Playground简单色条动画

import UIKit
import XCPlayground

let showView = UIView(frame: CGRect(x: 0, y: 0, width: 300, height: 300))
showView.backgroundColor = UIColor.black

let rectangle1 = UIView(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
let rectangle2 = UIView(frame: CGRect(x: 0, y: 50, width: 50, height: 50))
let rectangle3 = UIView(frame: CGRect(x: 0, y: 100, width: 50, height: 50))
let rectangle4 = UIView(frame: CGRect(x: 0, y: 150, width: 50, height: 50))
let rectangle5 = UIView(frame: CGRect(x: 0, y: 200, width: 50, height: 50))
let rectangle6 = UIView(frame: CGRect(x: 0, y: 250, width: 50, height: 50))

rectangle1.backgroundColor = UIColor.red
rectangle2.backgroundColor = UIColor.orange
rectangle3.backgroundColor = UIColor.yellow
rectangle4.backgroundColor = UIColor.green
rectangle5.backgroundColor = UIColor.blue
rectangle6.backgroundColor = UIColor.purple
showView.addSubview(rectangle6)
showView.addSubview(rectangle5)
showView.addSubview(rectangle4)
showView.addSubview(rectangle3)
showView.addSubview(rectangle2)
showView.addSubview(rectangle1)

UIView.animate(withDuration: 2){
    rectangle1.backgroundColor = UIColor.purple
    rectangle1.frame = CGRect(x: 250, y: 50, width: 50, height: 150)
    rectangle2.backgroundColor = UIColor.blue
    rectangle2.frame = CGRect(x: 200, y: 100, width: 50, height: 150)
    rectangle3.backgroundColor = UIColor.green
    rectangle3.frame = CGRect(x: 150, y: 50, width: 50, height: 150)
    rectangle4.backgroundColor = UIColor.yellow
    rectangle4.frame = CGRect(x: 100, y: 100, width: 50, height: 150)
    rectangle5.backgroundColor = UIColor.orange
    rectangle5.frame = CGRect(x: 50, y: 50, width: 50, height: 150)
    rectangle6.backgroundColor = UIColor.red
    rectangle6.frame = CGRect(x: 0, y: 100, width: 50, height: 150)
}

XCPlaygroundPage.currentPage.liveView = showView