PDFKit框架详细解析 （三） —— 基于PDFKit的PDF文档的创建和分享（二）

版本记录

版本号	时间
V1.0	2019.09.16 星期一

前言

今天翻阅苹果的API文档，发现多了一个框架就PDFKit，看了下才看见是iOS11.0新添加的框架，这里我们就一起来看一下框架PDFKit。感兴趣的可以看下面几篇文章。
1. PDFKit框架详细解析 （一） —— 基本概览（一）
2. PDFKit框架详细解析 （二） —— 基于PDFKit的PDF文档的创建和分享（一）

源码

1. Swift

首先看下工程组织结构

下面就看一下sb中的内容

下面就是代码了

1. PDFPreviewViewController.swift

import UIKit
import PDFKit

class PDFPreviewViewController: UIViewController {
  public var documentData: Data?
  @IBOutlet weak var pdfView: PDFView!
    
  override func viewDidLoad() {
    super.viewDidLoad()
    
    if let data = documentData {
      pdfView.document = PDFDocument(data: data)
      pdfView.autoScales = true
    }
  }
}

2. FlyerBuilderViewController.swift

import UIKit

class FlyerBuilderViewController: UIViewController {
  @IBOutlet weak var scrollView: UIScrollView!
  @IBOutlet weak var flyerTextEntry: UITextField!
  @IBOutlet weak var bodyTextView: UITextView!
  @IBOutlet weak var contactTextView: UITextView!
  @IBOutlet weak var imagePreview: UIImageView!
  
  override func viewDidLoad() {
    super.viewDidLoad()
    
    // Add subtle outline around text views
    bodyTextView.layer.borderColor = UIColor.gray.cgColor
    bodyTextView.layer.borderWidth = 1.0
    bodyTextView.layer.cornerRadius = 4.0
    contactTextView.layer.borderColor = UIColor.gray.cgColor
    contactTextView.layer.borderWidth = 1.0
    contactTextView.layer.cornerRadius = 4.0
    
    // Add the share icon and action
    let shareButton = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(shareAction))
    self.toolbarItems?.append(shareButton)
    
    // Add responder for keyboards to dismiss when tap or drag outside of text fields
    scrollView.addGestureRecognizer(UITapGestureRecognizer(target: scrollView, action: #selector(UIView.endEditing(_:))))
    scrollView.keyboardDismissMode = .onDrag
  }
  
  @objc func shareAction() {
    // 1
    guard
      let title = flyerTextEntry.text,
      let body = bodyTextView.text,
      let image = imagePreview.image,
      let contact = contactTextView.text
      else {
        // 2
        let alert = UIAlertController(title: "All Information Not Provided", message: "You must supply all information to create a flyer.", preferredStyle: .alert)
        alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
        present(alert, animated: true, completion: nil)
        return
    }
    
    // 3
    let pdfCreator = PDFCreator(title: title, body: body, image: image, contact: contact)
    let pdfData = pdfCreator.createFlyer()
    let vc = UIActivityViewController(activityItems: [pdfData], applicationActivities: [])
    present(vc, animated: true, completion: nil)
  }
  
  @IBAction func selectImageTouched(_ sender: Any) {
    let actionSheet = UIAlertController(title: "Select Photo", message: "Where do you want to select a photo?", preferredStyle: .actionSheet)
    
    let photoAction = UIAlertAction(title: "Photos", style: .default) { (action) in
      if UIImagePickerController.isSourceTypeAvailable(.savedPhotosAlbum) {
        let photoPicker = UIImagePickerController()
        photoPicker.delegate = self
        photoPicker.sourceType = .photoLibrary
        photoPicker.allowsEditing = false
        
        self.present(photoPicker, animated: true, completion: nil)
      }
    }
    actionSheet.addAction(photoAction)
    
    let cameraAction = UIAlertAction(title: "Camera", style: .default) { (action) in
      if UIImagePickerController.isSourceTypeAvailable(.camera) {
        let cameraPicker = UIImagePickerController()
        cameraPicker.delegate = self
        cameraPicker.sourceType = .camera
        
        self.present(cameraPicker, animated: true, completion: nil)
      }
    }
    actionSheet.addAction(cameraAction)
    
    let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
    actionSheet.addAction(cancelAction)
    
    self.present(actionSheet, animated: true, completion: nil)
  }
  
  override func shouldPerformSegue(withIdentifier identifier: String, sender: Any?) -> Bool {
    if
      let _ = flyerTextEntry.text,
      let _ = bodyTextView.text,
      let _ = imagePreview.image,
      let _ = contactTextView.text {
      return true
    }
    
    let alert = UIAlertController(title: "All Information Not Provided", message: "You must supply all information to create a flyer.", preferredStyle: .alert)
    alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
    present(alert, animated: true, completion: nil)
    
    return false
  }
  
  override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "previewSegue" {
      guard let vc = segue.destination as? PDFPreviewViewController else { return }
      
      if let title = flyerTextEntry.text, let body = bodyTextView.text,
        let image = imagePreview.image, let contact = contactTextView.text {
        let pdfCreator = PDFCreator(title: title, body: body,
                                    image: image, contact: contact)
        vc.documentData = pdfCreator.createFlyer()
      }
    }
  }
}

extension FlyerBuilderViewController: UIImagePickerControllerDelegate {
  func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey: Any]) {
    
    guard let selectedImage = info[UIImagePickerController.InfoKey.originalImage] as? UIImage else {
      return
    }
    
    imagePreview.image = selectedImage
    imagePreview.isHidden = false
    
    dismiss(animated: true, completion: nil)
  }
}

extension FlyerBuilderViewController: UINavigationControllerDelegate {
  // Not used, but necessary for compilation
}

3. PDFCreator.swift

import UIKit
import PDFKit

class PDFCreator: NSObject {
  let title: String
  let body: String
  let image: UIImage
  let contactInfo: String
  
  init(title: String, body: String, image: UIImage, contact: String) {
    self.title = title
    self.body = body
    self.image = image
    self.contactInfo = contact
  }
  
  func createFlyer() -> Data {
    // 1
    let pdfMetaData = [
      kCGPDFContextCreator: "Flyer Builder",
      kCGPDFContextAuthor: "raywenderlich.com",
      kCGPDFContextTitle: title
    ]
    let format = UIGraphicsPDFRendererFormat()
    format.documentInfo = pdfMetaData as [String: Any]
    
    // 2
    let pageWidth = 8.5 * 72.0
    let pageHeight = 11 * 72.0
    let pageRect = CGRect(x: 0, y: 0, width: pageWidth, height: pageHeight)
    
    // 3
    let renderer = UIGraphicsPDFRenderer(bounds: pageRect, format: format)
    // 4
    let data = renderer.pdfData { (context) in
      // 5
      context.beginPage()
      // 6
      let titleBottom = addTitle(pageRect: pageRect)
      let imageBottom = addImage(pageRect: pageRect, imageTop: titleBottom + 18.0)
      addBodyText(pageRect: pageRect, textTop: imageBottom + 18.0)
      
      let context = context.cgContext
      drawTearOffs(context, pageRect: pageRect, tearOffY: pageRect.height * 4.0 / 5.0, numberTabs: 8)
      drawContactLabels(context, pageRect: pageRect, numberTabs: 8)
    }
    
    return data
  }
  
  func addTitle(pageRect: CGRect) -> CGFloat {
    // 1
    let titleFont = UIFont.systemFont(ofSize: 18.0, weight: .bold)
    // 2
    let titleAttributes: [NSAttributedString.Key: Any] =
      [NSAttributedString.Key.font: titleFont]
    let attributedTitle = NSAttributedString(string: title, attributes: titleAttributes)
    // 3
    let titleStringSize = attributedTitle.size()
    // 4
    let titleStringRect = CGRect(x: (pageRect.width - titleStringSize.width) / 2.0,
                                 y: 36, width: titleStringSize.width,
                                 height: titleStringSize.height)
    // 5
    attributedTitle.draw(in: titleStringRect)
    // 6
    return titleStringRect.origin.y + titleStringRect.size.height
  }

  func addBodyText(pageRect: CGRect, textTop: CGFloat) {
    // 1
    let textFont = UIFont.systemFont(ofSize: 12.0, weight: .regular)
    // 2
    let paragraphStyle = NSMutableParagraphStyle()
    paragraphStyle.alignment = .natural
    paragraphStyle.lineBreakMode = .byWordWrapping
    // 3
    let textAttributes = [
      NSAttributedString.Key.paragraphStyle: paragraphStyle,
      NSAttributedString.Key.font: textFont
    ]
    let attributedText = NSAttributedString(string: body, attributes: textAttributes)
    // 4
    let textRect = CGRect(x: 10, y: textTop, width: pageRect.width - 20,
                          height: pageRect.height - textTop - pageRect.height / 5.0)
    attributedText.draw(in: textRect)
  }

  func addImage(pageRect: CGRect, imageTop: CGFloat) -> CGFloat {
    // 1
    let maxHeight = pageRect.height * 0.4
    let maxWidth = pageRect.width * 0.8
    // 2
    let aspectWidth = maxWidth / image.size.width
    let aspectHeight = maxHeight / image.size.height
    let aspectRatio = min(aspectWidth, aspectHeight)
    // 3
    let scaledWidth = image.size.width * aspectRatio
    let scaledHeight = image.size.height * aspectRatio
    // 4
    let imageX = (pageRect.width - scaledWidth) / 2.0
    let imageRect = CGRect(x: imageX, y: imageTop,
                           width: scaledWidth, height: scaledHeight)
    // 5
    image.draw(in: imageRect)
    return imageRect.origin.y + imageRect.size.height
  }
  
  // 1
  func drawTearOffs(_ drawContext: CGContext, pageRect: CGRect,
                    tearOffY: CGFloat, numberTabs: Int) {
    // 2
    drawContext.saveGState()
    drawContext.setLineWidth(2.0)
    
    // 3
    drawContext.move(to: CGPoint(x: 0, y: tearOffY))
    drawContext.addLine(to: CGPoint(x: pageRect.width, y: tearOffY))
    drawContext.strokePath()
    drawContext.restoreGState()
    
    // 4
    drawContext.saveGState()
    let dashLength = CGFloat(72.0 * 0.2)
    drawContext.setLineDash(phase: 0, lengths: [dashLength, dashLength])
    // 5
    let tabWidth = pageRect.width / CGFloat(numberTabs)
    for tearOffIndex in 1..

后记

本篇主要讲述了基于PDFKit的PDF文档的创建和分享，感兴趣的给个赞或者关注~~~