Clarify if creation of UIImage on background threads is safe

Originator:futuretap
Number:rdar://27129974 Date Originated:01-Jul-2016 02:47 PM
Status:Duplicate/26954460/Open Resolved:
Product:iOS Product Version:10.0 b1
Classification:Other Bug Reproducible:Always
 
This is a duplicate of rdar://26954460

Peter Steinberger23-Jun-2016 00:28 AM

Area:
UIKit

Summary:
There's been some confusion if *creating* UIImage objects from background thread is safe. The documentation mentions usage, but this does not necessarily mean that objects can be *created* on background threads. And there was a race condition in iOS 9.

Steps to Reproduce:
Read https://github.com/AFNetworking/AFNetworking/issues/2572#issuecomment-227895102

It contains sample code as well (also attached here). This seems to be fixed in iOS 10 (both via testing and my research) BUT the documentation is unclear about it.

Expected Results:
This should be clearly documented.

Actual Results:
Documentation is too vague

Version:
iOS 9.3.2/10b1

Notes:


Configuration:
Xcode 7.3.1/8b1

Attachments:
'UIImageWithDataMultithreaded.zip' was successfully uploaded.

Comments


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