fix(ui): prevent LazyVStack layout hang with 700+ cards#70
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sergioestebance wants to merge 1 commit into
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fix(ui): prevent LazyVStack layout hang with 700+ cards#70sergioestebance wants to merge 1 commit into
sergioestebance wants to merge 1 commit into
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The sidebar ListBoardView used LazyVStack with pinnedViews: [.sectionHeaders], but each section wrapped its cards in an inner LazyVStack. The outer container needed to measure each section to position pinned headers, which required materializing the inner LazyVStack — forcing all ~700 card views to be laid out on every reconciliation cycle. Thread samples confirmed 100% main thread time spent in LazySubviewPlacements.placeSubviews → ForEachList.applyNodes. Two changes: - Remove pinnedViews from the outer LazyVStack so sections are lazily evaluated without full measurement - Replace the inner LazyVStack with VStack so the outer container can size sections via their direct children Also move ChannelShareController drain loops from Task.detached to DispatchQueue.global to avoid blocking the cooperative thread pool with synchronous FileHandle.availableData reads.
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Summary
LazyVStack(pinnedViews: [.sectionHeaders])in the sidebarListBoardView. The outer container needed to measure each section to position pinned headers, which forced materializing all ~700 card views on every reconciliation cycle (3s), permanently blocking the main thread.LazyVStackin section bodies, replacing withVStackso the outer lazy container can size sections via direct children.ChannelShareControllerdrain loops fromTask.detachedtoDispatchQueue.globalto avoid blocking the cooperative thread pool with synchronousFileHandle.availableDatareads.Evidence
Thread samples (
~/.kanban-code/logs/main-thread-samples/) showed 100% of samples inLazySubviewPlacements.placeSubviews→ForEachList.applyNodeswith deeply nested per-item modifier chains. Watchdog log confirmed continuousHANG: main thread blocked for >500msevery 10 seconds for 2+ hours.Test plan
swift test— all 755 tests pass