilter Field:=8, Criteria1:="Green" ' set the
criteria
End Sub

So I think what I need it the ability to see if a particular column
has a filter applied.

Any help would be appreciated.

Mike