UIBarButtonItem appearance proxy setting font attributes not working in iOS 11

Question

It seems like the iOS 11 appearance proxy mechanism for setting UIBarButtonItem font is not working completely. (It behaves as expected in iOS 10).

I want to know if this is a bug, or there is somehow a different way to do this.

My code:

NSDictionary *barButtonAppearanceDict = @{NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Light" size:24], NSForegroundColorAttributeName: [UIColor purpleColor]};
[[UIBarButtonItem appearance] setTitleTextAttributes:barButtonAppearanceDict forState:UIControlStateNormal];

Basically, the code appears to work, the button font is styled appropriately. However, when the user taps the button, the style reverts while the button is pressed.

Here's a video:

https://www.dropbox.com/s/hqgpbnlq6gw884p/UIBarButtonItem%20Interaction.mov?dl=0

To repro, create a new app using the Master-Detail app template. Add code snippet above in:

didFinishLaunchingWithOptions

Answer 1

您忘记设置Highlighted样式。

[[UIBarButtonItem appearance] setTitleTextAttributes:barButtonAppearanceDict UIControlStateHighlighted];