打印视图控制器

Question

我正在构建一个应用程序，它使用一堆文本字段让用户填写医生办公室。然后，他们将点击打印按钮以打印用户填写的pdf页面。我遇到的问题是，我使用的打印代码将其显示为空白文档。

@IBAction func printBtnPressed(_ sender: Any) {

    let pInfo = UIPrintInfo(dictionary:nil)
    pInfo.outputType = UIPrintInfoOutputType.general
    pInfo.jobName = "Print Patient Forms"

    //Set up print controller
    let printController = UIPrintInteractionController.shared
    printController.printInfo = pInfo

    //Assign a UIMage version of my UIView as a printing Item
    printController.printingItem = self.view

    //var pInfo : UIPrintInfo = UIPrintInfo.printInfo()
    pInfo.orientation = UIPrintInfoOrientation.portrait

    let formatter = UIMarkupTextPrintFormatter(markupText: textView.text!)

    printController.showsNumberOfCopies = false

    printController.showsPageRange = true
    printController.printFormatter = pdfView.viewPrintFormatter()
    printController.present(animated: true, completionHandler: nil)
}

有人有任何建议吗？