Has anyone implemented a Kotlin solution to creating non-nullable LiveData types? Trying to think of...

# android

[Shan]

Has anyone implemented a Kotlin solution to creating non-nullable LiveData types? Trying to think of the best way to do this.. Right now I have an extension function which will get the value only if it's not null, otherwise throw (as the value should never be null), but I'd much rather do it as a functionality of the setter and force the LiveData to have an initialization value as well as not being able to set it to null.

[Shan]

1. LiveData has a constructor in its class which will initialize the class with no value passed, which I would like to do away with (without making my own observable.. if anyone has any suggestions)

2. LiveData annotates its getValue function with @Nullable which I would also like to do away with.

[louiscad]

My solution is to use Flow and bridge it to LiveData, not exposing MutableLiveData, and I observe only notNull values, with an extension (that I can link if you want)

[Shan]

Please do! That sounds very promising

[Shan]

I intend to replace my LiveDatas with Data Flows when they are released at some point, hopefully soon!

[louiscad]

I think AndroidX LiveData KTX now has these but I'm not sure. Anyway, here are my extensions: https://github.com/LouisCAD/Splitties/blob/de82f24a60bb92198a120634971c41e86dc72c24/modules/arch-lifecycle/src/androidMain/kotlin/splitties/arch/lifecycle/LiveData.kt#L21

The obsolete API annotations are because I plan to remove overlap with KTX artifacts.

To bridge a Flow to a LiveData, here's what you can do with latest LiveData KTX (should be in stable now):

val yourLiveData = liveData {
    myFlow.collect { myData ->
        /*this@liveData.*/emit(myData)
    }
}

[Shan]

LiveData KTX, you mean the third party library? Or is this a part of AndroidX?

[Shan]

Ah, I see it's part of the androidx lifecycle-livedata-ktx library. Very nice! Thanks 👍