Proof of concept. Индикатор загрузки для любого View

SuperviewMagic.swift

//: Playground - noun: a place where people can play

import UIKit

extension UIView {
    
    class Indicator: UIView {
        
    }
    
    func showIndicator() {
        guard let superview = superview else {
            print("Сначала добавьте кнопку")
            return
        }
        
        let buttonFrame = frame
        
        removeFromSuperview()
        
        let indicator = self.indicator()
        
        superview.addSubview(indicator)
        indicator.frame = CGRect(x: buttonFrame.minX, y: buttonFrame.minY, width: buttonFrame.width + 20, height: buttonFrame.height + 20)
        
        superview.addSubview(self)
        indicator.center = center
        
        //Если поругались констрейнты
        indicator.translatesAutoresizingMaskIntoConstraints = false
    }
    
    func hideIndicator() {
        let indicator = superview?.subviews.first(where: {$0 is Indicator})
        indicator?.removeFromSuperview()
    }
    
    
    func indicator() -> Indicator {
        let indicator = Indicator(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
        indicator.backgroundColor = UIColor.yellow
        return indicator
    }
}


let button = UIView(frame: CGRect(x: 30, y: 30, width: 40, height: 40))
button.backgroundColor = UIColor.blue
button.layer.cornerRadius = 20



var container = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
container.backgroundColor = UIColor.red

//Начинаем
container.addSubview(button)

container

button.showIndicator()

container

button.hideIndicator()

container