fix(ReservationList): prevent FlatList from rendering with empty data #2748
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FlatList has a known bug where it gets stuck and won't render items if it's initially mounted with empty data. This happens because the reservations state starts empty and gets populated in componentDidMount. By the time componentDidMount runs, the FlatList has already been created with data=[], causing it to become unresponsive to new data. This fix shows the loading indicator until reservations are actually populated, avoiding the empty-data initialization issue. Fixes scrolling issues in Agenda where only ~10-20 items would render and users couldn't scroll further. Related: facebook/react-native#39421
tomerdesser
approved these changes
Nov 27, 2025
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Fixes #2750
Problem
The Agenda's ReservationList has a scrolling bug where only the first ~10-20 items render and users can't scroll further. This happens intermittently and is hard to reproduce consistently.
Root Cause
React Native's FlatList has a known issue where it gets "stuck" if initially rendered with empty data (facebook/react-native#39421).
In ReservationList, the state is initialized with
reservations: []in the constructor, and the FlatList renders beforecomponentDidMountpopulates the data. By then, the FlatList is already broken.Solution
Show the loading indicator until
this.state.reservationshas actual data. This ensures the FlatList is never mounted with an empty array.Testing
Tested on a production app with hundreds of agenda items. Before the fix, scrolling would stop after ~20 items. After the fix, all items render and scroll correctly.