📥 Seamless Background Downloads in SwiftUI

Handling file downloads in the background is a common requirement for iOS apps — especially those dealing with large files or when users move away from the app. In this guide, you’ll learn how to implement a background file downloader using SwiftUI and URLSession, and ensure downloaded files are moved to a permanent location even if the app is terminated.

🧱 Key Concepts

Before diving in, here’s what we’re going to implement:

• Background downloads using URLSessionDownloadTask.
• Handling file moves to a permanent storage location (Documents directory).
• Resuming app state after download completion (even post-termination).
• Integrating everything smoothly in a SwiftUI project.

🔧 Step 1: Create a Download Manager

We begin by creating a singleton DownloadManager class that configures a URLSession for background tasks, handles download delegation, and moves files after download.

import Foundation
class DownloadManager: NSObject, ObservableObject, URLSessionDownloadDelegate {
    static let shared = DownloadManager()
private var backgroundSession: URLSession!
private override init() {
        super.init()
        let config =…