fix: trigger onViewableItemsChanged when data changes

[intergalacticspacehighway]

Description

FlashList does not re-trigger onViewableItemsChanged callback if the data prop changes. This also varies from React Native's FlatList. The function name onViewableItemsChanged is such that it should trigger if data changes (because it can change the visible items). React Native's VirtualizedList uses a similar approach used in this PR to re-trigger the viewability state in didUpdate.

Fixes (issue #)
#566

Reviewers’ hat-rack 🎩

• Test onViewableItemsChanged fires when data prop changes.

Screenshots or videos (if needed)

Checklist

• I have added a changelog entry following the Keep a Changelog guidelines.

[intergalacticspacehighway]

I have signed the CLA!

[amer-kocan]

We are experiencing the same issue as described in this PR and, when applying these changes by @intergalacticspacehighway, it seems to resolve it for us.

@naqvitalha Are there any plans to merge this and release this properly?

[Fungusjuice]

any update?

[sadenisa]

any updates on this?

[hirbod]

Common guys, please just merge this already! 8th of July!

[hirbod]

@naqvitalha please, merge some of these quality PRs and cut a release. We're playing cat & mouse with patching

[rklf]

any update?

[favazpa]

will this work now?.Any comments?

[hirbod]

@favazpa we gave up with FlashList and are using Legendlist now. It's also up so 20% faster in our tests and has proper support. https://github.com/LegendApp/legend-list

[naqvitalha]

Hi! 👋 Thank you for your contribution to FlashList!

We're now focusing exclusively on FlashList v2 and React Native's New Architecture. As part of this transition, we're closing older pull requests to better focus our review efforts on v2-compatible changes.

If your changes are still relevant:

• Please verify they work with FlashList v2
• Rebase against the latest main branch
• Open a new PR with v2 compatibility in mind
• We'll be happy to review it!

Resources:

• Contributing Guide
• FlashList v2 Documentation

We truly appreciate your effort and contribution. Thank you for helping make FlashList better! 🙏