在我的应用中,我想让用户下载和使用字体,但是我不知道如何动态地执行此操作。我知道我们必须在应用程序的Info.plist
文件中指定要使用的字体,但是我们无法以编程方式向该plist文件添加任何内容。有zynga的库,但它是UILabel
的子类。
请帮助
您可以使用CGFontCreateWithDataProvider()
,然后使用CTFontCreateWithGraphicsFont()
。然后,您将获得一个CTFont,可以使用Core Text进行绘制。
据我所知,如果不将字体包含在应用程序包中并使用Info.plist方法(即不下载它)或使用私有API,就无法从自定义字体中获取UIFont。
是,有可能:
/**
Downloads a `.ttf` file from an URL and changes label's font.
- Parameter url: The URL of the `.ttf` file.
- Precondition: The URL Session must be previously configured at ease.
*/
fileprivate func setFont(url: URL) {
// Download the font file in .ttf format.
dataTask = urlSession?.dataTask(with: url,
completionHandler: { [weak self] (data, response, error) in
guard error == nil,
let data = data,
(response as? HTTPURLResponse)?.statusCode == 200,
// Create a Font Descriptor from the raw data.
let ctFontDescriptor = CTFontManagerCreateFontDescriptorFromData(data as CFData) else {
// Error during the download of the .ttf file.
self?.error()
return
}
// Create CTFont from the Font Descriptor and convert it to UIFont.
let font: UIFont = CTFontCreateWithFontDescriptor(ctFontDescriptor, 0.0, nil) as UIFont
// Do whatever you want with the UIFont :)
self?.success(font: font)
})
dataTask?.resume()
}
使用此代码,您可以从Internet下载包含字体的。ttf文件(可以从任何其他来源获取文件)并将其用作UIFont。
是,有可能:
/**
Downloads a `.ttf` file from an URL and changes label's font.
- Parameter url: The URL of the `.ttf` file.
- Precondition: The URL Session must be previously configured at ease.
*/
fileprivate func setFont(url: URL) {
// Download the font file in .ttf format.
dataTask = urlSession?.dataTask(with: url,
completionHandler: { [weak self] (data, response, error) in
guard error == nil,
let data = data,
(response as? HTTPURLResponse)?.statusCode == 200,
// Create a Font Descriptor from the raw data.
let ctFontDescriptor = CTFontManagerCreateFontDescriptorFromData(data as CFData) else {
// Error during the download of the .ttf file.
self?.error()
return
}
// Create CTFont from the Font Descriptor and convert it to UIFont.
let font: UIFont = CTFontCreateWithFontDescriptor(ctFontDescriptor, 0.0, nil) as UIFont
// Do whatever you want with the UIFont :)
self?.success(font: font)
})
dataTask?.resume()
}
使用此代码,您可以从Internet下载包含字体的。ttf文件(可以从任何其他来源获取文件)并将其用作UIFont。