Why is the mutableStateOf not wrapped by remember automatica

Question

Why is the mutableStateOf not wrapped by remember automatically Having to write remember everywhere is just ugly and creates alot of noise

Timo Drick · Answer

You could just create you own function to do that smile

Orhan Tozan · Answer

I know but why isn t there in the first place grin

Timo Drick · Answer

Before it was stateOf and now they removed it to avoid confusion about the function behind this stuff I think it is just to make sure every one needs to think about it smile

Orhan Tozan · Answer

Soon or later everybody will create that function which would be just boilerplate Seems easier if it was included in the library from the start

Orhan Tozan · Answer

Is there ever a case where one wouldn t use remember if he she is using mutableStateOf

Timo Drick · Answer

Yes when you want to use it inside of a normal class not a composable function

Orhan Tozan · Answer

But isn t it the point that State is used inside composable functions only Classes use Livedata flow

romainguy · Answer

You don t have to use live data or flow

Timo Drick · Answer

Livedata is not so kotlin friendly and flow often a little bit over engineered Also livedata is in my opinion more useful for the legacy view system

romainguy · Answer

Your own state classes makes sense too for intrinsic properties of a component

romainguy · Answer

Scroll state or whatnot

Adam Powell · Answer

Once you get past the basic examples the ratio of `remember mutableStateOf ` to `remember MyStateClass ` that uses `by mutableStateOf` internally to create separate observable properties becomes weighted rather heavily towards the latter

Adam Powell · Answer

The presence of the old `state ` helper for this created a hurdle that kept people juggling many state fields themselves long past when they should be grouped within an object because they weren t comfortable with the component primitives involved

Adam Powell · Answer

It also caused people to think you could only create snapshot state objects during composition and we observed people creating duplicate sources of truth and syncing between them to bridge the divide

Adam Powell · Answer

So we decided it was better not to have it to encourage better understanding in the 1 0 timeframe Once these ideas and patterns become well understood in the wider community we might add it back for convenience

Ray Ryan · Answer

Convenience is a four letter word

Ray Ryan · Answer

It s amazing how quickly a convenience becomes an obfuscation

bohregard · Answer

< Adam Powell> can you elaborate a little bit on what you mean by `remember MyStateClass `

Adam Powell · Answer

Objects like ``` Stable class MyStateClass foo Foo bar Bar var foo by mutableStateOf foo var bar by mutableStateOf bar ```

Adam Powell · Answer

that provide semantic grouping of several observable properties into a single concept

bohregard · Answer

I see is the annotation stable required for remember also I assume that any property that changes will result in recomposition

Adam Powell · Answer

` Stable` is not required for remember it s a signal that if you pass the same instance to a composable function that we can skip the child since all of the object s data is observable and will notify the child if it changes

bohregard · Answer

very neat