File sharing using UIActivityViewController/ UIDocumentInteractionController not working - [can't share via AirDrop, Whatapp, iMessage, Mail, etc.]

Question

While trying to share an '.mp3' file that I have downloaded onto my app using the device's share-sheet feature, I'm able to fetch the file from the documents directory but unable to share it.

When I try to share it via Whatsapp, I get an error saying:

This item cannot be shared. Please select a different item.

If I share via AirDrop, it just says "Failed" (in red) and sharing via other options leads to a blank message (eg a new email with no file attached or a new msg with nothing in it)

Here are the code options I've tried so far:

Option 1 - Using UIActivityViewController

let fileURL = NSURL(fileURLWithPath: FileURLFromDocumentsDirectory)

var filesToShare = [Any]()

filesToShare.append(fileURL)

let activityViewController = UIActivityViewController(activityItems: filesToShare, applicationActivities: nil)

self.present(activityViewController, animated: true, completion: nil)

Option 2 - Using UIDocumentInteractionController

let docController : UIDocumentInteractionController?
docController = UIDocumentInteractionController(url: URL(string: fileToSharePath)!)
docController?.delegate = self
docController?.presentOptionsMenu(from: self.view.frame, in:self.view, animated:true)

In both options, I do get the file but can't share it. The phone does recognize the share as an audio file but I can't do anything with it.

Sample URL:

file:///Users/UserName/Library/Developer/CoreSimulator/Devices/C8B09E62-091F-4E61-BA6C-3D9EC23LKC01/data/Containers/Data/Application/EF2CKKJF-AB35-55G5-B778-439812EFGGG5/Documents/audioFile.mp3

The sharing works for text but not for the audio files.

Do I also need to enable some features or add some code to the AppDelegate?

Appreciate any help. Thanks.

Update #1: Code with Suggestions from @dfd [still doesn't work]

let shareAction = UIContextualAction(style: .normal, title: "Share") { (action, view, completionHandler) in
            
    let fileURL = NSURL(fileURLWithPath: (downloadedFile?.documentDirectoryURL)!)

    let activityViewController = UIActivityViewController(activityItems: [fileURL], applicationActivities: nil)

    self.present(activityViewController, animated: true, completion: nil)
                
}

Also, for all these options, I get the audio file (mp3) as an 'Audio Recording' in the Share Sheet.

Answer 1

Instead of sharing the original file, can you try to create a copy of this in a temporary directory and share that copy. Once done with sharing you can delete or leave it to the system to delete it.

Something like this (You can add more check about file and directory existance):

let fileManager = FileManager.default
let tempDirectory = fileManager.temporaryDirectory
let tempPath = tempDirectory.path + "/" + fileToSharePath.lastPathComponent
let tempURL = URL(fileURLWithPath: tempPath)
try? fileManager.copyItem(atPath:fileToSharePath.path , toPath: tempPath)


let docController : UIDocumentInteractionController?
docController = UIDocumentInteractionController(url: URL(string: tempURL)!)
docController?.delegate = self
docController?.presentOptionsMenu(from: self.view.frame, in:self.view, animated:true)