Displaying the Day Of The Week From Date Picker

I want to store just the day of the week as a string using a datePicker in xcode using swift.

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var datePicker: UIDatePicker!
    @IBOutlet weak var strWeekday: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()

        // set mode to date only
        datePicker.datePickerMode = .date

        // add target for the trigger update function to change the weekday when the user changes the date
        datePicker.addTarget(self, action: #selector(triggerUpdate), for: .valueChanged)

        // weekday initial value
        strWeekday.text = datePicker.date.weekdayNameStandalone
    }

    @IBAction func triggerUpdate(_ datePicker: UIDatePicker) {
        strWeekday.text = datePicker.date.weekdayNameStandalone
    }
}

extension Date {

    // returns weekday name (Sunday-Saturday Localized) as String
    var weekdayNameStandalone: String {
        Formatter.weekdayNameStandalone.string(from: self)
    }

    // returns weekday name (Sunday-Saturday fixed locale en_US_POSIX) as String
    var weekdayNameStandAlonePosix: String {
        Formatter.weekdayNameStandAlonePosix.string(from: self)
    }

}

extension Formatter {

    static let weekdayNameStandalone: DateFormatter = {
        let formatter = DateFormatter()
        formatter.locale = .autoupdatingCurrent
        formatter.dateFormat = "cccc"
        return formatter
    }()

    static let weekdayNameStandAlonePosix: DateFormatter = {
        let formatter = DateFormatter()
        formatter.locale = .init(identifier: "en_US_POSIX")
        formatter.dateFormat = "cccc"
        return formatter
    }()
}