使用Swift for iOS以编程方式创建和存储PDF文档

Question

我有一个应用程序,可以查看已存储在项目中的PDF.我希望能够创建一个新的PDF文档并将其存储在app目录中,以便稍后在现有的查看器中查看.PDF将从var todoList: [String] = []显示在a上的数组创建UITableView.我知道要创建一个PDF,我必须创建一个文件名,路径和目录.我不知道该怎么做.我看到了URL和URL请求的在线引用,但我不确定这是否是我想要做的正确途径.有人可以给我一些建议和指导吗？我能找到的一切都是针对Objective-C的.

Answer 1

我用这段代码创建并保存文件(使用HTML)

func createPDF() {
    let html = "<b>Hello <i>World!</i></b> <p>Generate PDF file from HTML in Swift</p>"
    let fmt = UIMarkupTextPrintFormatter(markupText: html)

    // 2. Assign print formatter to UIPrintPageRenderer

    let render = UIPrintPageRenderer()
    render.addPrintFormatter(fmt, startingAtPageAt: 0)

    // 3. Assign paperRect and printableRect

    let page = CGRect(x: 0, y: 0, width: 595.2, height: 841.8) // A4, 72 dpi
    let printable = page.insetBy(dx: 0, dy: 0)

    render.setValue(NSValue(cgRect: page), forKey: "paperRect")
    render.setValue(NSValue(cgRect: printable), forKey: "printableRect")

    // 4. Create PDF context and draw

    let pdfData = NSMutableData()
    UIGraphicsBeginPDFContextToData(pdfData, .zero, nil)

    for i in 1...render.numberOfPages {
        UIGraphicsBeginPDFPage();
        let bounds = UIGraphicsGetPDFContextBounds()
        render.drawPage(at: i - 1, in: bounds)
    }

    UIGraphicsEndPDFContext();

    // 5. Save PDF file

    let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]

    pdfData.write(toFile: "\(documentsPath)/file.pdf", atomically: true)
}

然后我UIWebView用这段代码从文件目录加载它:

func loadPDF(filename: String) {
    let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]
    let url = URL(fileURLWithPath: documentsPath, isDirectory: true).appendingPathComponent(filename).appendingPathExtension("pdf")
    let urlRequest = URLRequest(url: url)
    webView.loadRequest(urlRequest)
}

Answer 2

对于 Swift 3：

createPdf() {
    // 1. Create Print Formatter with input text.

    let formatter = UIMarkupTextPrintFormatter(markupText: textView.text)

    // 2. Add formatter with pageRender

    let render = UIPrintPageRenderer()
    render.addPrintFormatter(formatter, startingAtPageAt: 0)


    // 3. Assign paperRect and printableRect

    let page = CGRect(x: 0, y: 0, width: 595.2, height: 841.8) // A4, 72 dpi
    let printable = page.insetBy(dx: 0, dy: 0)

    render.setValue(NSValue(cgRect: page), forKey: "paperRect")
    render.setValue(NSValue(cgRect: printable), forKey: "printableRect")


    // 4. Create PDF context and draw
    let rect = CGRect.zero

    let pdfData = NSMutableData()
    UIGraphicsBeginPDFContextToData(pdfData, rect, nil)


    for i in 1...render.numberOfPages {

        UIGraphicsBeginPDFPage();
        let bounds = UIGraphicsGetPDFContextBounds()
        render.drawPage(at: i - 1, in: bounds)
    }

    UIGraphicsEndPDFContext();


    // 5. Save PDF file

    let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]

    pdfData.write(toFile: "\(documentsPath)/new.pdf", atomically: true)

    print("saved success")
}