Joh*_*pia 11

您必须为UINavigationBar树使用UIBarButtonItem的外观协议:

UIBarButtonItem *barButtonItemProxy = [UIBarButtonItem appearanceWhenContainedIn:
    [UINavigationBar class], [UINavigationController class], nil];

NSDictionary *textAttributes = @{
    UITextAttributeFont : [UIFont boldSystemFontOfSize:12.0f],
    UITextAttributeTextColor : [UIColor whiteColor],
    UITextAttributeTextShadowColor : [UIColor blackColor],
    UITextAttributeTextShadowOffset : [NSValue valueWithUIOffset:UIOffsetMake(0.0f, -1.0f)]
};
[barButtonItemProxy setTitleTextAttributes:textAttributes forState:UIControlStateNormal];
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