Getting below error when accessing `layoutCoordinates.positionInRoot()` . This is only happening in ...

# compose

[theapache64]

Getting below error when accessing layoutCoordinates.positionInRoot() . This is only happening in release build.

Fatal Exception: java.lang.IllegalStateException
LayoutCoordinate operations are only valid when isAttached is true

[theapache64]

compose version = 1.1.0-rc01

I can wrap it inside a if(layoutCoordinates.isAttached) but am thinking why this is happening only on release build? 🤔

[Doris Liu]

Do you have a snippet to repro this?

[theapache64]

I haven’t tried this in isolation 🤔 Will try and post the result here 👍

[theapache64]

but any idea why it happened only in release build? 🤔

[theapache64]

I have seen similar issue closed in one of the prev releases -> https://issuetracker.google.com/issues/182551468

[Doris Liu]

Only in release build? That seems odd. Do you have a stack trace?

[theapache64]

androidx.compose.ui.node.LayoutNodeWrapper.localToRoot-MK-Hz9U (LayoutNodeWrapper.kt:767)
androidx.compose.ui.layout.LayoutCoordinatesKt.positionInRoot (LayoutCoordinatesKt.java:103)
com.my.company.TrackModifierKt$track$1$2$1.invokeSuspend (TrackModifier.kt:104) 
kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith (ContinuationImpl.kt:33)
kotlinx.coroutines.DispatchedTask.run (DispatchedTask.kt:106)
androidx.compose.ui.platform.AndroidUiDispatcher.performTrampolineDispatch (AndroidUiDispatcher.android.kt:81)
androidx.compose.ui.platform.AndroidUiDispatcher.access$performTrampolineDispatch (AndroidUiDispatcher.android.kt:41)
androidx.compose.ui.platform.AndroidUiDispatcher$dispatchCallback$1.run (AndroidUiDispatcher.android.kt:57)
android.os.Handler.handleCallback (Handler.java:938)
android.os.Handler.dispatchMessage (Handler.java:99)
android.os.Looper.loop (Looper.java:246)
android.app.ActivityThread.main (ActivityThread.java:8633)
java.lang.reflect.Method.invoke (Method.java)
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:602)
com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1130)

[theapache64]

So TrackModifier.kt:104 has a positionInRoot() call inside a onGloballyPositioned modifier

[Doris Liu]

Are you doing the query in the onGloballyPositioned callback, or did you cache the layoutCoordinates and used it at a different time?

[theapache64]

Ahh.. now am getting it. There’s coroutine involved here. The layoutCoordinates are used just after the launch. During the scroll the slight delay might be causing the issue. but am wondering why it wasn’t happening before 🤔

[theapache64]

Anyways, that should be the reason.

[Doris Liu]

Yea, the positionInRoot only guarantees correctness if you query it after the layout pass is done.

[theapache64]

what if i use the isAttached flag before accessing positionInRoot ? would that help me with the crash. ?

[Doris Liu]

That'll probably work. By the time the node you are querying is attached, all its ancestors would've been attached also.

[theapache64]

Cool 👍 Will give it a try.