HomeController.java

package app;

import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.stage.Stage;

import java.awt.event.ActionEvent;
import java.io.IOException;

public class HomeController {
    @FXML
    private Label middle;

    public void clickLeftButton() {
        middle.setText("The button on the left was clicked.");
    }

    public void clickRightButton() {
        middle.setText("The button on the right was clicked.");
    }

    public void clickBottomButton() {
        middle.setText("This is the starter text.");
    }

    public void switchScreen(javafx.event.ActionEvent event) throws IOException {
        Parent parent = FXMLLoader.load(getClass().getResource("secondScreen.fxml"));
        Scene scene = new Scene(parent);

        Stage window = (Stage)((Node)event.getSource()).getScene().getWindow();

        window.setScene(scene);
        window.show();
    }
}