Native crash on mount when using dataBind with ViewModel state machine value-change actions in .riv files #428

Bug: Native crash on mount when using dataBind with ViewModel state machine value-change actions

Description

Binding a ViewModel instance to RiveView via dataBind causes a native crash on mount whenever the loaded .riv file contains state machine ViewModel value-change actions.

The crash happens during file initialization regardless of whether those actions are reachable from the initial state, and cannot be caught by a React error boundary.

Provide a repro

Minimal code reproduction

function RivePreview() {
  const { riveFile } =
    useRiveFile(require('./vm_value_change_test.riv'));
  const [instance, setInstance] = useState(null);

  useEffect(() => {
    if (!riveFile) return;
    let cancelled = false;

    (async () => {
      const vm = await riveFile.viewModelByNameAsync("TextModel");
      const inst = await vm?.createDefaultInstanceAsync();
      if (!cancelled) setInstance(inst ?? null);
    })();

    return () => {
      cancelled = true;
    };
  }, [riveFile]);

  if (!riveFile || !instance) return null;

  // Crashes on mount if .riv contains state machine ViewModel value-change actions
  return <RiveView file={riveFile} dataBind={instance} />;
}

Steps to reproduce

1. Load a .riv file whose state machine contains ViewModel value-change actions.
2. Create a ViewModel instance via the async API and pass it via dataBind.
3. Native crash occurs during mount. No JS exception is thrown.

Expected behavior

When a ViewModel instance is bound via dataBind, state machine ViewModel value-change actions should apply to the bound instance without causing a native crash.

Actual behavior

• App crashes natively during mount
• No JavaScript error is thrown
• React ErrorBoundary does not catch the crash

Things confirmed NOT to prevent the crash

• autoPlay={false}
• Moving the action to a state disconnected from the initial state
• Using async API (viewModelByNameAsync / createDefaultInstanceAsync) instead of useViewModelInstance
• Wrapping in a React ErrorBoundary
• Not calling any JS-side setters

Removing the ViewModel value-change actions from the state machine in the Rive editor eliminates the crash entirely.

Source .riv / .rev files

A ZIP containing both the runtime .riv and the editor .rev file will be attached.
vm_value_change_test.zip

Device & versions

• Device: iPhone 13 Pro Max (physical device)
• OS: iOS 26.3.1
• React Native: 0.83.6
• Expo: 55.0.17
• @rive-app/react-native: 0.4.6

Additional context

The JavaScript side completes successfully: the .riv file loads, the ViewModel instance is created, and RiveView mounts before the native crash occurs.