private func setupNavigationBar() {
    navigationController?.navigationBar.isTranslucent = false
    let gradientLayer = CAGradientLayer()
    gradientLayer.frame.size = view.frame.size
    gradientLayer.startPoint = CGPoint(x:0.0, y:0.0)
    gradientLayer.endPoint = CGPoint(x:1.0, y:0.0)
    //gradient colors to be used in gradient of menu bar
    let blue = UIColor(red: 64/255.0, green: 100/255.0, blue: 142/255.0, alpha: 1.0)
    let red = UIColor(red: 145/255.0, green: 82/255.0, blue: 89/255.0, alpha: 1.0)
    //let middle = UIColor(red: 107/255.0, green: 94/255.0, blue: 122/255.0, alpha: 1.0)
    gradientLayer.colors = [blue.cgColor, red.cgColor]
    navigationController?.navigationBar.backgroundColor = gradientLayer
    let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 120, height: 40))
    imageView.widthAnchor.constraint(equalToConstant: 75.0).isActive = true
    let image = UIImage(named: "logo")
    imageView.image = image
    imageView.layer.cornerRadius = 10
    navigationItem.titleView = imageView

    let navButton = UIButton(frame: CGRect(x: 0, y: 0, width: 40, height: 10))
    let searchImage = UIImage(named: "side_menu")?.withRenderingMode(.alwaysOriginal)
    navButton.widthAnchor.constraint(equalToConstant: 32.0).isActive = true
    navButton.setBackgroundImage(searchImage, for: .normal)
    navButton.addTarget(self, action:  #selector(handleMore), for: .touchUpInside)
    navigationItem.leftBarButtonItem = UIBarButtonItem(customView: navButton)

}