UINavigationBar loses alpha on size class change

Originator:obusek
Number:rdar://36233282 Date Originated:12/28/2017
Status:Open Resolved:
Product:iOS + SDK Product Version:iOS 11
Classification:UI / Usability Reproducible:Always
 
Area:
UIKit

Summary:
When a view controller experiences a size class change (like on iPhone orientation change), UINavigationBars with an alpha value of 0.0 will get reset to 1.0

Steps to Reproduce:
Setup a UIViewController in a UINavigationController, set it's navigationBar's alpha to 0.0, then rotate the device to trigger a size class change. Notice that the navigationBar's alpha becomes 1.0.

Sample app: https://github.com/obuseme/TestNavBar

Expected Results:
The navigationBar's alpha should stay the set value of 0.0

Actual Results:
The navigationBar's alpha becomes 1.0

Version/Build:
Tested on Xcode Version 9.2 (9C40b), iOS 11.2, but present on other iOS versions as well

Configuration:
n/a

Comments


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at bugreport.apple.com before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!