Is there a rule of thumb to choose `Column` with `...

# compose

[lesincs]

Is there a rule of thumb to choose Column with Modifier.verticalScroll() or LazyColumn? Seems for every scrollable page we can just use LazyColumn, but the `item {}`makes the development a little bit cumbersome, can I just use Column for the pages which don’t have infinite scrollable content?

[Desmond Teo]

Column will compose and layout every child, while LazyColumn will only layout what is visible (hence lazy), so i’d say it depends on the number of items

[lesincs]

thanks for the clarification, but the tough thing is what's the threshold for the number? how many items when a page reach I should switch from Column to LazyColumn? 🤣

[ste]

AFAIK, you can't nest a LazyColumn inside a scrollable Column yet, so if you need to display a list within a scrollable Column, go for a plain Column

[Colton Idle]

I asked this question like a year ago and the gist of it seemed to be:
1. it can show intent a bit more clearly by using one api over the other
2. in simple cases (stacking two texts on top of each other) there really isn't any benefit of not using a Column
3. There is some overhead to using a Lazy. so if you don't need it, dont use it.
Ill try to find the question though. it had some good input from compose team.

[Colton Idle]

Here it is. Almost 1.5 years ago. Crazy

https://kotlinlang.slack.com/archives/CJLTWPH7S/p1602102472157600

[lesincs]

oh, thank Colton for the reference, I think now I understand more about the API design, maybe for most pages if there isn’t a big performance issue I would just go with Column.😁

[Colton Idle]

Yeah. Personally I've been going for column almost everywhere except when I see that there is lag in release builds. if I see lag, then I convert to a lazy and then the issue goes away. so its almost like a trick i keep in my back pocket at this point for a quick win for perf improvement.

[Colton Idle]

but yes. you could argue that i should just make everything lazy right off the bat. lol

[Chris Sinco [G]]

cc @Ben Trengrove [G]

[Ben Trengrove [G]]

There is no hard and fast rule but the general idea is - with lazy you pay a higher cost per visible item than non-lazy but you will only have items for what can be seen on screen. With Column, you pay a low cost per item but if you have a lot of them thats going to add up pretty fast. Roughly, if you know you will never have that many items then Column/Row is probably all you need. Like most things though you just have to test it out (in release not debug) and see.