Make boolean buttons mutually exclusive

I think I found the answer - hiCreateRadioField.

Will give it a try.

hiCreateRadioField works but it wasn't exactly what I need. It appeared that at least one option always had to be selected and I wanted the ability to unselect all.

Add a callback function to hiCreateBooleanButton instead of using radio field.

procedure( mutuallyExclusiveBooleans(form selButton)
  let( ()
    case(selButton
      ("Option1"
        if(form~>Options1~>value == t form~>Option2~>value = nil))
      ("Option2"
        if(form~>Option2~>value == t form~>Option1~>value = nil)))
  ) ; let
) ; procedure

The selButton option is text that is passed from the callback to indicate which button was pressed. There may be a better way to tell the function who is calling.

        hiCreateBooleanButton( ?name 'Option1
                               ?buttonText "Option1"
                               ?defValue 'nil
                               ?buttonLocation 'left
                               ?callback "mutuallyExclusiveBooleans(hiGetCurrentForm() \"Option1\")"
        ) ;Boolean
        hiCreateBooleanButton( ?name 'Option2
                               ?buttonText "Option2"
                               ?defValue 'nil
                               ?buttonLocation 'left
                               ?callback "mutuallyExclusiveBooleans(hiGetCurrentForm() \"Option2\")"
        ) ;Boolean

Not sure if this is the best way to go but it works.

You could also use a toggle field:

toggles=hiCreateToggleField(
  ?name 'toggles ?choices list(list('Option1) list('Option2) list('Option3))
  ?prompt "Choose"
  ?callback list(
    lambda((field scope item value)
      unless(boundp('MyInCallback) && MyInCallback
        let(((MyInCallback t))
          ;printf("CB: %L %L %L %L\n" field scope item value)
          foreach(toggle field->_toggleItems
            unless(eq(toggle item)
              get(field toggle)->value=nil
            )))))
      )
)
hiCreateAppForm(?name 'MyForm ?fields list(toggles))
hiDisplayForm(MyForm)

This has a callback (specified as a function object because then you find out which toggle was selected) which loops over all toggles and turns off the one that wasn't just pressed. Note that it has this dynamic variable MyInCallback to determine whether it's already in the callback because otherwise turning them off also triggers the callback again which gets a bit tricky (you'd find that you have to press the item twice to turn it on, which would be a bit strange).

Regards,

Andrew