UIKit Animation Debugging

About

This skill provides a systematic framework for debugging CAAnimation and UIKit animation logic on Apple platforms. It addresses the high percentage of animation problems rooted in CATransaction timing, layer state, and frame rate assumptions rather than Core Animation bugs. By enforcing mandatory diagnostic steps and providing a clear decision tree, it helps developers identify root causes like duration overrides, retain cycles in completion handlers, and synchronization issues between gestures and layers. It is particularly valuable for ensuring animations perform consistently across various hardware, from legacy devices to ProMotion-enabled displays.

Key Features

• Implementation patterns for synchronizing gesture recognizers with animations using CADisplayLink
• Decision tree for troubleshooting completion handler failures and duration mismatches
• 61 GitHub stars
• Best practices for CATransaction wrapping to prevent unintended property overrides
• Systematic diagnostic workflow for inspecting layer speed, time offsets, and active animation keys
• Device-specific guidance for tuning spring physics across different hardware performance classes

Use Cases

• Resolving cases where animation completion handlers fail to trigger on real hardware
• Eliminating visual stuttering caused by desynchronized gesture and layer updates
• Correcting animation duration mismatches and unexpected layer state reverts