Sebas

Resaca V4 moves to Compose Multiplatform! 🎉 This library lets you to scope ViewModels to a Composable, surviving configuration changes and navigation, now available in Android and iOS + you can use a separate ViewModel for each item in a Lazy list 🤯 github.com/sebaslogen/res…

@camaelon @johnhoford I ❤️ this, even if couldn't see the presentation, the technology is really awesome! I can't wait to start using it in SDUI apps 😍 Also thanks for putting the slides online for us! speakerdeck.com/camaelon/intro…

Come see @johnhoford and I next week in London -- we have some cool stuff to show off :-)

@droidconLondon @johnhoford @camaelon I would love to see this one but I can't find it in the Londond 2025 playlist, are you guys planning on sharing this gem soon? youtube.com/watch?v=l9mS5X…

Ready for a double dose of brilliance? Join @johnhoford & @camaelon 👏 In this #dcldn25 session, discover #RemoteCompose: an #AndroidX framework to project rich, animated #UI from apps or servers onto remote surfaces. london.droidcon.com/speakers

Call for Speakers for @kotlinconf 2026 is open only for a few more hours and I've just submitted a session about using Native Swift gRPC with the new SPM support in KMP! 🤞🤞 sessionize.com/kotlinconf-202…

@kihaki @joe_ptrkv_ch @JorgeCastilloPr Activity and Fragment lifecycles are wonderful 😅

@kihaki @joe_ptrkv_ch @JorgeCastilloPr No isFinishing helps detect beginning of Activity recreation, tricky part is to detect when new Activity finished creation, resume & composition with same/different Composables than when it started recreation There are 50+ tests for edge cases in resaca: #L115" target="_blank" rel="nofollow noopener">github.com/sebaslogen/res…

Composable-level scoped ViewModels are possible with Resaca 👇

@kihaki @joe_ptrkv_ch @JorgeCastilloPr Unfortunately, detecting when an Activity is restarted and the Composable is not part of the Composition is quite tricky Hardcoding a delay will sometimes fail, waiting for the first frame solves this (not trivial) Feel free to check the docs for more info #rememberscoped-lifecycle-internal-implementation-details" target="_blank" rel="nofollow noopener">github.com/sebaslogen/res…

@sebaslogen @joe_ptrkv_ch @JorgeCastilloPr Wasn’t too hard to figure out tbh. It’s a bit of a pitty with the activity dependency for multiplatform but not too hard to solve either:

@raamcosta @JetpkComposeApp Safe approach 👍 If you're interested in understanding the details, this documentation section of the Readme is the best place to start before digging at the API docs #rememberscoped-lifecycle-internal-implementation-details" target="_blank" rel="nofollow noopener">github.com/sebaslogen/res…

@sebaslogen @JetpkComposeApp If I don’t understand it I don’t know whether it will be retained or not, feels weird. I don’t like using things I don’t understand ahah 😅

ViewModel scoping in Compose has been broken from day one. You can only scope to Activity or navigation graphs, but Compose wants fine-grained components. Enter Resaca - the library that fixes this beautiful mess 🧵

@kihaki @joe_ptrkv_ch @JorgeCastilloPr That's a good starting point and how this library started. Unfortunately the third point is way more complicated than it looks like and it only works on happy flows😰It took years to figure out all the edge cases with Android lifecycle. The other platforms are dead simple.

Very simple version would be this: - activity scoped viewmodel holding a viewmodelstore for your composable scoped VMs (you can also keep it as non config instance but an activity scoped VM is a bit more flexible) - custom version of remember that puts your composable scoped vms into that store with the composable position hash as key - make sure to do something like disposableEffect for clearing this composable scoped VM when it makes sense in your architecture (might just be a few seconds after the composable left the comp.) Roughly like that, didn’t take us longer than a day to get a prototype running, worked really well. If you DM me I can send you the working code, so it’s easier.

@raamcosta @JetpkComposeApp It's complicated so it doesn't fit in a tweet but the gist is:if the screen is not "really destroyed" but the Composable is disposed of, then resaca keeps it safe until the screen is active again to reuse it, only if requested again from the same spot.

@sebaslogen @JetpkComposeApp How does it distinguish between leaving composition for good and leaving briefly or due to being in the back stack? Is it just a timing thing?

@dev_atrii @JetpkComposeApp Yes, there is even a resaca-koin version for some extra integration with Koin

@JetpkComposeApp works fine with koin?

Your future self will thank you for attending @sebaslogen's talk 🚨 #JetpackCompose is fast—until it's not. Learn how #Kotlin quirks impact performance & how one commit can fix it. Boost #Compose efficiency with smart tricks at #AMxDC25 androidmakers.droidcon.com/sebastian-loba…

Stop using this app. Musk is messing with your feed. Try the butterfly app!

Check this newsletter by @vinaygaba jetpackcompose.app/newsletter #AndroidDev #JetpackCompose

Very excited and proud to see my last @droidconBerlin talk online🎉 Dependency injection: Koin vs Kotlin-inject 💉 in #KMP TBH, it's way better than the cocktail of nerves I remember😅plus I had a lot of fun😃 Check it out! droidcon.com/2024/08/30/koi…

@Weekly_Android It depends, it always depends😅 The size of an almost empty ViewModel is <0.2kB so it's ok for a bunch of VMs but I'll be mindful of too many. That you can use 1M VMs for a screen doesn't mean that you should. IMHO, good architecture has more impact than optimizing before needed

@sebaslogen How performant is using a separate viewmodel for EACH item?

Resaca V4 moves to Compose Multiplatform! 🎉 This library lets you to scope ViewModels to a Composable, surviving configuration changes and navigation, now available in Android and iOS + you can use a separate ViewModel for each item in a Lazy list 🤯 github.com/sebaslogen/res…

@belin_wu The gist: use rememberKeysInScope + list of keys for the VMs you wanna keep. Put it outside of both lazy lists & you get a KeyInScopeResolver. Then in lazy lists use viewModelScoped with the keyInScopeResolver and the key of that VM 🪄 to get VMs Docs: #scoping-in-a-lazycolumn-lazyrow-etc" target="_blank" rel="nofollow noopener">github.com/sebaslogen/res…

@sebaslogen Great library, I got question for you, how to use a separate ViewModel for each item of a lazy list nested in another lazy list?

We're excited to build the best droidcon Italy agenda EVER. 🎉 🎙️Submit your talk. Share with your network. Let's make sure this opportunity reaches deep within the #Androiddev community 🌐 Go see on the site... #dcnit #droidconit #androidcommunity #androiddevs