Is there a way to tell is a composable running in an initial

Question

Is there a way to tell is a composable running in an initial composition or a recomposition I m building yet another screen transition composable based on `Crossfade` and I want it not animate anything on initial composition

Vsevolod Ganin · Answer

I can only think about a hack with `remember` ``` Composable private fun isInitialComposition Boolean var isInitialComposition by remember mutableStateOf true return isInitialComposition also isInitialComposition = false ``` But maybe there is a conventional way to do this

Sean McQuillan [G] · Answer

< Doris Liu> for animations < Leland Richardson G > for clever composition tricks slightly smiling face

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

I think you can do something like `currentComposer isInserting` true means it s the first composition But for this case that feels like a hack A lot of the animation tools already won t animate when their target is the same as their starting value

Adam Powell · Answer

not sure I d count on that composer API sticking around as public

Doris Liu · Answer

You could initialize a value with something that is not meaningful For example if you build animations based on `CrossFade` you could initialize its internal state to null ```var state CrossfadeState lt T gt by remember mutableStateOf null ``` and update it after your first run logic

Leland Richardson [G] · Answer

`currentComposer inserting` is the most correct and efficient way to do this but I d be curious to see exactly how you re using it

Vsevolod Ganin · Answer

Thanks for all responses I ll try `currentComposer inserting` in a moment and share my code with you guys

Vsevolod Ganin · Answer

Sorry for delay here is what I came up with props to mr < cb> I based my solution on his old gist

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

I m no expert on the transition animation apis but my instinct is that if you have to use `inserting` with it there s probably a better way to write your animation logic or the apis are missing a feature

Adam Powell · Answer

yeah the `inserting` is likely to be acting as a proxy for some other animation state that you probably want to hoist explicitly and construct into a particular initial state to determine this behavior

Adam Powell · Answer

`inserting` seems like the most correct and efficient way to answer what is likely to be the wrong question slightly smiling face

Doris Liu · Answer

I would suggest setting the initState for initializing `TransitionAnimation` using the same logic as how you determine target state <https gist github com vganin 4e846beb8913c70b4886693102ac4b47 file composableswitcher kt L51|here> That way when you call `toState ` in the first composition you ll get an no op as the target state is the same as the initial state

Doris Liu · Answer

Cool implementation BTW +1

Vsevolod Ganin · Answer

Thanks for your ideas with initial state really appreciated I managed to get away from using `inserting` by setting appropriate initial state in `remember` closure If you are interested here is what changed <https gist github com vganin 4e846beb8913c70b4886693102ac4b47 revisions diff 79f7b006e814e81e4584b239fd3c45426def70b13bf091e5a6b1c0911bedd108>