Make the background of UIView a grid or a dot.

Here's how to make the UIView background a grid or a dot. This time, I created a subclass of UIView called GridView so that the dots can be switched by pressing a button.

GirdView

	import Foundation

	enum GridStyle {
	case none
	case grid
	case dot
	}

view raw GridStyle.swift hosted with ❤ by GitHub

	import UIKit

	class GridView: UIView {
	var gridStyle: GridStyle = .none
	let gridWidth: CGFloat = 20

	func setGrid(gridStyle: GridStyle) {
	self.gridStyle = gridStyle
	switch gridStyle {
	case .none:
	clear()

	case .grid:
	clear()
	drawGrid()

	case .dot:
	clear()
	drawDot()
	}
	}

	private func clear() {
	guard let layers = self.layer.sublayers else {
	return
	}
	for layer in layers {
	layer.removeFromSuperlayer()
	}
	}

	private func drawGrid() {
	let gridPath = UIBezierPath()

	// Horizontal
	var pointLeft = CGPoint(x: 0, y: gridWidth)
	var pointRight = CGPoint(x: bounds.size.width, y: gridWidth)
	while pointLeft.y < bounds.height {
	gridPath.move(to: pointLeft)
	gridPath.addLine(to: pointRight)
	pointLeft.y = pointLeft.y + gridWidth
	pointRight.y = pointRight.y + gridWidth
	}

	// Vertical
	var pointTop = CGPoint(x: gridWidth, y: 0)
	var pointBottom = CGPoint(x: gridWidth, y: bounds.size.height)
	while pointTop.x < bounds.width {
	gridPath.move(to: pointTop)
	gridPath.addLine(to: pointBottom)
	pointTop.x = pointTop.x + gridWidth
	pointBottom.x = pointBottom.x + gridWidth
	}

	let gridLayer = CAShapeLayer()
	gridLayer.frame = bounds
	gridLayer.path = gridPath.cgPath
	gridLayer.strokeColor = UIColor.black.cgColor
	gridLayer.lineWidth = 0.4
	layer.addSublayer(gridLayer)
	}

	private func drawDot() {
	let dotPath = UIBezierPath()
	var point = CGPoint(x: gridWidth, y: gridWidth)
	while point.x < bounds.width {
	while point.y < bounds.height {
	dotPath.move(to: point)
	dotPath.addArc(withCenter: point, radius: 1, startAngle: 0, endAngle: .pi * 2, clockwise: true)
	point.y = point.y + gridWidth
	}
	point.x = point.x + gridWidth
	point.y = gridWidth
	}

	let dotLayer = CAShapeLayer()
	dotLayer.frame = bounds
	dotLayer.path = dotPath.cgPath
	dotLayer.fillColor = UIColor.black.cgColor
	layer.addSublayer(dotLayer)
	}
	}

view raw GridView.swift hosted with ❤ by GitHub

	import UIKit

	class ViewController: UIViewController {
	var gridView: GridView = GridView()

	override func viewDidLoad() {
	super.viewDidLoad()

	gridView.frame = view.bounds
	view.addSubview(gridView)

	let button = UIButton()
	button.addTarget(self, action: #selector(changeGrid), for: .touchUpInside)
	button.setTitle("Tap Me!!", for: .normal)
	button.backgroundColor = .gray
	button.frame.size = CGSize(width: 100, height: 100)
	button.center = view.center
	view.addSubview(button)
	}

	@objc func changeGrid() {
	switch gridView.gridStyle {
	case .none:
	gridView.setGrid(gridStyle: .grid)
	case .grid:
	gridView.setGrid(gridStyle: .dot)
	case .dot:
	gridView.setGrid(gridStyle: .none)
	}
	}
	}

view raw ViewController.swift hosted with ❤ by GitHub