adds swipe-left-to-dismiss

SwipeBackModifier.swift

import SwiftUI
import UIKit

/// A ViewModifier that re-enables the default iOS edge-swipe back gesture in a SwiftUI NavigationStack.
struct SwipeBackModifier: ViewModifier {
    func body(content: Content) -> some View {
        content
            .background(SwipeBackEnabler().frame(width: 0, height: 0).allowsHitTesting(false))
    }
}

extension View {
    /// Re-enable the interactive pop (edge-swipe) gesture on NavigationStack.
    func enableSwipeBack() -> some View {
        modifier(SwipeBackModifier())
    }
}

// MARK: - UIKit Representable to hook into UINavigationController
private struct SwipeBackEnabler: UIViewControllerRepresentable {
    func makeUIViewController(context: Context) -> UIViewController {
        let vc = UIViewController()
        DispatchQueue.main.async {
            vc.navigationController?.interactivePopGestureRecognizer?.delegate = context.coordinator
            vc.navigationController?.interactivePopGestureRecognizer?.isEnabled = true
        }
        return vc
    }

    func updateUIViewController(_ uiViewController: UIViewController, context: Context) {}

    func makeCoordinator() -> Coordinator { Coordinator() }

    class Coordinator: NSObject, UIGestureRecognizerDelegate {
        func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool { true }

        func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer,
                               shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
            true
        }
    }
}