I saw this on reddit I didn t know kotlinx synthetic is no l

Question

I saw this on reddit I didn t know kotlinx synthetic is no longer recommended practice Does anyone know why it is no longer recomended <https android review googlesource com c platform frameworks support + 882241>

antonis · Answer

That was a selling point for jumping to Kotlin a few months ago Is this official FindviewById was never actually used anyway usually libraries did the job

antonis · Answer

Probably it s just a coding practice for the sample code I guess

Ema · Answer

Ok this is actually a relief I was thinking I was the only one having issue with that

Ema · Answer

when i started with kotlin and synthetics I have bunch of issues with that Problem is you can only use them AFTER `onCreateView` and the references you get are actually nullable escaping the type system of kotlin This happened to me especially when you need a ref to one view in a onScrollChange listener of some sort that you set up in onCreateView Depending on device and use case you may have a nullpointer or not not even deterministic confused

ghedeon · Answer

you scared the shit out of me guys Maybe they need different requirements for their libs but not recommend practice is a bit of a stretch for this PR < Hadi Tok> Why would you word your question like they officially against it Seems like a clickbait

ghedeon · Answer

P S never had issues with synthetics They are awesome Plus `LayoutContainer` +1

Hadi Tok · Answer

sorry I was being sarcastic

Saiedmomen · Answer

I had issues with it too but they were minor and once you get how to work with them It is great

Ema · Answer

I don t think they can stay as they are Synthetic return non nullable types while actually in some cases they are nullable

antonis · Answer

Are those issues tackled with findviewbyid or butterknife dagger etc

antonis · Answer

I tend to use lateinit with non nullable type for view elements anyway I m not sure if its

antonis · Answer

the best practice but it makes the code cleaner

dknapp · Answer

The conversation around this PR on reddit mentioned that they don t cache when used in viewholderes unless you do a little extra work and it s not beginner friendly

Allan Wang · Answer

Link to the reddit post for those who are interested <https www reddit com r androiddev comments ala9p2 why kotlinx synthetic is no longer a recommended > Modularity seemed to be a big topic as well since you can t use synthetics for view in a separate module

Jirka · Answer

This is just an internal note for Google s project where they are most likely to use their own horrible stuff like LiveData DataBinding etc

Jirka · Answer

It doesn t really tell the community not to use synthetics they are pretty much beware of saying thinks like recommended practice out loud

antonis · Answer