ButtonStateExample.swift

class VC: UIViewController {

  private let asyncButton = UIButton()

  func doAsyncAction() {
    // Change button to display loading when we click on it
    asyncButton.isEnabled = false
    asyncButton.setTitle("Loading", for: .disabled)
    asyncButton.setTitleColor(.red, for: .disabled)
    networkManager.makeRequest() { response in 
      // Do network stuff
      // Sets button title text and color back to original for .normal
      // Notice we don't need to call setTitle / setTitleColor again
      DispatchQue.main.async {  
       self.asyncButton.isEnabled = true
      }
    }

}