I'm trying to migrate all my SpriteKit code into a SwiftUI SpriteView container. My program is a mix of SwiftUI and SpriteKit on MacOS to trade crypto.
The problem I'm having is that the scrollWheel(with event: NSEvent)
function inside my SKScene object isn't getting triggered when I scroll my mouse wheel.
Previously I solved this by making the SKScene the nextResponder which worked great when I was using Cocoa.
Below is what my main entry point to SwiftUI looks like.
@main
struct ManualTradingApp: App {
var exchangeManger: ExchangeManager = BinanceManager()
var chartScene: ChartScene {
let scene = ChartScene(size: CGSize(width: 600, height: 600), manager: exchangeManger)
scene.scaleMode = .resizeFill
return scene
}
var body: some Scene {
WindowGroup {
ContentView(manager: exchangeManger, chartScene: chartScene)
}
}
}
Here is the function inside of the ChartScene class I made that is supposed to receive the scroll wheel events.
override func scrollWheel(with event: NSEvent) {
if chartNode.contains(event.locationInWindow) {
chartNode.scrollWheel(with: event)
} else if chartNode2.contains(event.locationInWindow) {
chartNode2.scrollWheel(with: event)
}
if symbolRowContainer.contains(event.locationInWindow) {
moveSymbolContainer(deltaY: -event.scrollingDeltaY * 10.0)
}
}
you can capture scrollWheel events via an NSView, then post them as notifications, which can be received by the SKScene.
first add a notification observer to your SKScene
class GameSceneScrollWheel: SKScene {
override func didMove(to view: SKView) {
NotificationCenter.default.addObserver(self,
selector: #selector(self.scrollWheelWithEvent(notification:)),
name: Notification.Name("scrollWheelWithEvent"),
object: nil)
}
//receive notification and passthrough to normal `scrollWheel` function
@objc func scrollWheelWithEvent(notification: Notification) {
guard let event = notification.object as? NSEvent else { return }
self.scrollWheel(with:event)
}
override func scrollWheel(with event: NSEvent) {
print("event.deltaY: \(event.deltaY)") //success!
}
}
second, intercept events in NSView and post a notification
struct ScrollWheelEventView : NSViewRepresentable {
class ScrollWheelView : NSView {
override var acceptsFirstResponder: Bool { true }
override func acceptsFirstMouse(for event: NSEvent?) -> Bool { return true }
override func scrollWheel(with event: NSEvent) {
NotificationCenter.default.post(name: Notification.Name("scrollWheelWithEvent"), object: event)
}
}
func makeNSView(context: Context) -> some NSView {
return ScrollWheelView()
}
func updateNSView(_ nsView: NSViewType, context: Context) {}
}
and finally, add the NSViewRepresentable to SwiftUI
struct ScrollWheel: View {
@State private var scene = GameSceneScrollWheel()
var body: some View {
ZStack {
SpriteView(scene: scene)
ScrollWheelEventView()
}
}
}