Lars you can limit the # of selected choices in a multiple choice.

RoSoft_Steven Rooryck Thanks for the hint - I checked that and didn't find anything in the configuration of the field. I guess you can manually (script) limit the number, but that is what I'd call very difficult. Can you please tell me, how to limit the number of selected choices?

Lars Hi, I'm in the middle of working this out for you. As you say, it's not simple. I should have a solution for you before the end of the weekend!

John Halls Lars It is actually not that difficult. If you want to limit the choices to 2 you can add this in the Writable if setting of the multiple choice field: cnt(chosen('M ChoiceField')) < 2

You also need a button to clear the selections if you've reached the limit as you can't change selections in the MCFielf anymore : MChoiceField := 0

https://forum.ninox.com/t/p8hrt87

https://forum.ninox.com/t/p8hrth0

https://forum.ninox.com/t/g9hrzlf/filling-lines-of-ordersarticles-with-dynamic-multiple-choice-fields-and-cascading-dynamic-choice-fields

Are some treads about multiple choice fields.

Steven

RoSoft_Steven Rooryck Lars

I had in mind a Trigger on update: on the MCF that would only allow 2 choices and any attempt to add a third would revert the MCF to its original value. Only when one or both of the two are removed can alternative choices be made.

This solution requires a text field to store the current hex value of the MCF.

Thanks to Alain Fontaine for his excellent explanation of how the hex value of a MCF is calculated here  https://forum.ninox.com/t/83hrts2

I have added a text field and called it MultipleChoiceHexValue, and in the Trigger on update: of your MCF put this code

let MULTIARRAY := numbers(MultipleChoiceField);
if count(MULTIARRAY) > 2 then
    MultipleChoiceField := MultipleChoiceHexValue
else
    let BLOCKCOUNT := floor((max(MULTIARRAY) - 0.5) / 4) + 1;
    let HEXKEY := "0123456789ABCDEF";
    let hexString := "";
    for blockCounter in range(0, BLOCKCOUNT) do
        let hexBlock := 0;
        for blockPosition in range(1, 5) do
            for multiCounter in range(0, count(MULTIARRAY)) do
                if item(MULTIARRAY, multiCounter) = blockCounter * 4 + blockPosition then
                    hexBlock := hexBlock + pow(2, blockPosition - 1)
                end
            end
        end;
        hexString := hexString + substr(HEXKEY, hexBlock, 1)
    end;
    MultipleChoiceHexValue := hexString
end

Regards John

Having just posted the above after a few hours working the code out, I thought I'd read all of that post and now realise that my code can be replace with

if count(numbers(MultipleChoiceField)) > 2 then
    MultipleChoiceField := MultipleChoiceHexValue
else
    MultipleChoiceHexValue := raw(MultipleChoiceField)
end

Still, I enjoyed the challenge...

John Halls Not a one-liner yet, but close .