is there a way to remember a layout height in comp...

# compose

[dimsuz]

is there a way to remember a layout height in compose? Use-case:

• I have some Box positioned in the screen (it's inside the Column)
• User hits some button, some job begins
• Now I want to hide the box and show a CircularIndicator positioned at that (now invisible) Box's center
In code I do something like if (isJobRunning) Box() else CircularIndicator() but that makes progress bar jump.
In old View system I would wrap them both in FrameLayout and have the indicator use layout_gravity=center while setting box.visibility = INVISIBLE .
What path should I take in Compose?

[Vsevolod Ganin]

You can do the same, wrapping this code with another Box. Box is analogue for FrameLayout

[Vsevolod Ganin]

For layout_gravity=center use Modifier.align for both children

[dimsuz]

But the thing is that only one child can be visible at one moment. And I want that Box to always retain size of the largest child, even if it's not currently in composition. With FrameLayout this is solved by having Invisible state which retains view size during a layout phase. Not so here...

[Vsevolod Ganin]

Ah, now I get it. AFAIK INVISIBLE is Modifier.opacity(0f) now

[dimsuz]

I thought about this, but it felt a bit like a hack, so I thought I'd ask if there's a more idiomatic way 🙂

[Vsevolod Ganin]

Yeah it seems strange for me too. Personally I never had to emulate INVISIBLE. There was a discussion sometime ago and it seems that community agreed on that is INVISIBLE is now opacity(0f) .
https://kotlinlang.slack.com/archives/CJLTWPH7S/p1594659399205900

[Vsevolod Ganin]

There is more interesting solution at the end of the thread, probably you should try it

[dimsuz]

Thank you! 👍