Do you have a source for that claim? I'm pretty sure that is incorrect. Bytedance has said they use Flutter but for other projects.[0] Douyin is not mentioned anywhere.
I don't have access to any devices with Douyin on it, so I cannot confirm current usage.
My knowledge of their usage is from discussions with ByteDance some many years ago when I was in charge of the Flutter project at Google. At the time they were using Flutter in 50+ applications (probably most of them internal), including Douyin (TikTok for China) as well as physical hardware kiosks on their campus, web apps, etc.
I just tested Douyin 23.5 from 2022[0] and it does not have the two finger scroll bug.[1] It is of course possible they were carrying their own patch for it all this time but that seems unlikely. I doubt they are using Flutter or if they did it must have been a long time ago.
[1] https://github.com/flutter/flutter/issues/11884 - click on the search button in Douyin on the main page and search for something to get to a regular ScrollView. You don't need an account for this.
I wouldn't say its unlikely they carried a patch for it, I just wrote a framework patch that I apply at build time in CI and locally.
I refuse to sideload arbitrary APKs, especially from bytedance. I feel bad because that is irrational, you did, and it'd be really helpful if I did and just did this myself, but, you should install FlutterShark and check: https://play.google.com/store/apps/details?id=com.fluttersha...
Why is "bug" in scare quotes here? It was most definitely a bug.
>I wouldn't say its unlikely they carried a patch for it, I just wrote a framework patch that I apply at build time in CI and locally.
The actual fix was pretty involved. I doubt a large company like Bytedance would want to carry around extra patches at the gesture level that make the dev cycle more difficult. Having one person carry a patch on their local machine is a different story.
Anyway, the Bytedance blogpost says only 200 devs are using Flutter which would make no sense if it was used in Douyin, and LibChecker[0] returns no results for libflutter.so.
> Why is "bug" in scare quotes here? It was most definitely a bug.
Is it? I thought it was cool, I can't think of why its disruptive to scroll a list faster if you scroll with more fingers.
> I doubt a large company like Bytedance would want to carry around extra patches at the gesture level
I'm a solo endeavour, and I spent ~30 minutes to do exactly this (patch gesture behavior) two days ago. I was stunned how easy it is. But I grew up on versioned closed source dependencies on Apple iOS frameworks that you had to patch the runtime at runtime to fix, so I'm easily wowed.
> 200 devs are using Flutter which would make no sense if it was used in Douyin
Seems reductive: "Only" 200 fulltime, 800 in the company...and we're in a discussion about how 50 maintain _the entire framework_. :)
[0] https://flutter.dev/showcase/bytedance