Probably not compose related, but how can I create...

# compose

[Se7eN]

Probably not compose related, but how can I create an immutable copy of an object from a mutable one?

class Element {
    var position: Offset by mutableStateOf(...)
    var rotation: Float by mutableStateOf(...)
    ...
}

// Then I can do this:
val element = Element(...)
element.position = newPosition

I want to pass this element object to a composable but don't want it to be mutable. I can create a similar class for an immutable element but then I'd have to update the immutable class whenever I change the Element class. Is there something else I can do?

[Zach Klippenstein (he/him) [MOD]]

Do you need immutability or just "read-only”? That is, do you need to ensure that the value you pass into the composable never ever changes, or do you just need to ensure that the composable doesn’t change the object itself?

If the latter, then you could make a read-only version of the Element interface that the mutable Element extends, and just specify that your composable takes the read-only interface.

[Se7eN]

I need to ensure the composable doesn't change the properties of Element.
Don't really understand what's the difference between immutability and read-only here 🤔
But I'll try the interface thing and see if that's what I want

[Se7eN]

Thanks, it works!

[Zach Klippenstein (he/him) [MOD]]

Read-only means that a thing doesn’t provide a way to mutate it, but it might still be mutated by someone else (e.g. List vs MutableList – a MutableList is a List, but not the other way around, so if you only have a List you can’t change it but the list can still be changed out from under you if it’s a MutableList under the hood and someone else is mutating it).

Immutable is a stronger guarantee, meaning a thing can’t change at all.