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iOS - UI API called on a background thread

See original GitHub issue

Description

Random crash / log when reloading the app in dev.

Platforms

iOS
Android
Web

Screenshots

=================================================================
Main Thread Checker: UI API called on a background thread: -[UIView removeGestureRecognizer:]
PID: 52222, TID: 12083840, Thread name: (none), Queue name: com.facebook.react.ShadowQueue, QoS: 33
Backtrace:
4   zinspector3                         0x0000000104d79f78 -[RNGestureHandler unbindFromView] + 124
5   zinspector3                         0x0000000104d84cdc -[RNGestureHandlerRegistry dropAllHandlers] + 280
6   zinspector3                         0x0000000104d7f84c -[RNGestureHandlerManager dropAllGestureHandlers] + 40
7   zinspector3                         0x0000000104d808cc -[RNGestureHandlerModule invalidate] + 52
8   zinspector3                         0x0000000104ef79fc __26-[RCTCxxBridge invalidate]_block_invoke_2 + 72
9   libdispatch.dylib                   0x0000000109db0c6c _dispatch_call_block_and_release + 32
10  libdispatch.dylib                   0x0000000109db27bc _dispatch_client_callout + 20
11  libdispatch.dylib                   0x0000000109dba8a4 _dispatch_lane_serial_drain + 984
12  libdispatch.dylib                   0x0000000109dbb5e0 _dispatch_lane_invoke + 428
13  libdispatch.dylib                   0x0000000109dc8168 _dispatch_workloop_worker_thread + 908
14  libsystem_pthread.dylib             0x000000025120e0bc _pthread_wqthread + 288
15  libsystem_pthread.dylib             0x000000025120de5c start_wqthread + 8
2022-05-10 11:58:11.871015-0300 zinspector3[52222:12083840] [reports] Main Thread Checker: UI API called on a background thread: -[UIView removeGestureRecognizer:]
PID: 52222, TID: 12083840, Thread name: (none), Queue name: com.facebook.react.ShadowQueue, QoS: 33
Backtrace:
4   zinspector3                         0x0000000104d79f78 -[RNGestureHandler unbindFromView] + 124
5   zinspector3                         0x0000000104d84cdc -[RNGestureHandlerRegistry dropAllHandlers] + 280
6   zinspector3                         0x0000000104d7f84c -[RNGestureHandlerManager dropAllGestureHandlers] + 40
7   zinspector3                         0x0000000104d808cc -[RNGestureHandlerModule invalidate] + 52
8   zinspector3                         0x0000000104ef79fc __26-[RCTCxxBridge invalidate]_block_invoke_2 + 72
9   libdispatch.dylib                   0x0000000109db0c6c _dispatch_call_block_and_release + 32
10  libdispatch.dylib                   0x0000000109db27bc _dispatch_client_callout + 20
11  libdispatch.dylib                   0x0000000109dba8a4 _dispatch_lane_serial_drain + 984
12  libdispatch.dylib                   0x0000000109dbb5e0 _dispatch_lane_invoke + 428
13  libdispatch.dylib                   0x0000000109dc8168 _dispatch_workloop_worker_thread + 908
14  libsystem_pthread.dylib             0x000000025120e0bc _pthread_wqthread + 288
15  libsystem_pthread.dylib             0x000000025120de5c start_wqthread + 8

Steps To Reproduce

I could not actually reproduce this after it happened the first time.

Expected behavior

Please, don’t call UI methods on non-UI threads 😄

Actual behavior

UI API called on a background thread

Snack or minimal code example

Package versions

React: 17.0.2
React Native: 0.67.4
React Native Gesture Handler: 2.4.2
React Native Reanimated: 2.8.0

Issue Analytics

State:
Created a year ago
Reactions:2
Comments:5 (2 by maintainers)

Top GitHub Comments

1reaction

MichaelDanielTomcommented, May 11, 2022

Also getting this in our logs, although I’m currently not entirely sure what triggers it.

When this happens, our app usually becomes unresponsive, where both react-native components and native UI elements do not respond to touches, so this unresponsiveness is possibly related.

0reactions

j-piaseckicommented, Jun 23, 2022

Gesture Handler 2.5.0 should fix the issue, if not you can report it again and I’ll reopen the issue.

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Which version? v5.2.42037.1112Latest. To Reproduce(If applicable) Steps to reproduce the behavior: Open iOS demo; Start Share. Screenshots.