Why is it when I try to use `MaterialTheme colors ` I get an kotlinlang #coroutines

I get an error of "@Composable invocations can only happen from the context of...", but if I just use a string there instead then it works fine, which shows that my @Composable is actually setup correctly. Code snipipets in thread.

LazyColumn(content = {
    items(
        listOf(
            "test1",
            "test2",
        )
    ) {
        Text(text = it.toString())
    }
})

This works

LazyColumn(content = {
    items(
        listOf(
            MaterialTheme.colors.primary,
            MaterialTheme.colors.onSecondary,
        )
    ) {
        Text(text = it.toString())
    }
})

This does not work.

rnett

02/10/2021, 2:29 AM

I don't have the code in front of me, I'm guessing some part

MaterialTheme

of is

@Composable

(because of the ambient). Note that `LazyColumn`'s

content

isn't composable, but the `items`'s content is.

☝️ 1

Colton Idle

02/10/2021, 2:33 AM

So what's my solution? I can't use MaterialTheme.colors.* as part of my input data?

Adam Powell

02/10/2021, 2:44 AM

/me gazes at the current channel 🤔

☝️ 3

Colton Idle

02/10/2021, 2:44 AM

Whoops!

Adam Powell

02/10/2021, 2:45 AM

Anyway it's because the LazyColumn content lambda isn't itself a composable function

But the body of the items blocks are

Colton Idle

02/10/2021, 2:45 AM

I just want to reference these colors... 😭

Adam Powell

02/10/2021, 2:46 AM

Make the list outside of the actual LazyColumn call and reference the captured val inside

Colton Idle

02/10/2021, 3:09 AM

Hm. I just pulled it out to a top level var in the file

val list = listOf(
    MaterialTheme.colors.primary,
    MaterialTheme.colors.onSecondary,
)

and it has the same error.

Adam Powell

02/10/2021, 3:11 AM

yes, it needs to be in a

@Composable

function.

val list = listOf(
    MaterialTheme.colors.primary,
    MaterialTheme.colors.onSecondary,
)
LazyColumn {
  items(list) {
    // ...
  }
}

Colton Idle

02/10/2021, 3:16 AM

It worked. And I dont wanna lie and say im not defeated. lol I feel so stupid. oh well. Thanks @Adam Powell

😅 2

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