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iosuicollectionviewuiscrollviewuilabel

UILabel missing pixel after scroll and value update

So I have a paginated UICollectionView, and a UILabel on top of it for showing what page the user is currently on.

It starts off at 1, and gets incremented or decremented in the UIScrollViewDelegate didEndDecelerating method based on a simple content offset calculation.

This works just fine, but for some reason, on the simulator for iPhone 12/13 mini, running either iOS 14 or 15, a pixel goes missing after scroll.

Attached image showcases what I mean. It goes missing for all values that are superior to 1, and then back to normal for the first page. I've tried the usual of calling setNeedsLayout/Display and layoutIfNeeded on each value update.

Any ideas?

enter image description here

Solution

  • Turns out it's a known Apple bug with mini simulators. There's tonnes of visual tearing with the iPhone 12/13 mini simulators regardless of iOS version.