文本工具包：旧金山的大写数学符号

Question

在介绍新系统字体时，显示以下屏幕截图。哪个UIFontDescriptorFeatureSettingsAttribute用于启用此行为？

Answer 1

如果其他人正在努力解决这个问题，我发现这个功能会激活它：

let descriptor = UIFont.systemFontOfSize(24.0, weight: UIFontWeightLight).fontDescriptor()
let adjusted = descriptor.fontDescriptorByAddingAttributes(
    [
        UIFontDescriptorFeatureSettingsAttribute: [
            [
                UIFontFeatureTypeIdentifierKey: kCaseSensitiveLayoutType,
                UIFontFeatureSelectorIdentifierKey: kCaseSensitiveLayoutOnSelector
            ]
        ]
    ]
)
return UIFont(descriptor: adjusted, size: 24.0)