Drag-Drop file into the application icon (MacOS GUI app)

I was testing out the drag-drop feature in MacOS with a GUI app (uses SwiftUI framework).

I have modified Info.plist file to accept any file on drag-drop.

<key>CFBundleDocumentTypes</key>
    <array>
        <dict>
            <key>CFBundleTypeExtensions</key>
            <array>
                <string>*</string>
            </array>
        </dict>
    </array>

DragDropV3App.swift

class AppDelegate: NSObject, NSApplicationDelegate {
    func applicationDidFinishLaunching(_ notification: Notification) {
        print("hello")
        
        // C function which writes the passed argument (in this case, the string, "Hello") to a log file.
        PrintToFile("Hello");
    }
    
    func application(_ sender: NSApplication, openFile filename: String) -> Bool {
            
        PrintToFile ("File open func called!");
    
        return true
    }
}
    

@main
struct DragDropV3App: App {
    
    @NSApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

When I drag and drop a file into the .app icon, the application launches and "Hello" string is written to log file, but the string - "File open func called!", is not present in the file. The application:openFile is not called when the file is drag-dropped.

To understand basic swift, I have followed the official documentation. Some of the links I referred during this exercise are,

1. Basic Template of SwiftUI
2. Add AppDelegate to SwiftUI app
3. application:openFile

I have also checked other stackoverflow answers (like this) to check if this is right way. The application:openFile seems to be the right function.

Do let me know where I went wrong. Thank you.