Compose poll! When you are implementing a complex ...

# compose

[Alex Vanyo]

Compose poll! When you are implementing a complex layout that you can’t build with built-in layout primitives like Row and Column, what approach do you use the most?

1. Modifier.onGloballyPositioned /`Modifier.onPlaced` / Modifier.onSizeChanged
2. Custom Layout
3. Subcomposition (BoxWithConstraints, etc.)

[Ben Trengrove [G]]

Does ConstraintLayout count as a primitive?

[Alex Vanyo]

I think so - I’d also count FlowRow and LazyVerticalGrid as primitives. Complicated primitives, but not “custom”

[Trejkaz]

I don't see anything called ConstraintLayout

[Trejkaz]

doesn't autocomplete, doesn't auto-import if I type it out in full

[Trejkaz]

I really wish the inline docs would be useful

[Trejkaz]

at the moment the most I get is the method signature

[ephemient]

https://developer.android.com/develop/ui/compose/layouts/constraintlayout is in a different artifact

[Trejkaz]

so how do we define a primitive then

[Trejkaz]

if I can pull in another artifact and call that a primitive, I could do damn near anything

[Alex Vanyo]

Agreed, if there’s a perfectly-made layout for your use case in a library then you could just use that. I’m mostly curious about what people reach for when they need something more complex, and they have to build that more complex thing directly

[Trejkaz]

in Swing I was using GroupLayout and I am yet to find anything in Compose nearly as convenient as that

[Trejkaz]

at some point I will probably try to implement that layout in Compose

[Trejkaz]

I just have to get a good idea of what sort of API would look good

[Trejkaz]

and Swing made a number of mistakes like making it very easy for people to hard-code lengths

[eygraber]

I didn't think of #1 and #3 in terms of being general solutions for not being able to use a primitive layout. If anything, I think of them as being special cases of #2.

[Tolriq]

I often choose BoxWithConstraints as it's easier to grasp than customlayouts.

[mohamed rejeb]

Usually I use Modifier.onGloballyPositioned and in some cases where performance matters I use Layout to avoid some recompositions.

[Stylianos Gakis]

For me:
I have had to use onPlaced in scenarios where I want a composable to be scrollable, but for some reason I also want to know the size of it in the scrollable axis, so I have done the chain .fillMaxHeight().onPlaced{save the height here to use somewhere else}.verticalScroll in some places.

Haven't used onGloballyPositioned anywhere yet, onPlaced has always been the thing that suited my needs when I reached for that.
Haven't really used BoxWithConstraints I think.

Layout for everything else.