Initial position of a SwiftUI view - swift

Question

I have a view that gets dragged around the screen by updating its position. I'm having a hard time setting its initial position via an argument.
I'm trying to use the commented out var initialPosition argument.
struct FloatingView<Content:View>: View {
let content: Content
var hidden: Bool
var size: CGSize
// var initialPosition: CGPoint
#State private var location: CGPoint = CGPoint(x:65, y:100)
var simpleDrag: some Gesture {
DragGesture()
.onChanged { value in
self.location = value.location
}
}
var body: some View {
if hidden == false {
content
.foregroundColor(.pink)
// .frame(width: 100, height: 100)
.position(location)
.gesture(simpleDrag)
}
}
}

Answer 1

It is possible to do this in view's init, like
struct FloatingView<Content:View>: View {
private let content: Content
private let hidden: Bool
private let size: CGSize
#State private var location: CGPoint
init(content: Content, hidden: Bool, size: CGSize, initialPosition: CGPoint) {
self.content = content
self.hidden = hidden
self.size = size
self._location = State(initialValue: initialPosition) // << here !!
}
// ...
}

Answer 2

You could use a GeometryReader in order to read the frame of the View, get its center & assign it to initialPosition.
Try this:
struct FloatingView<Content:View>: View {
let content: Content
var hidden: Bool
var size: CGSize
#State var initialPosition: CGPoint
#State private var location: CGPoint = CGPoint(x:65, y:100)
var simpleDrag: some Gesture {
DragGesture()
.onChanged { value in
self.location = value.location
}
}
var body: some View {
GeometryReader { proxy in
if hidden == false {
content
.foregroundColor(.pink)
//.frame(width: 100, height: 100)
.position(location)
.gesture(simpleDrag)
.onAppear {
initialPosition = proxy.frame(in: .global).center
}
}
}
}
}