When did my view layout?

on YouTube ↗14m

" summary

Claims that UIKit schedules layout at specific run loop points driven by sources and observers. Demonstrates with a single-button breakpoint and stack trace, uses a simplified run-loop prototype and run loop observers to show when layout runs; finds layout sometimes occurs in source callbacks rather than only observer end-of-cycle, and that forcing layout disables UIKit optimizations. Tools: breakpoints, stack traces, a single-button demo and a fake run loop; results: clarifies timing and gives concrete rules.

AI-written summary · about

" chapters (9)

1. 0:00Layout timing mysteries
2. 1:31UIKit layout computation
3. 3:21Main thread and run loop
4. 6:38Run loop sources and observers
5. 8:47When layout happens
6. 10:13Practical advice
7. 11:18Run loops in iOS apps
8. 12:23Applying knowledge daily
9. 13:07Run loop research challenges

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