JavaFX: Попытка отобразить текст в метках, в новом окне, после нажатия кнопки

Question

Я пытаюсь создать оконную программу, используя JavaFx и SceneBuilder. По какой-то причине я не могу получить текст, который я sh должен отображать в последнем окне после нажатия кнопки. Окно открывается, но текст никогда не отображается и не применяется к моим ярлыкам. Я получаю исключение Nullpointer для моего метода displayTime, я не понимаю, почему. Вот код для моего класса контроллера, а также файл F XML для моего последнего окна.

package plan;

import java.io.IOException;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.stage.Stage;

public class MainController{

    @FXML
    public String act1, act2, act3, act4;

    @FXML
    public Button input;

    @FXML
    public Button proceed;

    @FXML
    public Button start;

    @FXML
    public Button calcTime;

    @FXML
    public TextField task1;
    @FXML
    public TextField task2;
    @FXML
    public TextField task3;
    @FXML
    public TextField task4;
    @FXML
    public TextField hours;

    @FXML
    public Label fplan1;
    @FXML
    public Label fplan2;
    @FXML
    public Label fplan3;
    @FXML
    public Label fplan4;
    @FXML
    public Label timesCalc;


    @FXML
    private void startPlan(ActionEvent event) throws IOException{
        Stage primaryStage = new Stage();
        Parent root = FXMLLoader.load(getClass().getResource("NewPlan.fxml"));
        Scene scene = new Scene(root); //creation of a scene
        primaryStage.setScene(scene);
        primaryStage.setTitle("YOUR DAILY PLAN");
        primaryStage.show();// Displays window/ stage 
        Stage currentStage =  (Stage)start.getScene().getWindow();
        currentStage.close();

    }

    @FXML
    private void inputDay(ActionEvent event)throws IOException {

        Stage currentStage =  (Stage)input.getScene().getWindow();
        currentStage.close();

        Stage primaryStage = new Stage();
        Parent root = FXMLLoader.load(getClass().getResource("NormalDay.fxml"));
        Scene scene = new Scene(root); //creation of a scene
        primaryStage.setScene(scene);
        primaryStage.setTitle("YOUR DAILY PLAN");
        primaryStage.show();// Displays window/ stage

    }

    @FXML
    private void calcTime(ActionEvent event)throws IOException {


        Day day = new Day(Integer.parseInt(hours.getText()));

        act1 = "Time you have for " + task1.getText() + " is " + Integer.toString(day.getT(1)) + " hours " + Integer.toString(day.getT(11));
        act2 = "Time you have for " + task2.getText() + " is " + Integer.toString(day.getT(2)) + " hours " + Integer.toString(day.getT(22));
        act3 = "Time you have for " + task3.getText() + " is " + Integer.toString(day.getT(3)) + " hours " + Integer.toString(day.getT(33));
        act4 = "Time you have for " + task4.getText() + " is " + Integer.toString(day.getT(4)) + " hours " + Integer.toString(day.getT(44));

        timesCalc.setText("Time Calculation Completed!");

        //TIMES CALCULATED MESSAGE
    }

    @FXML
    private void displayTime(ActionEvent event)throws IOException {

        Stage primaryStage = new Stage();
        Parent root = FXMLLoader.load(getClass().getResource("FinalDay.fxml"));
        Scene scene = new Scene(root); //creation of a scene
        primaryStage.setScene(scene);
        primaryStage.setTitle("YOUR DAILY PLAN");
        primaryStage.show();// Displays window/ stage

        fplan1.setText("TEST");
        fplan2.setText(act2);
        fplan3.setText(act3);
        fplan4.setText(act3);

        //ANOTHER display method??? times still wont show on final page after continue button



    }



}

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.HBox?>
<?import javafx.scene.layout.VBox?>
<?import javafx.scene.text.Font?>


<AnchorPane prefHeight="500.0" prefWidth="700.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/8.0.171" fx:controller="plan.MainController">
   <children>
      <HBox alignment="CENTER" layoutY="14.0" prefHeight="100.0" prefWidth="704.0">
         <children>
            <Label text="YOUR PLAN" textFill="#3751e8">
               <font>
                  <Font name="System Italic" size="36.0" />
               </font>
            </Label>
         </children>
      </HBox>
      <VBox layoutX="11.0" layoutY="121.0" prefHeight="378.0" prefWidth="683.0" spacing="50.0">
         <children>
            <Label fx:id="fplan1" prefHeight="35.0" prefWidth="762.0">
               <font>
                  <Font size="24.0" />
               </font>
            </Label>
            <Label fx:id="fplan2" prefHeight="35.0" prefWidth="700.0">
               <font>
                  <Font size="24.0" />
               </font>
            </Label>
            <Label fx:id="fplan3" prefHeight="35.0" prefWidth="957.0">
               <font>
                  <Font size="24.0" />
               </font>
            </Label>
            <Label fx:id="fplan4" prefHeight="35.0" prefWidth="734.0">
               <font>
                  <Font size="24.0" />
               </font>
            </Label>
         </children>
      </VBox>
   </children>
</AnchorPane>