Show a SwiftUI View floating above another View without altering its layout.

Above.swift

import SwiftUI

extension View {
	func float<Content: View>(above: Content) -> ModifiedContent<Self, Above<Content>> {
		self.modifier(Above(aboveContent: above))
	}
}

struct Above<AboveContent: View>: ViewModifier {
	let aboveContent: AboveContent

	func body(content: Content) -> some View {
		content.overlay(
			GeometryReader { proxy in
				Rectangle().fill(Color.clear).overlay(
					self.aboveContent.offset(x: 0, y: -proxy.size.height),
					alignment: .bottom
				)
			},
			alignment: .bottom
		)
	}
}