請有人幫忙。一旦用戶單擊 pdf 查看器上的共享按鈕，我想添加一條警報訊息，我正在使用 UIDocumentInteractionController 預覽 pdf 檔案。我想知道是否有任何可以覆寫的委托方法或函式，在打開共享表之前我可以在哪里添加警報？[！[在此處輸入影像描述][1]][1]
class ViewController: UIViewController {
var documentController : UIDocumentInteractionController!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
@IBAction private func buttonTapped(_ sender: Any) {
guard let fileURL = Bundle.main.url(forResource: "infomation", withExtension: "pdf") else {return}
documentController = UIDocumentInteractionController.init(url: fileURL)
documentController.delegate = self
documentController.presentPreview(animated: true)
}
}
extension ViewController: UIDocumentInteractionControllerDelegate {
func documentInteractionControllerViewControllerForPreview(_ controller: UIDocumentInteractionController) -> UIViewController {
return self
}
func documentInteractionControllerWillPresentOpenInMenu(_ controller: UIDocumentInteractionController) {
}
func documentInteractionControllerWillPresentOptionsMenu(_ controller: UIDocumentInteractionController) {
}
func documentInteractionController(_ controller: UIDocumentInteractionController, willBeginSendingToApplication application: String?) {
}
}
但是當我單擊共享按鈕時，它們都沒有被呼叫，即使我已將委托設定為我的視圖控制器。有沒有辦法可以做到這一點？
uj5u.com熱心網友回復：
解釋：
如果不通過迭代所有子視圖并覆寫按鈕的動作和目標來將其組合在一起，就沒有辦法做到這一點。
一種干凈的方法是創建自己的預覽控制器，如下所示。如果您添加QLPreviewControllerto UINavigationController，它會自動創建一個bottom toolbar您不想要的。要解決此問題，請將其添加為常規的子控制器UIViewController并創建自定義導航欄。
您還可以使用UTI來UIActivityItem確定如何共享專案。我只實作了預覽和基本的共享功能，但其余的應該非常容易做到，而且至少它比UIDocumentInteractionController你完全控制一切更可定制。
現在對于執行所有這些的代碼：
//
// ViewController.swift
// CustomDocumentController
//
// Created by brandon on 2022-01-13.
//
import UIKit
import QuickLook
import MobileCoreServices
import UniformTypeIdentifiers
private class PreviewItem: NSObject, QLPreviewItem {
var previewItemURL: URL?
var previewItemTitle: String?
init(title: String, url: URL) {
super.init()
previewItemURL = url
previewItemTitle = title
}
}
class DocumentInteractionController: UIViewController {
private let url: URL
private lazy var navigationBar: UINavigationBar = {
let navigationBar = UINavigationBar()
let navigationItem = UINavigationItem(title: name ?? "Document")
navigationItem.hidesBackButton = true
navigationItem.leftBarButtonItem = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(onDone))
navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(onShare)) //UIImage(systemName: "square.and.arrow.up")
navigationBar.pushItem(navigationItem, animated: false)
return navigationBar
}()
private lazy var previewController: QLPreviewController = {
let previewController = QLPreviewController()
previewController.title = name
previewController.dataSource = self
previewController.delegate = self
previewController.reloadData()
return previewController
}()
var uti: String? {
didSet {
previewController.reloadData()
}
}
var name: String? {
didSet {
previewController.title = name
navigationBar.topItem?.title = name
}
}
init(url: URL) {
self.url = url
super.init(nibName: nil, bundle: nil)
//super.init(rootViewController: self.previewController)
self.modalPresentationStyle = .fullScreen
name = (try? url.resourceValues(forKeys: [.localizedNameKey]))?.localizedName
uti = (try? url.resourceValues(forKeys: [.typeIdentifierKey]))?.typeIdentifier
if uti == nil {
if #available(iOS 15.0, *) {
uti = UTType.url.identifier
} else {
uti = String(kUTTypeURL)
}
}
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func viewDidLoad() {
super.viewDidLoad()
addChild(previewController)
previewController.didMove(toParent: self)
let separator = UIView()
separator.backgroundColor = .lightGray
view.addSubview(navigationBar)
view.addSubview(separator)
view.addSubview(previewController.view)
NSLayoutConstraint.activate([
navigationBar.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
navigationBar.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor),
navigationBar.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor),
separator.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
separator.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor),
separator.topAnchor.constraint(equalTo: navigationBar.bottomAnchor),
separator.heightAnchor.constraint(equalToConstant: 1.0 / UIScreen.main.scale),
previewController.view.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
previewController.view.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor),
previewController.view.topAnchor.constraint(equalTo: separator.bottomAnchor),
previewController.view.bottomAnchor.constraint(equalTo: view.bottomAnchor)
])
[navigationBar, separator, previewController.view].forEach({
$0?.translatesAutoresizingMaskIntoConstraints = false
})
navigationBar.barTintColor = previewController.view.backgroundColor
view.backgroundColor = previewController.view.backgroundColor
}
}
extension DocumentInteractionController: QLPreviewControllerDelegate, QLPreviewControllerDataSource {
func numberOfPreviewItems(in controller: QLPreviewController) -> Int {
return 1
}
func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem {
return PreviewItem(title: name ?? "Document", url: url)
}
}
extension DocumentInteractionController {
@objc
private func onDone() {
self.dismiss(animated: true, completion: nil)
}
@objc
private func onShare() {
let activityViewController = UIActivityViewController(activityItems: [url],
applicationActivities: nil)
activityViewController.excludedActivityTypes = [.assignToContact]
if UIDevice.current.userInterfaceIdiom == .pad {
activityViewController.popoverPresentationController?.sourceView = self.view
}
self.present(activityViewController, animated: true, completion: nil)
}
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let url = Bundle.main.url(forResource: "Testing", withExtension: ".md")
let doc = DocumentInteractionController(url: url!)
DispatchQueue.main.asyncAfter(deadline: .now() 2.0) {
self.present(doc, animated: true, completion: nil)
}
}
}
截圖：
轉載請註明出處，本文鏈接：https://www.uj5u.com/shujuku/410979.html
標籤：
上一篇：如何在貓鼬中填充物件陣列