fix(now-indicator): use UI-thread visibleDateUnixAnim to eliminate debounce delay#33
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…bounce delay Replaces useDateChangedListener (JS thread, ~200 ms double-debounce via useSyncedList + VisibleDateProvider) with visibleDateUnixAnim from useCalendar. dayIndex and inRange are now derived values on the UI thread, so opacity updates per scroll frame without a React re-render. This mirrors the approach used by useVisibleDayUnix for week-header chips.
This was referenced Jun 9, 2026
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Problem
When swiping between weeks, the now-line show/hide was delayed by ~200 ms due to a double-debounce in the JS thread path:
useSyncedList— 150 ms debounceVisibleDateProvider— 50 ms debounceuseDateChangedListenerreads from this debounced JS-thread value, so the now-indicator's visibility update always lagged behind the scroll.Solution
Replace
useDateChangedListenerwithvisibleDateUnixAnimfromuseCalendar. This shared value is updated immediately on the UI thread whenever a column boundary is crossed — the same source already used byuseVisibleDayUnixfor week-header day chips.dayIndexandinRangeare converted touseDerivedValueworklets so opacity is driven directly on the UI thread per scroll frame, with no React re-render needed for show/hide.The
inRangeflag is threaded intoNowIndicatorInneras an optionalSharedValue<boolean>prop so the inner component stays reusable (e.g.NowIndicatorResourcecontinues using its own logic unchanged).Changes
NowIndicator.tsx: replaceuseMemo+useDateChangedListenerwithuseDerivedValueworklets readingvisibleDateUnixAnim; add optionalinRange: SharedValue<boolean>prop toNowIndicatorInner; remove JS-thread early-return guard (replaced by UI-thread opacity)