Drag and drop to open window in SwiftUI app

It is a little trickier to do in SwiftUI but possible, though I have only tested this on visionOS. You can find the code below. You will also need to update your Info.plist and add NSUserActivityTypes array with your activities you want to open a new window.

import SwiftUI

struct Activity {
    static let openWindow = "com.ericlewis.openWindow"
}

struct ContentView: View {
    
    @State
    private var text = "root"
    
    var body: some View {
        Button(text) {
            // noop, makes it easier to grab and drag.
        }
        .onDrag {
            let payload = "destination payload \(Int.random(in: Int.min...Int.max))"
            
            let userActivity = NSUserActivity(activityType: Activity.openWindow)
            try! userActivity.setTypedPayload(["text": payload])
            let itemProvider = NSItemProvider(object: payload as NSString)
            itemProvider.registerObject(userActivity, visibility: .all)
            return itemProvider
        }
        .onContinueUserActivity(Activity.openWindow) { userActivity in
            if let dict = try? userActivity.typedPayload([String: String].self) {
                self.text = dict["text"]!
            }
        }
    }
}