Can’t figure out why I’m getting this error. I’ve seen similar questions on the internet, but basically all the examples deal with images, what am I doing wrong?
my code:
struct OffsetModifier: ViewModifier {
@Binding var offset: CGFloat
var returnFromStart: Bool = true
@State var startValue: CGFloat = 0
func body(content: Content) -> some View {
content
.overlay {
GeometryReader { proxy in
Color.clear
.preference(key: OffsetKey.self, value: proxy.frame(in: .named("SCROLL")).midY)
.onPreferenceChange(OffsetKey.self) { value in
if startValue == 0 {
startValue = value
}
offset = (value - (returnFromStart ? startValue : 0))
}
}
}
}
}
struct OffsetKey: PreferenceKey {
static var defaultValue: CGFloat = 0
static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
value = nextValue()
}
}