iOS 11 (15A5362a): UINavigationItem.prompt colour/font are fixed and ignore attribute values specified in UINavigationBar.titleTextAttributes

Originator:ttlisshort
Number:rdar://34009213 Date Originated:8/22/2017
Status:Open Resolved:
Product:iOS Product Version:iOS 11 (15A5362a)
Classification:Regression Bug Reproducible:Always
 
Area:
UIKit

Summary:
iOS 11 (15A5362a):

UINavigationItem.prompt colour/font are fixed and ignore attribute values specified in UINavigationBar.titleTextAttributes (unlike iOS 9.x and iOS 10.x)

Steps to Reproduce:
1. Create new single-view App
2. Open storyboard and embed ViewController in NavigationController
3. Add the following to ViewController.viewDidLoad():

navigationController?.navigationBar.titleTextAttributes =
            [NSAttributedStringKey.foregroundColor: UIColor.red,
             NSAttributedStringKey.font: UIFont.systemFont(ofSize: 20)
        ]
        
        navigationItem.title = "My Title"
        navigationItem.prompt = "My Prompt"

4. Run the project on iOS 11.0 simulator or on device running iOS 11 b7 (15A5362a).

Expected Results:
As is it currently works in iOS 9.x and 10.x, the expectation is that:
1- The text color is the same as the color specified by NSAttributedStringKey.foregroundColor.
2- The text font is the same as the font specified by NSAttributedStringKey.font
3- The text font size is around 25% smaller than the font size specified in NSAttributedStringKey.font.

Running the project on iOS 10.3 or iOS 9.3, the prompt text is in red and the font is SFUIDisplay, 15.0pt 

Observed Results:
Prompt text colour is black
Font is .SFUIText 13.00pt


Version:
iOS 11 (15A5362a)
Xcode Version 9.0 beta 6 (9M214v)

Comments


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