Modifications to the > layout engine must not be performed from a background thread after it has been accessed from the main thread

Question

I just downloaded iOS 13 for my iPhone and the new Xcode. I wanted to test my app for iOS 13, but when I try to run my app it will give me a error after a few seconds. Error

Answer 1

For anyone having problems pinning down the cause, try the following.

Click on your scheme (next to the stop button), then Edit Scheme.

Under Run -> Diagnostics you have to activate Main Thread Checker.

As indicated by the breakpoint that got added, your execution will now halt when you try to alter the UI on a non-main thread.