Ios 使用CGPDFContextCreateWithURL时PDF中缺少文本

我正在尝试创建一个带有一些标题文本的简单pdf。我正在使用CGPDFContextCreateWithURL创建文档。由于某些原因，没有显示任何文本，但我可以让其他图形对象显示

override func viewDidLoad() {
super.viewDidLoad()

 drawSuperPDF("test4.pdf")
 showPDFFile()

 }

我的drawsupperdf（）函数

My drawHeaders（）和drawHeaderText（）函数

func drawHeaders() {


drawHeaderText(CGPoint(x: 30, y:  10), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 25), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 40), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 70), headerText: "Hello World:", underline: true)




   }

func drawHeaderText(point: CGPoint, headerText: String, underline: Bool) {

let drawingPoint = CGPoint(x: point.x, y: point.y)

if underline {


    var multipleAttributes = [String : NSObject]()
      multipleAttributes[NSFontAttributeName] =     UIFont.boldSystemFontOfSize(12)
    multipleAttributes[NSUnderlineStyleAttributeName] = NSUnderlineStyle.StyleSingle.rawValue


    headerText.drawAtPoint(drawingPoint,
        withAttributes: multipleAttributes)


} else {

    let font = UIFont.systemFontOfSize(12)
    headerText.drawAtPoint(drawingPoint,
        withAttributes: [NSFontAttributeName : font])}

 }

最后，我的showPdfile（）

---

您好：）您没有显示简单的图形调用，但我敢打赌它们将图形上下文作为参数。。。“drawAtPoint”函数不接受图形上下文，因此它可能不知道您要在PDF文件中绘制。看看“UIGraphicsPushContext”；在你的文本调用之前调用它，看看这是否会改善情况：）当我尝试UIGraphicsPushContext时，我只是得到一个没有pdf的屏幕。我还修改了函数以将上下文传递给函数，但没有成功：(

func drawHeaders() {


drawHeaderText(CGPoint(x: 30, y:  10), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 25), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 40), headerText: "Hello World:", underline: true)


drawHeaderText(CGPoint(x: 30, y: 70), headerText: "Hello World:", underline: true)




   }

func drawHeaderText(point: CGPoint, headerText: String, underline: Bool) {

let drawingPoint = CGPoint(x: point.x, y: point.y)

if underline {


    var multipleAttributes = [String : NSObject]()
      multipleAttributes[NSFontAttributeName] =     UIFont.boldSystemFontOfSize(12)
    multipleAttributes[NSUnderlineStyleAttributeName] = NSUnderlineStyle.StyleSingle.rawValue


    headerText.drawAtPoint(drawingPoint,
        withAttributes: multipleAttributes)


} else {

    let font = UIFont.systemFontOfSize(12)
    headerText.drawAtPoint(drawingPoint,
        withAttributes: [NSFontAttributeName : font])}

 }

func showPDFFile() {

let fileName = "test4.pdf"
let documentsURL = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0]
let pdfFileName = documentsURL.URLByAppendingPathComponent(fileName)
let fullPath = pdfFileName.path!
let webView : UIWebView = UIWebView(frame: CGRectMake(0, 0, self.view.frame.width, self.view.frame.height))
let url : NSURL = NSURL(fileURLWithPath: fullPath)
let request : NSURLRequest = NSURLRequest(URL: url)

webView.scalesPageToFit = true
webView.loadRequest(request)

self.view.addSubview(webView)


}