When updateing to Android Studio 4.2 canary 8 and ...

# compose

[Timo Drick]

When updateing to Android Studio 4.2 canary 8 and gradle build tools 4.2.0-alpha8 i get following compiler error:
LiveLiterals$ComposeWidgetsKt.class: D8: com.android.tools.r8.errors.b: Space characters in SimpleName 'Int$arg-0$call-layout$branch$if$fun-measure$class-$no name provided$$arg-0$call-then$fun-visibility' are not allowed prior to DEX version 040
Compiling with classpath 'com.android.tools.build:gradle:4.2.0-alpha07' works fine. also upgraded to gradle 6.6-rc-6

[romainguy]

That bug was reported on another Slack channel, @Leland Richardson [G] can give more info

[Leland Richardson [G]]

eh. this bug is freaking me out a bit.

So the root cause of the bug is from the compose compiler treating an anonymous class incorrectly because its name has a space in it. It’s a simple bug and should be fixed soon.

BUT, the bigger issue is that this is a bug from code that shouldn’t get run except for in the Preview tool in studio.

Can you clarify:
1. this bug is happening in a normal gradle build from command line?
2. if yes, does it persist when you blow away your gradle cache?

[Timo Drick]

1. yes it happens also on command line
2. it perists when i am deleting the .gradle project folder and also deleting the ~/.gradle/caches folder
It only fails in my little bit more complex projects not in a simple hello world sample

[Leland Richardson [G]]

well the error message can show you the root cause and you can get around the exception (looks like there is a top level visibility function which calls then which passes in an anonymous class as the first argument. If you change this to a named-class the error will go away

[Leland Richardson [G]]

but if you can not do that first and help me diagnose why this code is running in the first place, i would be very grateful 🙂

[Leland Richardson [G]]

can you try adding this to your gradle file?

[Leland Richardson [G]]

kotlinOptions.freeCompilerArgs += ['-P', 'plugin:androidx.compose.plugins.idea:liveLiterals=true']

[Leland Richardson [G]]

or actually, “false” is what we want here

[Leland Richardson [G]]

kotlinOptions.freeCompilerArgs += ['-P', 'plugin:androidx.compose.plugins.idea:liveLiterals=false']

[Leland Richardson [G]]

i wonder if that fixes it

[Timo Drick]

added it but does not helped

[Leland Richardson [G]]

with false or true?

[Timo Drick]

Both

[Leland Richardson [G]]

hmm. i’m not sure the flag is correct then

[Leland Richardson [G]]

maybe

kotlinOptions.freeCompilerArgs += ['-Pplugin:androidx.compose.plugins.idea:liveLiterals=false']

[Leland Richardson [G]]

if that doesn’t work, i’ll stop trying to get you to try stuff and just work on reproducing myself, sorry

[Leland Richardson [G]]

you should be able to fix it by changing the anonymous class to a named one

[Timo Drick]

But i was able to solve the problem by following your description

[Leland Richardson [G]]

(there is nothing wrong with your code, it is a bug in the compose compiler)

[Timo Drick]

tried the Ppluginandroidx.compose.plugins.idealiveLiterals=false' but did not solved the problem

[Leland Richardson [G]]

but the code that is causing it shouldn’t be running in the first place

[Timo Drick]

I do not have any compose previews in my code. And also removed the androidx.ui:ui-tooling dependency but the problem is still there

[Leland Richardson [G]]

yeah its a different code generation pathway

[Leland Richardson [G]]

but not supposed to be on by default

[Leland Richardson [G]]

i fear this may be a bug with AGP

[Timo Drick]

@Leland Richardson [G] thank you for your fast response. So at least i am able to use canary 8 now 😄

[Leland Richardson [G]]

no problem

[Leland Richardson [G]]

fair warning though: if this codegen is running, the resulting compose code will not be as efficient as it should be. so please don’t go posting any “compose is slow” blog posts in the mean time if you don’t mind 😱

[Timo Drick]

oh i just saw that i tested the compiler options on the wrong module. Please let me rerun the tests. Just a second

[Leland Richardson [G]]

that would be great, thanks!

[Timo Drick]

No sorry set the options on every module.
The problem code is inside of a library module. And the library itself compiles fine. Just when i use the library in an app module the app module will not compile

[Leland Richardson [G]]

yeah the bug itself is happening in the dex phase, so you will only see it when you build the app

[Leland Richardson [G]]

but that flag (though the format of these flags always elude me so i might just be off by a character somewhere) was supposed to turn this off. but AGP could be re-setting it in a way that it’s not able to be turned off 😕

[Timo Drick]

Btw. i am working now for several month with compose and i was able to measure an increase in performance in my custom LazyColumn implementations. Now the release builds are near to the performance of legacy android recyclerview lists.
(I do tests with many images also loading images in background during fast scrolling throw the list)
Showing the HWUI rendering Bars now constantly under the green line (most of the time just half the way to green)

[Leland Richardson [G]]

ah cool. good to hear. are your lazycolumn implementations OSS?

[Timo Drick]

What do you mean with OSS?
I just started a custom one before AdapterList worked well. I think now the official LazyColumn implementation is stable but still misses some features.
My implementation works a little bit different than the official one. It just uses Layout and dynamically changing the child views that are rendered. But performance wise it is very close to the LazyColumn implementation.
https://gitlab.com/timod/compose-playground/-/blob/master/compose_list/src/main/java/de/drick/compose/list/LayoutList.kt

[Timo Drick]

scroll_performance_test_dev17.mp4

[Leland Richardson [G]]

This is excellent! Thanks for sharing. Indeed LazyColumn is missing a lot of features / use cases still while we nail down the API. It makes me really happy to see folks like you diving in and making your own though! Very cool.

Do you mind if I point people to this from time to time? BTW, by “OSS” i mean “is it open source” which could mean a few things i guess, but I was mostly curious if you were planning on publishing it as a 3rd party library alternative to LazyColumn (which I think would be great, just to be clear).

[Timo Drick]

Of course i would be happy if you point out my implementation. But it is also under heavy development and also misses features 🙂 (Just solved some things i need)
Currently i am playing around getting flows working as input. For this i need a feedback when the end of list is reached.

[Timo Drick]

I am planning to release this also as a library.