Question

我正在使用Firebase的iOS数据库，并且设置了常规的数据检索功能，可以在其中将数据打印到控制台，但是我想将数据发布为PDF。问题在于，PDF在Closure之前渲染，因此Firebase中的数据不会发布。我还需要有多个Closure，因为我从数据库中的几个不同位置获取数据。目前，我正在尝试将Firebase的其中一部分仅转换为PDF图纸

override func viewDidLoad() {
    super.viewDidLoad()
    var recipEmail = ""
    let userID = Auth.auth().currentUser!.uid
    var refLegal = DatabaseReference()
    var refBank = DatabaseReference()
    var refOther = DatabaseReference()
    let font = UIFont(name: "Helvetica Bold", size: 8.0)
    let fileName = "pdffilename.pdf"
    var pathForPDF = ""
    var heightSoFar = 25
    let textColor = UIColor.black
    var paragraphStyle:NSMutableParagraphStyle = NSMutableParagraphStyle.default.mutableCopy() as! NSMutableParagraphStyle
    var textFontAttributes = [NSAttributedString.Key : NSObject]()
    let textRect = CGRect(x: 5, y: 3, width: 125, height: 18)
    let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
    let documentsDirectory = paths[0] as! NSString

    pathForPDF = documentsDirectory.appending("/" + fileName)
    UIGraphicsBeginPDFContextToFile(pathForPDF, CGRect(), nil)
    UIGraphicsBeginPDFPageWithInfo(CGRect(x: 0, y: 0, width: 100, height: 400), nil)
    paragraphStyle.alignment = NSTextAlignment.left
    paragraphStyle.lineBreakMode = NSLineBreakMode.byWordWrapping
    textFontAttributes = [
        NSAttributedString.Key.font: font!,
        NSAttributedString.Key.foregroundColor: textColor,
        NSAttributedString.Key.paragraphStyle: paragraphStyle
    ]
    Database.database().reference().child("\(userID)/legalInf").observeSingleEvent(of : .value, with : {(Snap) in
        if let snapDict = Snap.value as? [String:AnyObject]{
            var i = 0
            for each in snapDict{
                var legalO = LegalInfoStorage();
                legalO.name = each.value["name"] as! String
                legalO.id = each.value["id"] as! String
                legalO.phone = each.value["phone"] as! String
                legalO.firm  = each.value["firm"] as! String
                legalO.address  = each.value["address"] as! String
                legalO.email  = each.value["email"] as! String
                legalO.address  = each.value["address"] as! String
                let y = 75*i + 25
                let tR = CGRect(x:5, y:y, width: 200, height: 75)
                let te = legalO.toString() as NSString
                //print(te)
                i += 1
                te.draw(in: tR, withAttributes: self.textFontAttributes)
                print("closure")
            }
        }
    })
    let text:NSString = "Name's Instructions"
    text.draw(in: textRect, withAttributes: textFontAttributes)
    print("drew")
    UIGraphicsEndPDFContext()

    //I have an outlet for the view not shown in this code
    let pView = PDFView(frame: viewForPDF.bounds)
    pView.autoScales = true
    viewForPDF.addSubview(pView)

    // Create a PDFDocument object and set it as PDFView's document to load the document in that view.
    let pdfDocument = PDFDocument(url: URL(fileURLWithPath: pathForPDF))!
    pView.document = pdfDocument
}

我有打印语句，以便可以看到首先运行哪个代码，这就是我得到的输出：

画了
  关闭
  关闭

因此，这意味着PDF在运行检索代码之前已在绘制，因此它仅显示“名称的说明”

从Firebase数据库中的数据制作PDF

0 个答案: