how come I can't use 100.dp.toPx()? I'm following this swipeable to AnchoredDraggable migration gui...

# compose-android

[bryankeltonadams]

how come I can't use 100.dp.toPx()?

I'm following this swipeable to AnchoredDraggable migration guide where they have.

enum class DragValue { Start, Center, End }

@Composable
fun AnchoredDraggableBox() {
    val anchors = DraggableAnchors {
        Start at -100.dp.toPx()
        Center at 0f
        End at 100.dp.toPx()
    }
    val state = remember {
        AnchoredDraggableState(anchors = anchors)
    }
    Box(
        Modifier.offset { IntOffset(x = state.requireOffset(), y = 0) }
    )
}

but toPx() isn't an extension function for me.

[bryankeltonadams]

i found this in the package androidx.compose.ui.unit

* Drawing and Layout are done in pixels. To retrieve the pixel size of a Dp, use [Density.toPx]:

but I don't see any functions declared in this file for toPx

[Mahmoo]

Maybe DraggableAnchor dont give you composable scope

[Pablichjenkov]

https://stackoverflow.com/questions/65921799/how-to-convert-dp-to-pixels-in-android-jetpack-compose

[Pablichjenkov]

It is an extension function declared inside class Density so you need an instance of Density to be able to see this function.

[ascii]

Do something like LocalDensity.current.run { 100.dp.toPx() }

[ephemient]

it is clearer to

with(LocalDensity.current) { 100.dp.toPx() }

than .run {} IMO

[ephemient]

but regardless, contexts where you are dealing with pixel values extend Density, e.g. DrawScope, MeasureScope, PointerInputScope, etc.