Unusable or Undebuggable? Rebelling against best practices
summary
Compose LazyColumn drops to 5–10 frames per second in debug on Wear OS devices like the Samsung Galaxy Watch 4, so a drop‑in replacement is implemented that is LazyColumn backed by RecyclerView using a ComposeView per item, a RecyclerView adapter, and submitList diffs to get item animations and preserved input/inertia. Rotary crown and focus issues are solved by forwarding generic motion events to the focused view. The hack runs and makes debug-mode scrolling usable enough to develop before switching to release builds.
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chapters (10)
- 0:00Best practices rebellion
- 1:33LazyColumn animations
- 2:55Performance on Galaxy Watch 4
- 4:43Unusable or undebuggable
- 6:52LazyColumn vs RecyclerView
- 9:38Hacking RecyclerView-backed LazyColumn
- 13:13State-aware LazyColumn scope
- 16:26Rotary input focus issues
- 18:15R8 performance optimization
- 19:41Debugging workflow & final thoughts
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