UIView Representative Does Not Conform to Protocol - swift

Question

I'm new to coding and am working on an app to display graphs using XCODE (13.1)/Swift. I want to be able to swipe to go from graph to graph, but have been unable to get it functioning. I originally tried to use a class to call for the swipe, but ran into conflicts with the UIView.
I think that the answer is to use a UIViewRepresentative, but I got an error that it did not conform to protocol. Here is the code for the approach using class (I have commented the options out as I have been troubleshooting.
/*class SwipeView: UIViewController{
override func viewDidLoad() {
super.viewDidLoad()
self.view.isUserInteractionEnabled = true
let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(tapForSwipe))
swipeRight.direction = .right
self.view.addGestureRecognizer(swipeRight)
let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(tapForSwipe))
swipeLeft.direction = .left
self.view.addGestureRecognizer(swipeLeft)
}
#objc private func tapForSwipe(sender : UISwipeGestureRecognizer){
if sender.direction == .right {
Charttype = Charttype - 1
print("right")
}
else if sender.direction == .left {
Charttype = Charttype + 1
return
}
if Charttype > 16 {
Charttype = 16
return
}
if Charttype < 0 {
Charttype = 0
return
}
And here is the code for the UIViewRepresentative approach:
enter
struct swipeGesture : UIViewRepresentable {
func makeCoordinator() -> swipeGesture.Coordinator {
return swipeGesture.Coordinator()
}
func makeUIView(context: UIViewControllerRepresentableContext<swipeGesture>) -> UIView{
let view = UIView()
let left = UISwipeGestureRecognizer(target :context.coordinator, action: #selector(context.coordinator.left))
left.direction = .left
let right = UISwipeGestureRecognizer(target: self, action: #selector(context.coordinator.right))
right.direction = .right
view.addGestureRecognizer(left)
view.addGestureRecognizer(right)
return view
}
func updateUIView(_ uiView: UIView, context: UIViewControllerRepresentableContext<swipeGesture>) {
}
class Coordinator : NSObject{
#objc func left(){
print("left")
}
#objc func right(){
print("right")
}
}
I appreciate any help and guidance on this. Thanks!

Answer 1

You're confusing UIViewControllerRepresentable and UIViewRepresentable. Your two function calls above need to be:
func updateUIView(_ uiView: UIView, context: Self.Context) {
and
func makeUIView(context: Self.Context) -> UIView {
You're using UIViewControllerRepresentableContext<swipeGesture> which is not relevant here, and the source of your problems. The error message you're seeing is that swipeGesture (should be SwipeGesture, by the way, types start with upper case letters) doesn't conform to UIViewControllerRepresentable, which is true. The compiler only thinks it should because you've mentioned it in the signature of these two methods.
The wider issue may be why you think this is a solution to your problem. UIViewRepresentable is for injecting UIKit views into a SwiftUI app, yet from your question it seems like you're building a UIKit app anyway, so I'm not sure why you're going this route. But that's a different question, I think.