@dnfield

Have a couple devices that seem close, going to try to reproduce.

Tried on a Samsung Galaxy Tab S 10.5, did not reproduce.

Tried on Samsung Galaxy Tab 3 Lite, also didn't reproduce.

@iampawan the app I'm trying is just our default app from Flutter create with a text field added. I'm selecting the text field and just typing a bunch of random letters quickly for a minute. I'll try to track down the exact device you're on, but it'd be helpful to know if I'm just not using the right test :)

Also, FWIW, the devices I'm testing are on Android 4.4.2 (API 19) and 4.2.2 (API 17).

They're both armv7/32-bit.

I'm not able to track down a Galaxy Tab J Max either in our device lab, a bigger lab at Google, or on eBay :(

@dnfield no problem. Give me some time. I'll go to the office tomorrow morning IST and I will grab the device and try to perform the same thing with my other apps. Right now, I don’t have the device with me But I actually tried running the same app with the different channel and it started working fine.

@iampawan - it would be super helpful if you could bisect this issue since I'm not able to reproduce it. You should be able to do something like this on beta:

$ git bisect bad
$ git checkout stable
$ git bisect good

You'll then get walked through a bunch of commits by git. Run your app, try typing, if it freezes use git bisect bad, if not git bisect good. Eventually you should find the commit where things went wrong (probably an engine roll). That would help us narrow down things a bit more. If it's an engine roll, it may also be helpful to try all the engine commits in that roll to find out which one was bad.

@dnfield That's a very helpful suggestion. I'll definitely update you as soon as possible.

Note that I'm not marking this as a release blocker since we haven't been able to reproduce yet.

Hi, @tvolkert @dnfield This is what I could get using the above process.

[c382b8e] Roll engine 3dc233f..5540684 (5 commits) (#38756)

Wait ... I didn't complete it. I'll share a new one.

Also, it's not happening with normal text fields but it happens when I have text fields with focus nodes and I unfocus and request focus on other text fields. It's just my assumption though. I can make a video if you need.

Thanks for your help!

So did the bisect identify c382b8e as the commit that introduced this? If you sync to the commit before that commit (2200e58), does the problem go away? That commit is also in v1.9.1, so that would mean the bug is in stable right now...

What would be very helpful is if you could write a minimal sample app whose text field demonstrates this problem, so we can all agree on the code that we're testing against.

@tvolkert Actually I didn't complete it. I am doing it right now but it is taking time because with every commit I need to download the sdk again and again.

Ah, gotcha. Thanks again!

Hi, @tvolkert @dnfield I found the commit. Also, thanks for recommending these commands. I didn't know about it. Also, is there any way of doing this without downloading the SDK and build tools and running the app again and again.

6b66d79 is the first bad commit
commit 6b66d79
Author: Gary Qian garyq@google.com
Date: Wed Nov 20 16:37:10 2019 -0800

Track and use fallback TextAffinity for null affinity platform TextSelections. (#44622)

.../flutter/lib/src/painting/text_painter.dart | 9 +++--
packages/flutter/lib/src/rendering/editable.dart | 35 ++++++++++++++++++--
.../flutter/lib/src/services/text_editing.dart | 4 +--
packages/flutter/lib/src/services/text_input.dart | 5 ++-
.../flutter/test/painting/text_painter_test.dart | 38 ++++++++++++++++++++++
packages/flutter/test/rendering/editable_test.dart | 25 ++++++++++++++
.../flutter/test/services/text_input_test.dart | 31 ++++++++++++++++++
7 files changed, 139 insertions(+), 8 deletions(-)

I hope it helps. Let me know if you want anything else from my side.

@iampawan - just to be clear, if you checkout beta and revert 6b66d79, the issue goes away right?

/cc @gspencergoog or @GaryQian - that commit doesn't strike me as especially fishy, but maybe one of you know something more about Focus nodes and TextAffinity...

@iampawan any luck in getting a minimal app & repro steps in the app that demonstrates the problem?

@tvolkert I was out. Working on that just right now

Thanks!

Hi, @tvolkert @dnfield Pardon me for the worst code 😅I had to write to minimally reproduce it. https://gist.github.com/iampawan/efeff11154c6eba795ddf37730263968

Let me know if it works.

Also, the implementation might be very poorly done by my team mate but it was working for some reason without this weird issue but today because I checked it, may be I would be able to fix it (not sure though) by trying few things in the code. But even if it has any exception or something it should give that error rather than freezing. And it should not work on other commits then. Let me know if you need any other information from my side.

When I try this I can't type anything at all...

@iampawan once you've got a repro that works for you on other devices but not on the device in question, please post the code and we'll give it a look. It sounds like right now it's not working for us on any device.

@kf6gpe can we get this labelled with affected customers to better understand the impact here?

I missed what the code was doing there - I'm still not able to reproduce the keyboard freezing on the 32 bit Samsung tablets I have access to.

cc @timsneath, who should know which of the customers reported this.

cc @GaryQian I took a guess and assigned this to you with a guess at the target milestone, please reassign if you're not the appropriate person. Thanks!

This was indeed introduced by 6b66d79

It is currently rolled back, pending a rewrite to avoid this and a few other flickering bugs this caused.

I will close this as I do not expect to reland without significant reworks.

This may require a hotfix to fix it in stable.

The following reverts are needed to hotfix this: #45698 as well as flutter/engine#14053 engine side

cc @kf6gpe

cc @tvolkert

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.