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Hi all! Has anyone ever used `LifecycleObserver`s for running `suspend` functions or collecting `Flows` via `lifecycleOwner` -&gt; scope?

you might find this <https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:lifecycle/lifecycle-runtime-ktx/src/main/java/androidx/lifecycle/RepeatOnLifecycle.kt;l=63?q=repeatOnLifecycle|https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:lifecycl[…]roidx/lifecycle/RepeatOnLifecycle.kt;l=63?q=repeatOnLifecycle> and this <https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:lifecycle/lifecycle-runtime-ktx/src/main/java/androidx/lifecycle/FlowExt.kt;l=87|https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:lifecycl[…]-runtime-ktx/src/main/java/androidx/lifecycle/FlowExt.kt;l=87> useful

both available in the latest lifecycle-ktx alpha releases

Great! Thanks Adam. I’m assuming then that such a `LifecycleObserver` would only be interested in the `onCreate()` lifecycle method from which to launch coroutines? Otherwise, hooking into `onStart()` etc seems awkward/redundant

On the flipside, `LifecycleObserver` offers nice dependency inversion and direct access to the `LifecycleOwner`, but I can imagine it’d be nice to be able to inject/provide via DI some scoped `Lifecycle` for such “worker” classes that launch coroutines for specific/contained work. Not sure if that’s an anti-pattern, though :thinking_face:

The `lifecycleScope` extension on LifecycleOwner is exactly that, it spans onCreate =&gt; onDestroy: <https://developer.android.com/reference/kotlin/androidx/lifecycle/package-summary#lifecyclescope>

`repeatOnLifecycle` runs one iteration of the given body block each time the lifecycle raises up to at least a given state, i.e. started: <https://developer.android.com/reference/kotlin/androidx/lifecycle/package-summary#repeatonlifecycle>

:thumbsup::skin-tone-3: Even better. So then `LifecycleObserver`s are not really needed any more when doing work via coroutines. Just having a handle to the `Lifecycle` is enough given all these extension functions that are available.

Not directly but all of these are using `LifecycleObserver`s under the hood, they're just nicer to use this way