MessageViewController.swift

extension ViewController: MFMessageComposeViewControllerDelegate {
    func showMessageComposeViewController() {
        guard MFMessageComposeViewController.canSendText() else {
            print("SMS services are not available")
            return
        }

        let messageComposeViewController = MFMessageComposeViewController()
        messageComposeViewController.messageComposeDelegate = self
        messageComposeViewController.body = "Your text here"
        present(messageComposeViewController, animated: true)
    }

    func messageComposeViewController(_ controller: MFMessageComposeViewController, didFinishWith result: MessageComposeResult) {
        controller.dismiss(animated: true, completion: nil)
    }
}