SnackBar.swift

import UIKit

class SnackBar: UIView {

    @IBOutlet weak var titleLabel: UILabel!
    
    static var newInstance: SnackBar {
        return Bundle.main.loadNibNamed("SnackBar",
                                        owner: nil,
                                        options: nil)!.first as! SnackBar
    }
    
    func configure(message: String) {
        self.titleLabel.text = message
    }

}


extension UIViewController {    
    
    func showSnackBar(msg: String, delay: TimeInterval = 0.6) {
        guard let window = appDelegate.window else { return }
        let bounds = window.bounds
        let snackBar = SnackBar.newInstance
        snackBar.configure(message: msg)
        snackBar.frame = CGRect(x: 0.0,
                                y: 0.0,
                                width: bounds.width,
                                height: 64.0)
        snackBar.alpha = 0
        window.addSubview(snackBar)
        window.bringSubview(toFront: snackBar)
        UIView.animate(withDuration: 0.5, animations: {
            snackBar.alpha = 1
        }) { _ in
            UIView.animate(withDuration: 0.5, delay: delay, animations: {
                snackBar.alpha = 0
            }) { _ in
                snackBar.removeFromSuperview()
            }
        }
    }
    
}