we forgot to mention in the release notes but dev0...

# compose

[Andrey Kulikov]

we forgot to mention in the release notes but dev09 also contains new artifact ui-livedata and ui-rxjava2 with adapters for these streams (see commits: livedata, rx). we also hope to provide an adapter for Flow soon

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

Why go through the indirection of returning a State, instead of just returning the value directly? Is it cheaper to “observe” a single model instance’s property multiple times than run this subscription/observation wiring multiple times?

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

I’m guessing the former involves fewer (no?) extra allocations?

[Andrey Kulikov]

Returning raw values causes a frame read to happen as part of returning the value from the subscription function, causing the surrounding scope to recompose for value changes. By returning the underlying State<T> instead we can limit the scope of recompositions while sharing the subscription to different parts of the composition subtree. Plus this state can be used in draw or layout lamdas allowing us to skip recomposition and one redraw when the new value emitted. The syntax is the same as with a regular state { }, and similarly to it property delegation using by makes it easy to simplify the basic usages

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

Cool, thanks for the explanation!