File Export from iOS - eventually import too

No, you don't need to write the data as a file to your the app’s document directory. With UIActivityViewController, you can share a piece of text, as shown in the following code example

let text =  "This is a piece of text."
let activityViewController = UIActivityViewController(activityItems: [text], applicationActivities: nil)

With that, when activityViewController is presented, it shows the system-provided share UI that contains a Save to Files button, which allows you to save the text as a file to iCloud Drive. Tapping the button shows a UI that has a Save as field for you to input the file name for the taget file.

To import a file, consider using SwiftUI fileImporter.

Best,
——
Ziqiao Chen
 Worldwide Developer Relations.

Thanks for these answers, but I'm afraid I need a bit more help. How do you go about presenting the activityViewController? Could you show this in a small example app?

I had previously written this and it does share but it creates 2 files, and doesn't present any way to rename the file.

import SwiftUI
import UIKit

struct ContentView: View {
    @State private var showShareSheet = false
    @State private var textItem1 = ""
    @State private var textItem2 = ""
    
//    @State private var shareItems: [Any] = [
//      "Check out this file!",
//      URL(fileURLWithPath: FileManager.documentsDirectory.path()) // Replace with a real file URL
//    ]
    
var shareItems: [Any] {
    [   textItem1,
          textItem2
//          URL(fileURLWithPath: "TinySavedItems")
        ]
}
    var body: some View {
        VStack {
            TextField("enter text", text: $textItem1)
                .padding()
            TextField("enter text", text: $textItem2)
                .padding()
          
            Button("Share", systemImage: "square.and.arrow.up") {
              showShareSheet = true
            }
            .sheet(isPresented: $showShareSheet) {
                ActivityViewController(activityItems: shareItems)
            }
        }
    }
    
    struct ActivityViewController: UIViewControllerRepresentable {
        
        // Items to share (e.g., text, URLs, files)
        let activityItems: [Any]
        // Custom activities (optional)
        let applicationActivities: [UIActivity]? = nil
        // Completion handler (optional)
        @Environment(\.dismiss) var dismiss
        
        // Create the UIActivityViewController
        func makeUIViewController(context: Context) -> UIActivityViewController {
            
            let vc = UIActivityViewController(
                activityItems: activityItems,
                applicationActivities: applicationActivities
            )
            vc.excludedActivityTypes = [
                .postToFacebook, .postToTwitter
            ]
            // Handle completion (e.g., dismiss after sharing)
            vc.completionWithItemsHandler = { _, success, _, error in
                if success || error != nil {
                    dismiss() // Close the sheet after sharing
                }
            }
            return vc
        }
        func updateUIViewController(_ uiViewController: UIActivityViewController, context: Context) {} //doesn't do anything but is required
    }
}