Subclassing QLPreviewController inside a UITabBarController does not show edit option of PDF - ios

Question

I am trying to present QLPreviewController as one of the Tab in a Tabview contorller. It able to show PDF properly but pencilkit/Markup not shown
Reason: i want to show PencilKit to draw on the PDF and save it (other type of files from local or network also hence QL), also capture highlights from PDF(others)
Xcode 12.3
Swift 5
iOS/iPAD: 14
problem:
Q1) Unable to view Markup or edit button at the stop of PDF files. Tried hiding tab bar and subviews are always nil. Any help is appreciated.
Q2) Is it possible to override Highlight sector/function in menuItem (on PDF i see nice options so want to use it however want to save the text selection)?
class QLPreviewController2: QLPreviewController {
var toolbars: [UIView] = []
var observations : [NSKeyValueObservation] = []
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
}
}
extension QLPreviewController2: QLPreviewControllerDelegate {
func previewController(_ controller: QLPreviewController, editingModeFor previewItem: QLPreviewItem) -> QLPreviewItemEditingMode {
return .updateContents
}
func previewController(_ controller: QLPreviewController, shouldOpen url: URL, for item: QLPreviewItem) -> Bool {
return true
}
func previewController(_ controller: QLPreviewController, didUpdateContentsOf previewItem: QLPreviewItem) {
}
func previewController(_: QLPreviewController, didSaveEditedCopyOf: QLPreviewItem, at: URL) {
}
}
And my TabVC is
class TabVC: UITabBarController, UITabBarControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
guard let viewcontollers = viewControllers else {
return
}
let item1 = QLPreviewController2()
item1.dataSource = self
// self.navigationItem.rightBarButtonItems?.append(item1.editButtonItem) //did not work
item1.isEditing = true //did not work
item1.setEditing(true, animated: true)//did not work
let icon1 = UITabBarItem(title: "Title", image: UIImage(named: "doc"), selectedImage: UIImage(named: "doc"))
item1.tabBarItem = icon1
self.viewControllers!.append(item1)
// navigationItem.leftBarButtonItems?.append(item1.editButtonItem) //did not work
}
//Delegate methods
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
print("Should select viewController: \(viewController.title ?? "") ?")
return true;
}
}
extension TabVC: QLPreviewControllerDataSource {
func numberOfPreviewItems(in: QLPreviewController) -> Int {
return 1
}
func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem {
print("2")
let fileUrl = Bundle.main.url(forResource: "some", withExtension: ".pdf", subdirectory: nil, localization: nil)
let filePreview = PreviewItem2()
filePreview.previewItemURL = fileUrl
return filePreview
}
}

Answer 1

For solving first problem you should embed your QLPreviewController into the UINavigationController and this will consequently show UINavigationBar over QLPreviewController along with bar button items. Then you must append this UINavigationController instance to viewControllers instance property of the UITabBarController.
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
//...
let item1 = QLPreviewController2()
let nc = UINavigationController(rootViewController: item1)
//...
self.viewControllers!.append(nc)
}
Second problem is hard to define because of your english, but I'm guessing you want some custom functionality which can't be achieved by QuickLook framework.