Create buttons in a navigationController's UIToolbar using Swift 3

Toolbar.swift

 if let nav = navigationController {
            
            nav.setToolbarHidden(false, animated: false)
         
            // doesn't really set the button's tint
            UIToolbar.appearance().tintColor = UIColor.black
            
            // instead of setting the text color of each bar button
            UIBarButtonItem.appearance().tintColor = UIColor.black
            
            //http://www.fileformat.info/info/unicode/char/26ed/index.htm
            let settingsButton = UIBarButtonItem(title: "\u{2699}",
                                                 style: .plain,
                                                 target: self,
                                                 action: #selector(TracksViewController.settings))
            
            let peace = UIBarButtonItem(title: "\u{262E}",
                                        style: .plain,
                                        target: self,
                                        action: #selector(TracksViewController.settings))
            
            // from the musical symbol block, not the misc symbol block
            let eighth = UIBarButtonItem(title: "\u{1D160}",
                                         style: .plain,
                                         target: self,
                                         action: #selector(TracksViewController.settings))
            
            toolbarItems = [settingsButton, peace, eighth]
            
            // or
            self.navigationItem.setRightBarButtonItems([settingsButton, peace, eighth], animated: true)
            self.navigationItem.setLeftBarButtonItems([settingsButton, peace, eighth], animated: true)
}