Seb Vidal
7.4K posts

Seb Vidal
@SebJVidal
iOS Developer 👨🏽💻 Chairman of the _UINavigationBarPalette fan club.








CPU and thermal performance in a SwiftUI list explains why we had so many hitches. Even at rest, no scrolling, the CPU screamed at 100% capacity to render every gif, and well past 100% (distributing work across CPU cores) when I scrolled. The “Very High” energy impact rapidly heated my device. The measured thermal trace crept up towards Serious. When I wasn’t paying attention, the app was even killed by the OS, presumably hitting a critical thermal spike. After giving a serious beating to my shiny new A19 chip, the same feed in UIKit produced comparatively nearly trivial CPU and energy usage. * At rest, UIKit dropped as low as 11% CPU utilisation, vs a consistent 100% for the SwiftUI version * Energy usage correspondingly held at High for UIKit, vs Very High for SwiftUI. I gave up waiting for the thermal profile to hit Fair after 3 minutes. Read my scientific performance comparison right here 🧪 blog.jacobstechtavern.com/p/swiftui-vs-u…


Trying to whip up a nice animation for this play control. At some point the UIKit team fixed UIGlassEffect's ability to animate in/out which was broken in 26.0 but it's still not perfect... Notice the transform applied by _UIFlexInteraction resetting without animating. 🥹












@SebJVidal Welcome to SwiftUI. Only Views.




