Disabling cyclic field based on the radio field input in a form

Hi,

I've the following code where i'm trying to get the values of 

srMfgGridForm~>useMfgGridYN~>value

srMfgGridForm~>UserGridOptions~>value

through a form. The form has got a radio field (with "Yes" & "No") and a cyclic field. How can i disable the cyclic field when "Yes" is selected by the user on the radio field?

Thanks

Ram

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procedure(srFixOffGridForm()

UseMfgGridYesNo = hiCreateGridLayout( 'UseMfgGridYesNo ;?frame "Select either one of the grids below"
?items list(
list( hiCreateLabel( ?name 'useMfgGridYNLabel ?labelText "Use Manufacturing Grid (Y/N) ? : " ) 'row 1 'col 0 )
list( hiCreateRadioField(
?name 'useMfgGridYN
?value ""
?defValue "Yes"
?choices list("Yes" "No")) 'row 1 'col 1)
list( 'col_stretch 1 1 )
))

UserGridOptions = hiCreateCyclicField(
?name 'UserGridOptions
?prompt "Custom Grid Options : "
?choices list( "" "0.01" "0.001" "0.0001" "0.00025" "0.005" "0.0005" )
?value ""
?defValue ""
?enabled t
?invisible nil
)

srMfgGridField = hiCreateFormLayout('page1 ?items list(UseMfgGridYesNo UserGridOptions) )

layout = hiCreateFormLayout(
'MyFormGridFix
?items list( srMfgGridField )
)

srMfgGridForm = hiCreateLayoutForm(
'srMfgGridForm "Fix Off Grid" layout
?unmapAfterCB nil
?initialSize '(100 100)
?callback "srFixOffGrid()"
?buttonLayout 'OKCancelDef
)

UseMfgGridYesNoValue = srMfgGridForm~>useMfgGridYN~>value
UserGridOptionsValue = srMfgGridForm~>UserGridOptions~>value

hiInstantiateForm( srMfgGridForm )
hiDisplayForm( srMfgGridForm )

);procedure

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