I am using UIDocumentBrowser to retrieve files. But I am not able to place a back or cancel button in the navigation bar.
I want to make a cancellation button for this but I can't make a cancellation button. How can I solve this problem?
current code
~~~swift
import Foundation
import UIKit
@available(iOS 11.0, *)
class DocumentBrowserViewController : UIDocumentBrowserViewController, UIDocumentBrowserViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
browserUserInterfaceStyle = .dark
view.tintColor = .white
}
func documentBrowser(_ controller: UIDocumentBrowserViewController, didRequestDocumentCreationWithHandler importHandler: @escaping (URL?, UIDocumentBrowserViewController.ImportMode) -> Void) {
let newDocumentURL: URL? = nil
// Set the URL for the new document here. Optionally, you can present a template chooser before calling the importHandler.
// Make sure the importHandler is always called, even if the user cancels the creation request.
if newDocumentURL != nil {
importHandler(newDocumentURL, .move)
} else {
importHandler(nil, .none)
}
}
func documentBrowser(_ controller: UIDocumentBrowserViewController, didPickDocumentURLs documentURLs: [URL]) {
guard let sourceURL = documentURLs.first else { return }
do{
try presentDocument(at: sourceURL)
} catch {
Log.Debug("\(error)")
}
}
func documentBrowser(_ controller: UIDocumentBrowserViewController, didImportDocumentAt sourceURL: URL, toDestinationURL destinationURL: URL) {
// Present the Document View Controller for the new newly created document
do{
try presentDocument(at: sourceURL)
} catch {
Log.Debug("\(error)")
}
}
func documentBrowser(_ controller: UIDocumentBrowserViewController, failedToImportDocumentAt documentURL: URL, error: Error?) {
// Make sure to handle the failed import appropriately, e.g., by presenting an error message to the user.
}
func presentDocument(at documentURL: URL) throws {
guard documentURL.startAccessingSecurityScopedResource() else {
throw IXError.fileAcessFailed
}
let storyBoard = UIStoryboard(name: "Main", bundle: nil)
let documentViewController = storyBoard.instantiateViewController(withIdentifier: "ViewController") as! ViewController
documentViewController.document = Document(fileURL: documentURL)
}
}
~~~
picture of cancellation button that I want