How to search a PDF using PDFkit in Swift - swift

Question

My goal is to search for a string and then go to it. I have these three lines of code needed to implement it. I just know my thought process for getting there is missing something. I am not sure how to use .findstring. I read that it returns an array of PDFSelections. But I am not sure how to use that to use .setCurrentSelection using the PDFSelection array.
let found = document.findString(selection, withOptions: .caseInsensitive)
let stringSelection = page?.selection(for: NSRange(location:10, length:5))
pdfView.setCurrentSelection(stringSelection, animate: true)

Answer 1

Create SearchTableViewController ViewController :
import UIKit
import PDFKit
protocol SearchTableViewControllerDelegate: class {
func searchTableViewController(_ searchTableViewController: SearchTableViewController, didSelectSerchResult selection: PDFSelection)
}
class SearchTableViewController: UITableViewController {
open var pdfDocument: PDFDocument?
weak var delegate: SearchTableViewControllerDelegate?
var searchBar = UISearchBar()
var searchResults = [PDFSelection]()
override func viewDidLoad() {
super.viewDidLoad()
tableView.rowHeight = 150
searchBar.delegate = self
searchBar.showsCancelButton = true
searchBar.searchBarStyle = .minimal
navigationItem.titleView = searchBar
navigationItem.leftBarButtonItem = UIBarButtonItem(barButtonSystemItem: .cancel,
target: self,
action: #selector(closeBtnClick))
tableView.register(UINib(nibName: "SearchViewCell", bundle: nil), forCellReuseIdentifier: "SearchViewCell")
}
#objc func closeBtnClick(sender: UIBarButtonItem) {
dismiss(animated: false, completion: nil)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
searchBar.becomeFirstResponder()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return searchResults.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "SearchViewCell", for: indexPath) as! SearchViewCell
let selection = searchResults[indexPath.row]
let page = selection.pages[0]
let outline = pdfDocument?.outlineItem(for: selection)
let outlintstr = outline?.label ?? ""
let pagestr = page.label ?? ""
let txt = outlintstr + " 页码: " + pagestr
cell.destinationLabel.text = ""
let extendSelection = selection.copy() as! PDFSelection
extendSelection.extend(atStart: 10)
extendSelection.extend(atEnd: 90)
extendSelection.extendForLineBoundaries()
let range = (extendSelection.string! as NSString).range(of: selection.string!, options: .caseInsensitive)
let attrstr = NSMutableAttributedString(string: extendSelection.string!)
attrstr.addAttribute(NSAttributedStringKey.backgroundColor, value: UIColor.yellow, range: range)
cell.resultTextLabel.attributedText = attrstr
return cell
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let selection = searchResults[indexPath.row]
delegate?.searchTableViewController(self, didSelectSerchResult: selection)
dismiss(animated: false, completion: nil)
}
override func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
searchBar.resignFirstResponder()
}
}
extension SearchTableViewController: UISearchBarDelegate {
func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
searchBar.resignFirstResponder()
}
func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
pdfDocument?.cancelFindString()
dismiss(animated: false, completion: nil)
}
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
// if searchText.count < 2 {
// return
// }
searchResults.removeAll()
tableView.reloadData()
pdfDocument?.cancelFindString()
pdfDocument?.delegate = self
pdfDocument?.beginFindString(searchText, withOptions: .caseInsensitive)
}
}
extension SearchTableViewController: PDFDocumentDelegate {
func didMatchString(_ instance: PDFSelection) {
searchResults.append(instance)
tableView.reloadData()
}
}
On Search Button Tap :
let searchViewController = SearchTableViewController()
searchViewController.pdfDocument = self.pdfdocument
searchViewController.delegate = self
let nav = UINavigationController(rootViewController: searchViewController)
self.present(nav, animated: false, completion:nil)
You will get highlighted text in :
func searchTableViewController(_ searchTableViewController: SearchTableViewController, didSelectSerchResult selection: PDFSelection) {
selection.color = UIColor.yellow
self.pdfview.currentSelection = selection
self.pdfview.go(to: selection)
calculateStandByMood()
}
Just add this protocol in pdfViewController :
SearchTableViewControllerDelegate

Answer 2

I think you can reach to the current selection using
pdfView.go(to selection: pdView.currentSelection)
According to this doc, PDF can be navigated using selection, destination and rect
https://developer.apple.com/documentation/pdfkit/pdfview/1505172-go