QLPreviewController customisation

Hi everyone,

I’m trying to customise look of the QLPreviewController.
Problem is it’s not default look of it, because global appearance of UINavigationBar, UIBarButtonItem, UITabBar are changed in app delegate.

To change tint color of navigation bar I subclassed QLPreviewController and in viewDidLoad() did this:

self.navigationController?.navigationBar.tintColor = nil

It comes back to default blue color. This is how it looks right now and what I would like to change.

I tried to change barTintColor same as I changed back button tint color but it didn’t worked.
This is how I’m opening QLPreviewController

viewController.pushViewController(self, animated: true)
import Foundation
import QuickLook

class DocumentPreviewer: QLPreviewController, QLPreviewControllerDataSource, QLPreviewControllerDelegate {
	var fileURL: URL?

	override func viewDidLoad() {
		self.navigationController?.navigationBar.tintColor = nil

	func openDocument(vc: UIViewController, document: Document?) {

		guard let document = document else {
			print("Cannot open document because it's nil")

		if let navController = vc.navigationController {
			navController.pushViewController(self, animated: true)
		} else {
			vc.show(self, sender: nil)

		API.sharedInstance.fetchDocument(document) { (saved) in
			DispatchQueue.main.async(execute: {
				guard let url = saved else {
					print("File url is not valid")
				if QLPreviewController.canPreview(url as QLPreviewItem) {
					self.currentPreviewItemIndex = 0
					self.fileURL = url
					self.dataSource = self
					self.delegate = self

				} else {
					makeDefaultAlert(self, title: "Not supported", msg: "File is not supported for preview")
					print("Item not supported by QLPreviewController")

	func numberOfPreviewItems(in controller: QLPreviewController) -> Int {
		return 1

	func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem {
		return fileURL as! QLPreviewItem

And this is how I’m calling it

let docpreview = DocumentPreviewer()
docpreview.openDocument(vc: self, document: document)

Thanks for help,