If I try to do `snapshotFlow { mySnapShotStateList}.collectLatest{ //Log.e("UPDATE")}` I won't get...

# compose

[Colton Idle]

If I try to do

snapshotFlow { mySnapShotStateList}.collectLatest{ //Log.e("UPDATE")}

I won't get updates unless I do

snapshotFlow { mySnapShotStateList.toList() }.collectLatest{ //Log.e("UPDATE")}

Yet when I go to use a lazy column or column I don't have to call toList(). Is there any way to know when I'll have to call .toList() to get proper observability as I intended?

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

Something has to actually read the state object. Merely referencing it isn’t reading it

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

Lazy lists need to read the list because they iterate over it, check its size, etc

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

Your case as written is probably gonna be awkward regardless because you’re not actually using any of the data from the list, so there’s no obvious read operation to perform. If you just want to log when the list changes, you can avoid making a copy of the whole list with something like:

snapshotFlow {
  mySnapShotStateList.size
  Log.e("UPDATE")
}.collect()

[Uli Bubenheimer]

@Colton Idle In the case of snapshotFlow the recommended pattern is indeed to use SnapshostStateList.toList(), your use case is why that method was added. It does not make a copy of the list, but uses the immutable/persistent list that it maintains for snapshot state, so no worries.

[Colton Idle]

awesome! thanks everyone. learned something new