Drag and Drop in Compose!

on YouTube ↗15m

" summary

Two years of work distill into a practical migration: built a lazy-column rearrange for Compose that shipped on millions of Trello users, first with a pointer input method (pointerInput + graphicsLayer + visibleItemsInfo) that handled long-press drag, rearrange-by-midpoint and visual tweaks but clipped when dragging outside parent and broke for offscreen tall items. Reworked to use Compose 1.6 drag and drop source / target APIs with a simplified drag drop state, fixed ghost duplication and global coords, now working but limited by targets needing composition at drag start and tight ghost-canvas sizing.

AI-written summary · about

" chapters (9)

1. 0:00Drag and drop in Compose
2. 1:04What drag and drop is
3. 2:05Why Compose for drag and drop
4. 3:32Pointer input method
5. 6:59Pointer input merits and pitfalls
6. 8:44Compose 1.6 APIs approach
7. 11:33New APIs improvements
8. 12:15Forward-thinking improvements
9. 14:00Closing and resources

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