swift - 初始化CGContext

我正在尝试初始化CGContext（API）

let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]
let url = NSURL.fileURL(withPath: documentsPath + "/datafile")
if let context = CGContext(url: url as CFURL) {
    // stuff
}

但这给了我一个错误：
Cannot invoke initializer for type 'CGContext' with an argument list of type '(url: CFURL)'
我也试过CGContext(url as CFURL)和CGContext.init(url as CFURL)
如果我加上mediaBox: nil我得到：
Ambiguous reference to member 'init(data:width:height:bitsPerComponent:bytesPerRow:space:bitmapInfo:releaseCallback:releaseInfo:)

最佳答案

let url = NSURL.fileURL(withPath: documentsPath + "/datafile") as CFURLRef
let context = CGPDFContextCreateWithURL(url, nil, nil)

关于swift - 初始化CGContext，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/44670658/