ios - Send tapAction from SwiftUI button action to UIView function

Question

I'm trying to find a way to trigger an action that will call a function in my UIView when a button gets tapped inside swiftUI.

Here's my setup:

foo()(UIView) needs to run when Button(SwiftUI) gets tapped

My custom UIView class making use of AVFoundation frameworks

class SomeView: UIView {

    func foo() {}
}

To use my UIView inside swiftUI I have to wrap it in UIViewRepresentable

struct SomeViewRepresentable: UIViewRepresentable {

    func makeUIView(context: Context) -> CaptureView {
        SomeView()
    }

    func updateUIView(_ uiView: CaptureView, context: Context) {        
    }
}

SwiftUI View that hosts my UIView()

struct ContentView : View {

    var body: some View {
        VStack(alignment: .center, spacing: 24) {
            SomeViewRepresentable()
                .background(Color.gray)
            HStack {
                Button(action: {
                    print("SwiftUI: Button tapped")
                   // Call func in SomeView()
                }) {
                    Text("Tap Here")
                }
            }
        }
    }
}

Answer 1

You can store an instance of your custom UIView in your representable struct (SomeViewRepresentable here) and call its methods on tap actions:

struct SomeViewRepresentable: UIViewRepresentable {

  let someView = SomeView() // add this instance

  func makeUIView(context: Context) -> SomeView { // changed your CaptureView to SomeView to make it compile
    someView
  }

  func updateUIView(_ uiView: SomeView, context: Context) {

  }

  func callFoo() {
    someView.foo()
  }
}

And your view body will look like this:

  let someView = SomeViewRepresentable()

  var body: some View {
    VStack(alignment: .center, spacing: 24) {
      someView
        .background(Color.gray)
      HStack {
        Button(action: {
          print("SwiftUI: Button tapped")
          // Call func in SomeView()
          self.someView.callFoo()
        }) {
          Text("Tap Here")
        }
      }
    }
  }

To test it I added a print to the foo() method:

class SomeView: UIView {

  func foo() {
    print("foo called!")
  }
}

Now tapping on your button will trigger foo() and the print statement will be shown.