//an example for stack overflow answer. http://stackoverflow.com/questions/26689731/xcode-doesnt-load-a-custom-view

errorView

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        ErrorView.errorInView(self.view, animated: true)
    }
}

class ErrorView: UIView {

    class func errorInView(view:UIView, animted:Bool) -> ErrorView {
        println("ERROR VIEW LOADED")
        //let errorView = ErrorView(frame: view.bounds)
        var errorView = ErrorView(frame: view.bounds)
        errorView.backgroundColor = UIColor.greenColor()
        errorView.opaque = false
        view.addSubview(errorView)
        return errorView
    }
}