JavaFX入门及相关问题

import java.net.URL;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.ResourceBundle;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;

public class MyController implements Initializable {

    @FXML
    private Button myButton;

    @FXML
    private TextField myTextField;

    @Override
    public void initialize(URL location, ResourceBundle resources) {

        // TODO (don‘t really need to do anything here).

    }

    // When user click on myButton
    // this method will be called.
    public void showDate() {                    //之前这里的代码是public void showDateTime(ActionEvent event) 但是系统一直报错event not use，
                                                //后来误打误撞把ActionEvent event删了，程序就能运行了，明天再看看是什么原因

        System.out.println("Button Clicked!");

        Date now= new Date();

        DateFormat df = new SimpleDateFormat("yyyy-dd-MM HH:mm:ss");
        String dateTimeString = df.format(now);
        // Show in VIEW
        myTextField.setText(dateTimeString);

    }

}

import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {
        try {
            // Read file fxml and draw interface.
            Parent root = FXMLLoader.load(getClass().getResource("/MyScene.fxml"));

            primaryStage.setTitle("My Application");
            primaryStage.setScene(new Scene(root));
            primaryStage.show();

        } catch(Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        launch(args);
    }
}