Custom loading button with custom state with FLAnimatedImage (for showing gif data)

LoadingButton.swift

import UIKit
import FLAnimatedImage

@IBDesignable
open class LoadingButton: UIButton {
    // MARK: - General Properties
    public enum State: Int {
        case initial
        case loading
        case finished
    }
    
    @IBInspectable open var imageAlpha: CGFloat = 1.0 {
        didSet {
            if let imageView = imageView {
                imageView.alpha = imageAlpha
            }
        }
    }
    @IBInspectable var borderColorStart: UIColor = .aloMediumBlue
    @IBInspectable var borderColorFinished: UIColor = .aloGreyishTwo
    @IBInspectable var startText: String = "Default"
    @IBInspectable var finishedText: String = "Default"
    @IBInspectable var textColorStart: UIColor = .aloMediumBlue
    @IBInspectable var textColorFinished: UIColor = .aloGreyishTwo
    @IBInspectable var gifData: String = "icon-loading-blue"
    @IBInspectable var initialImage: UIImage? {
        didSet {
            self.imageView?.image = initialImage
        }
    }
    @IBInspectable var finishedImage: UIImage?
    private var stateButton: State = .initial
    
    lazy private var activityIndicator: FLAnimatedImageView = {
        let imageView = FLAnimatedImageView()
        return imageView
    }()
    
    private var action: (() -> Void)?
    
    // MARK: - Lifecycle
    open override func awakeFromNib() {
        super.awakeFromNib()
        setupActivityIndicator()
        self.addTarget(self, action: #selector(tapped), for: .touchUpInside)
    }
    
    override open func layoutSubviews() {
        super.layoutSubviews()
        switch stateButton {
        case .initial:
            setInitialView()
            break
        case .loading:
            setLoadingView()
            break
        case .finished:
            setFinishedView()
            break
        }
        self.imageView?.alpha = imageAlpha
    }
    
    // MARK: - Methods
    open func touchUpInside(action: (() -> Void)? = nil) {
        self.action = action
    }
    
    func setState(state: State) {
        stateButton = state
        self.setNeedsLayout()
    }
    
    @objc func tapped(sender: LoadingButton) {
        self.action?()
    }
    
    private func setInitialView() {
        DispatchQueue.main.async { [weak self] in
            guard let self = self else { return }
            self.isUserInteractionEnabled = true
            UIView.animate(withDuration: 0.3, animations: { [weak self] in
                guard let self = self else { return }
                self.activityIndicator.alpha = 0.0
                self.titleLabel?.alpha =  1.0
                self.imageAlpha = 1
                self.setTitle(self.startText, for: .normal)
                self.setTitleColor(self.textColorStart, for: .normal)
                self.setImage(self.initialImage, for: .normal)
                self.layer.borderColor = self.borderColorStart.cgColor
            })
        }
    }
    
    private func setLoadingView() {
        self.isUserInteractionEnabled = false
        UIView.animate(withDuration: 0.3, animations: { [weak self] in
            guard let self = self else { return }
            self.titleLabel?.alpha = 0.0
            self.imageAlpha = 0.0
            self.activityIndicator.alpha = 1.0
            self.layer.borderColor = self.borderColorStart.cgColor
        })
    }
    
    private func setFinishedView() {
        DispatchQueue.main.async { [weak self] in
            guard let self = self else { return }
            self.isUserInteractionEnabled = true
            UIView.animate(withDuration: 0.3, animations: { [weak self] in
                guard let self = self else { return }
                self.activityIndicator.alpha = 0.0
                self.titleLabel?.alpha =  1.0
                self.imageAlpha = 1
                self.setTitle(self.finishedText, for: .normal)
                self.setTitleColor(self.textColorFinished, for: .normal)
                self.setImage(self.finishedImage, for: .normal)
                self.layer.borderColor = self.borderColorFinished.cgColor
            })
        }
    }
    
    private func setupActivityIndicator() {
        activityIndicator.translatesAutoresizingMaskIntoConstraints = false
        self.addSubview(activityIndicator)
        activityIndicator.setCenterXYWithSuperview()
        activityIndicator.setWidth(29)
        activityIndicator.setHeight(29)
        activityIndicator.animatedImage = FLAnimatedImage(gifResource: gifData)
        activityIndicator.alpha = 0.0
    }
}