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Could someone explain what is going on here?
I can absolutely not make sense of how the composition works here

Does `currentLines` ever get updated from the `onTextLayout` block? Like if you removed everything else.

Yes, as you can see in the preview -it shows “extraLines=2”

I think you found a bug(limit) with preview + onTextLayout potentially. If I run this code in an app, I get extraLines = 1 and it works as I would've expected it to. If I run it in preview I get what you get

A case like this is a recomposition loop, which you generally want to avoid: <https://developer.android.com/jetpack/compose/phases#recomp-loop>

&gt;  If I run this code in an app, I get extraLines = 1 and it works as I would’ve expected it to.
In an app, you will likely see what is displayed in the preview for a single frame, and then on the following frame, you’ll see what you expect.

The preview is only showing that first frame, where `currentLines` is `0` .

```@Preview
@Composable
fun Repro() {
    var show by remember { mutableStateOf(false) }
    if (show) {
        TextRepeatEmptyLines(text = "Hey", lines = 2)
    }
    LaunchedEffect(Unit) {
        delay(1000)
        show = true
    }
}```
That should make the single frame a bit more obvious if you run it on a device, by delaying it 1 second after launch

I haven't seen this article on the developer docs yet, wow. This actually kind of addresses a lot of problems I've been dealing with.
~Quick question for you Alex! In the article they recommend using a "layout primitive" to solve this cyclic problem of changing state via `onSizeChanged`. I'm not 100% sure what a layout primitive is. Is it just a `Column, Box, Row`?~

Edit: Got it :sweat_smile:

Right, start with built in elements like `Column`, `Box`, `Row` and if you need to do something more custom that isn’t supported with those (or a combination), then go a level deeper and use `Modifier.layout` or `Layout`  (<https://developer.android.com/jetpack/compose/layouts/custom|custom layouts> describes those in detail)

Do you have an idea how this could be done otherwise?
The goal is to have a Text with a minLines

I think <https://issuetracker.google.com/issues/122476634> is the tracking issue for something built-in, but in the meantime `Paragraph` is the utility for measuring the size of text directly.

That’s how `maxLines` is implemented:
<https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:compose/foundation/foundation/src/commonMain/kotlin/androidx/compose/foundation/text/MaxLinesHeightModifier.kt|https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:compose/[…]in/androidx/compose/foundation/text/MaxLinesHeightModifier.kt>

It should be possible to fork a version of that for `minLines` pretty easily?