```LazyColumn(modifier = modifier) { for (name...

# compose

[Alexander Suraphel]

LazyColumn(modifier = modifier) {
    for (name in names) {
        Greeting(name = name)
        Divider(color = Color.Black)
    }
}

[Peter Mandeljc]

you're doing it wrong

[Peter Mandeljc]

you shouldn't use for loop

[Alexander Suraphel]

yeah the official doc actually does this:

[Alexander Suraphel]

LazyColumn(modifier = modifier) {
       items(items = names) { name ->
           Greeting(name = name)
           Divider(color = Color.Black)
       }
   }

[Peter Mandeljc]

yeah, they're using "items"

[Alexander Suraphel]

I am not familiar with this paradigmm

[Peter Mandeljc]

no worries

[Alexander Suraphel]

I thought what works for Column must work for LazyColumn

[Alexander Suraphel]

i’m trying to understand what’s different

[Alexander Suraphel]

…

[Alexander Suraphel]

@Peter Mandeljc i think it uses items to recompose on scroll but the error seems misleading i think

[Peter Mandeljc]

items() is a method, that takes a "builder" that builds your item (row) on demand

[Alexander Suraphel]

aha

[Alexander Suraphel]

@Peter Mandeljc

[Alexander Suraphel]

items(items = names) { name ->
           Greeting(name = name)
           Divider(color = Color.Black)
       }

[Alexander Suraphel]

is not working

[Alexander Suraphel]

says items is not a valid parameter

[Alexander Suraphel]

Solved it. Wrong import. Thanks for the help

[CLOVIS]

The difference between Column and LazyColumn is that the second one only computes items that are visible on screen.

If you use for (name in names), you are going through all the names (standard Kotlin syntax), which means you are trying to display all of the names. That's fine for Column, but LazyColumn doesn't want all names, it just wants the ones visible on screen. By using the items function (specific to Compose), you are telling LazyColumn how to compute a single item, and Compose will then use that multiple times on just the items that are on screen.

[Alexander Suraphel]

@CLOVIS that’s how i understood it. I just didn’t feel that the error message is right

[Alexander Suraphel]

it make it look like a syntax error for me

[CLOVIS]

Well, it is an error. It doesn't make sense to force-feed items to a LazyColumn, the LazyColumn decides what is shown, not you.

[Alexander Suraphel]

ok thanks for the explanation @CLOVIS