initialisieren CGContext

Question

Ich versuche 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  
} 

Aber das gibt mir den Fehler zu initialisieren:

Cannot invoke initializer for type 'CGContext' with an argument list of type '(url: CFURL)'

ich auch CGContext(url as CFURL) versucht haben, sowie CGContext.init(url as CFURL)

Wenn ich mediaBox: nil hinzufügen, erhalte ich: Ambiguous reference to member 'init(data:width:height:bitsPerComponent:bytesPerRow:space:bitmapInfo:releaseCallback:releaseInfo:)

Answer 1

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