The UIViewRepresentable code does not work as outlined in Chapter 4. The binding give all sorts of errors. This is how I solved the problem and it is now working. I reference the ColorUISlider in the Coordinator by way of a parent variable and then I can assign the slider value to the bound value variable.
struct ColorUISlider: UIViewRepresentable {
var color: UIColor
@Binding var value:Double
class Coordinator: NSObject {
let parent:ColorUISlider
init(parent:ColorUISlider) {
self.parent = parent
}
@objc func valueChanged(_ sender: UISlider) {
self.parent.value = Double(sender.value)
}
}
func makeCoordinator() -> ColorUISlider.Coordinator {
Coordinator(parent: self)
}
func makeUIView(context: Context) -> UISlider {
let slider = UISlider(frame: .zero)
slider.thumbTintColor = color
slider.value = Float(value)
slider.addTarget(context.coordinator, action: #selector(Coordinator.valueChanged(_:)), for: .valueChanged)
return slider
}
func updateUIView(_ uiView: UISlider, context: Context) {
uiView.value = Float(value)
}
}
struct ColorUISlider_Previews: PreviewProvider {
static var previews: some View {
ColorUISlider(color: .red, value: .constant(0.5))
}
}
