Skip to content

iOS Crash on value change in RNCSliderEventEmitter::onRNCSliderValueChange #782

@hamzadev002

Description

@hamzadev002

This crash is occurring on iOS 26.2 using an iPhone 17 Pro. It is a known issue in the Fabric (New Architecture) C++ layer of React Native when interacting with the RNCSlider component.
Wikipedia
Wikipedia
+2
The crash is triggered by _UIFluidSliderInteraction (part of the Liquid Glass UI redesign in iOS 26) when it attempts to dispatch a value change event to a React component that may no longer be valid in the shadow tree.

Crashed: com.apple.main-thread

0 AppName facebook::react::EventEmitter::dispatchEvent(std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>, std::__1::shared_ptr<facebook::react::EventPayload const>, facebook::react::RawEvent::Category) const + 1370 (shared_ptr.h:1370)

1 AppName facebook::react::EventEmitter::dispatchEvent(std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>, std::__1::function<facebook::jsi::Value (facebook::jsi::Runtime&)> const&, facebook::react::RawEvent::Category) const + 557 (shared_ptr.h:557)

2 AppName facebook::react::RNCSliderEventEmitter::onRNCSliderValueChange(facebook::react::RNCSliderEventEmitter::OnRNCSliderValueChange) const + 403 (function.h:403)

3 AppName -[RNCSliderComponentView RNCSendSliderEvent:withContinuous:isSlidingStart:] + 557 (shared_ptr.h:557)

4 UIKitCore -[UIApplication sendAction:to:from:forEvent:] + 100

5 UIKitCore -[UIControl sendAction:to:forEvent:] + 112

6 UIKitCore -[UIControl _sendActionsForEvents:withEvent:] + 376

7 UIKitCore block_destroy_helper.7 + 3780

8 UIKitCore block_destroy_helper.7 + 6756

9 UIKitCore -[_UIFluidSliderInteraction _handler] + 260

10 UIKitCore -[_UIFluidSliderInteraction _handler] + 72

11 UIKitCore -[_UIFluidSliderInteraction _issueUpdate] + 1368

12 UIKitCore __59-[_UIFluidSliderInteraction initWithConfiguration:handler:]_block_invoke + 32

13 UIKitCore block_copy_helper + 44

14 UIKitCore __swift_memcpy4_1 + 8476

15 UIKitCore block_copy_helper.374 + 40

16 UIKitCore -[_UIAppCACommitFuture _invoke] + 64

17 QuartzCore CA::Transaction::run_commit_handlers(CATransactionPhase) + 120

18 QuartzCore CA::Context::commit_transaction(CA::Transaction*, double, double*) + 9036

19 QuartzCore CA::Transaction::commit() + 644

20 QuartzCore CA::Transaction::flush_as_runloop_observer(bool) + 88

21 UIKitCore _UIApplicationFlushCATransaction + 52

22 UIKitCore __setupUpdateSequence_block_invoke_2 + 352

23 UIKitCore _UIUpdateSequenceRunNext + 128

24 UIKitCore schedulerStepScheduledMainSectionContinue + 60

25 UpdateCycle UC::DriverCore::continueProcessing() + 84

26 CoreFoundation CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 28

27 CoreFoundation __CFRunLoopDoSource0 + 172

28 CoreFoundation __CFRunLoopDoSources0 + 232

29 CoreFoundation __CFRunLoopRun + 820

30 CoreFoundation _CFRunLoopRunSpecificWithOptions + 532

31 GraphicsServices GSEventRunModal + 120

32 UIKitCore -[UIApplication _run] + 792

33 UIKitCore UIApplicationMain + 336

34 AppName main + 8 (main.m:8)

35 ??? 0x185c0ee28 (Missing)

Device: iPhone 17 Pro
iOS Version: 26.2
React Native: 0.77.3
Library: @react-native-community/slider 4.5.5
Architecture: New Architecture (Fabric Enabled)
Thread: com.apple.main-thread

Crash Summary

Crash occurs during slider interaction while dispatching slider value change events through React Native Fabric event emitter.

Relevant stack frames:

facebook::react::EventEmitter::dispatchEvent
facebook::react::RNCSliderEventEmitter::onRNCSliderValueChange
-[RNCSliderComponentView RNCSendSliderEvent:withContinuous:isSlidingStart:]

The crash originates from slider event emission during interaction handled by _UIFluidSliderInteraction in UIKit.

Metadata

Metadata

Assignees

No one assigned

    Labels

    bug reportSomething isn't working

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions