SwiftUI: Adjust bounds of ScrollView - swift

Question

I am trying to scale a view horizontally using scaleEffect and MagnificationGesture.
It is almost working as I want with the exception that the ScrollView does not resize when its child view resizes.
Is there a fix for this? Any solution would be greatly appreciated.
To reproduce:
run the code below
scale up the image horizontally with the pinch gesture
notice that the ScrollView scrolls as if the image still has the same size.
struct ContentView: View {
#State private var currentAmount: CGFloat = 0
#State private var finalAmount: CGFloat = 1
var body: some View {
ScrollView(.horizontal) {
Image(systemName: "star")
.resizable()
.scaledToFit()
.scaleEffect(x: finalAmount + currentAmount, y: 1)
.gesture(
MagnificationGesture()
.onChanged { amount in
self.currentAmount = amount - 1
}
.onEnded { amount in
self.finalAmount += self.currentAmount
self.currentAmount = 0
}
)
}
.frame(maxHeight: 300)
}
}

Answer 1

This view does it.
struct HorizontalScaleView<Content: View>: View {
#ViewBuilder var content: Content
#State private var currentAmount: CGFloat = 0
#State private var finalAmount: CGFloat = 1
var body: some View {
GeometryReader { geo in
ScrollView(.horizontal) {
content
.scaledToFit()
.scaleEffect(x: finalAmount + currentAmount, y: 1)
.frame(width: (finalAmount + currentAmount) * geo.size.width, height: geo.size.width)
.gesture(
MagnificationGesture()
.onChanged { amount in
self.currentAmount = amount - 1
}
.onEnded { _ in
if self.finalAmount + self.currentAmount >= 1 {
self.finalAmount += self.currentAmount
} else {
self.finalAmount = 1
}
self.currentAmount = 0
}
)
}
}
}
}