visionOS Freeform-style bottom toolbar ornament

VTBMainViewController.swift

//
//  VTBMainViewController.swift
//  VisionToolbar
//
//  Created by Steven Troughton-Smith on 21/07/2023.
//
//

import UIKit
import SwiftUI

struct CLPViewWrapper: UIViewRepresentable {
	var view: UIView
	
	func makeUIView(context: Context) -> some UIView {
		return view
	}
	
	func updateUIView(_ uiView: UIViewType, context: Context) {
		
	}
}

class VTBBarButtonItem: UIBarButtonItem {
	convenience init(symbolName:String) {
		let button = UIButton()
		button.configuration = .borderless()
		button.setImage(UIImage(systemName: symbolName), for: .normal)
		self.init(customView: button)
	}
}

class VTBBarDivider: UIView {
	
	override var isOpaque: Bool {
		get {
			return false
		}
		set {
			
		}
	}
	
	override func setNeedsLayout() {
		setNeedsDisplay()
	}
	
	override func draw(_ rect: CGRect) {
		let lineSize = CGFloat(2)
		UIColor.label.setFill()
		UIRectFill(CGRect(x: (bounds.width-lineSize)/2, y: 0, width: lineSize, height: bounds.height))
	}
	
	// MARK: -
	
	override var intrinsicContentSize: CGSize {
		return CGSize(width: 8.0, height: 34.0)
	}

	override func sizeThatFits(_ size: CGSize) -> CGSize {
		return intrinsicContentSize
	}
}

final class VTBMainViewController: UIViewController {
	
	let primaryToolbar = UIToolbar()
	
	init() {
		super.init(nibName: nil, bundle: nil)
		title = "VisionToolbar"
		
		view.backgroundColor = .white
		
		let a = VTBBarButtonItem(symbolName: "arrow.uturn.backward")
		let b = VTBBarButtonItem(symbolName: "arrow.uturn.forward")
		let c = UIBarButtonItem(customView: VTBBarDivider())
		let d = VTBBarButtonItem(symbolName: "pencil")
		let e = VTBBarButtonItem(symbolName: "eraser")
		let f = VTBBarButtonItem(symbolName: "theatermask.and.paintbrush")
		
		let s = UIBarButtonItem.fixedSpace(8)
		let x = UIBarButtonItem.fixedSpace(8)

		primaryToolbar.items = [x, a, s, b, .flexibleSpace(), c, s, d, s, e, s, f, x]
		primaryToolbar.layoutMargins = .zero
#if os(xrOS)
		setupOrnaments()
#endif
	}
	
	required init?(coder aDecoder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}
	
#if os(xrOS)
	override var preferredContainerBackgroundStyle: UIContainerBackgroundStyle {
		return .glass
	}
	
	func setupOrnaments() {
		
		let ornament = UIHostingOrnament(sceneAlignment:.bottom, contentAlignment:.center) {
			CLPViewWrapper(view: primaryToolbar)
				.frame(minWidth: 600, maxHeight: 40)
				.padding(.vertical)
				.glassBackgroundEffect()
		}
		
		ornaments = [ornament]
	}
#endif
	
}