Question about shared state in Android iOS MPP I have a work

Question

Question about shared state in Android iOS MPP I have a working setup with compilation to Android and iOS but now I have run into the whole frozen state world new to me and is stuck after some hours of trawling the web for info and examples Simplified I have a static global variable CurrentConfig which points to the current version of a parsed JSON config This is used in many places of the app so they should not load and parse it all the time on their own but share it Once in a while the config is replaced with a freshly downloaded one on the fly I guess this is an often seen pattern but I have no idea how to solve it using Kotlin Native Anyone have a best practice example to accomplish something like this

Olenyov Kirill · Answer

The same situation looking for some common caching solutions

Piasy · Answer

In Android you don t need to freeze it so no special care is needed In iOS you must freeze it then you can use `AtomicReference` and call `compareAndSet` when you want to update it

Olenyov Kirill · Answer

Is there any kind of ConcurrentHashMap for K N

Piasy · Answer

I think there isn t

Henrik · Answer

Thanks Piasy Do I need to add some kind of reference or library to Gradle to use AtomicReference I can t resolve it And can I use it on all platforms The code is a shared library so it would be nice if it worked in Android too

Piasy · Answer

You don t need `AtomicReference` can only be accessed in Kotlin Native

Henrik · Answer

OK thanks Will look into it and give it a go

Henrik · Answer

I keep getting `Unresolved reference AtomicReference` even if I only use it in iOS specific code and build for IosX64 `val testRef = AtomicReference someData `

Piasy · Answer

Do you add `import kotlin native concurrent AtomicReference`

Henrik · Answer

Argh sorry I have been spending too much time with C lately so I only had `import kotlin native concurrent` That seems to do the trick thank you again

kpgalligan · Answer

There are multiple options for caches Check out <https github com touchlab Stately>

kpgalligan · Answer

There s a common definition of AtomicReference as well as a concurrent hash map although I m rewriting that because the implementation isn t really performant rewriting right now actually

kpgalligan · Answer

For a simple parsed json cache either AtomicReference or if you know all reads will happen on say the main thread you could mark the object ThreadLocal

kpgalligan · Answer

See and for more info

Henrik · Answer

Thanks Kevin And thanks for some of your well explained online articles as well Very useful information all of it slightly smiling face I considered `ThreadLocal` but I don t think it is the right fit in this context

kpgalligan · Answer

Yeah you need to be careful with it and if you re not quite sure of thread context it ll be bad

Henrik · Answer

Quick question to help my understanding If an `AtomicReference` is used as a private variable inside a frozen class will it then be frozen too so that I cannot update it using `compareAndSet`