https://kotlinlang.org logo
Channels
Powered by
s

Stylianos Gakis

08/25/2023, 8:00 AM
Was playing with the idea of wrapping some screen’s content in an AnimatedContent block to make the transitions between content-error-loading states a bit nicer and I got a code block that looks something like this
Copy code
AnimatedContent(uiState) { uiState ->
  when(uiState) {
    us Error -> { ErrorComposable() } 
    is Loading -> { Spinner() } 
    is Content -> { ScreenContent(uiState) } 
  }
}
Now thing is, when my uiState goes from being Content with some parameters, to still being content, but with some changed state, (like from 
Content(someState = true)
to 
Content(someState = false)
) my AnimatedContent animation still plays, which is of course not what I am looking for here. Is there some approach I am missing here as to how to not make AnimatedContent consider these two Content cases things that it needs to animate between?
Oh hmm, might’ve rubber ducked myself again, since looking inside AnimatedContent, it doesn’t take a 
key
for the content by itself, but just 1 layer deeper, when using 
updateTransition
, the 
transition.AnimatedContent
function does seem to take a 
contentKey: (targetState: S) -> Any? = { it },
parameter, which should allow me to pass the same key for the cases that the AnimatedContent should consider as the same state
f

Filip Wiesner

08/25/2023, 8:03 AM
Yes, the 
contentKey
is definetly what you are looking for 👍 I had the same problem recently
🎯 1
s

Stylianos Gakis

08/25/2023, 8:04 AM
Thanks for confirming! Trying it out atm 👀
f

Filip Wiesner

08/25/2023, 8:04 AM
But I think I remember seeing the 
contentKey
in regular animated content somewhere 🤔 Maybe some beta version of Compose
s

Stylianos Gakis

08/25/2023, 8:05 AM
yeah could be, because I don’t see it ATM. Not on the latest BOM either though unfortunately, so it may be me who’s a bit behind on versions here
Yes! Did this
Copy code
contentKey = { uiState ->
  when (uiState) {
    is HomeUiState.Error -> "Error"
    HomeUiState.Loading -> "Loading"
    is HomeUiState.Success -> "Success"
  }
},
And it works exactly as I wanted it to, super nice! Maybe I could make this a bit simpler, like uiState::class in the lambda, but idk if I wanna rely on something like that after r8 runs etc. What did you do when you had to use it?
f

Filip Wiesner

08/25/2023, 8:06 AM
Yeah, it's fine as it is now. This is my setup
🤯 1
s

Stylianos Gakis

08/25/2023, 8:38 AM
Right, should still pose no problem even after minification as they still will be distinct classes so I should worry about that I suppose. It’s just that I read this thread the other day https://twitter.com/theapache64/status/1693527840401379491 and now I am unreasonably scared for these things 😅
f

Filip Wiesner

08/25/2023, 9:04 AM
Yeah, I had this on production for maybe a month and no problems so far
thank you color 1
a

Alex Vanyo

08/25/2023, 5:42 PM
For reference, 
1.5.0-alpha04
is the version that introduced the 
contentKey
argument on the main 
AnimatedContent
call (without having to go a level deeper to 
transition.AnimatedContent
) https://developer.android.com/jetpack/androidx/releases/compose-animation#1.5.0-alpha04
gratitude thank you 1
s

Stylianos Gakis

08/25/2023, 6:01 PM
Nice, thank you Alex! Been slacking on updating things and am on a bit of an older version of compose ever since I've encountered this https://issuetracker.google.com/issues/291524052 basically. Now I'm reluctant to upgrade because I don't want to go through the work of copying again an entire material3 dependency just to make one internal thing not be internal anymore 🫣🫣 I'm hoping to skip upgrading until and if this is ever addressed, or until I finally take the L and put in the effort to do what I just said.
58 Views
Powered by