viewAllButton.setOnAction(event -> {
try {
FXMLLoader loader = new FXMLLoader(getClass().getResource(“search_results.fxml”));
Parent searchResultsRoot = loader.load();

            // Get the controller and set the toner data
            SearchResultsController controller = loader.getController();
            controller.setTonerData(tonerData);

            Stage searchResultsStage = new Stage();
            searchResultsStage.setTitle("View All Toners");
            searchResultsStage.setScene(new Scene(searchResultsRoot, 800, 600));
            searchResultsStage.initModality(Modality.WINDOW_MODAL);
            searchResultsStage.initOwner(primaryStage);
            searchResultsStage.show();

            TableView<PrinterToner> searchResultsTable = (TableView<PrinterToner>) searchResultsRoot.lookup("#search_results");
            searchResultsTable.setItems(tonerData);

            searchResultsTable.setOnMouseClicked(event1 -> {
                if (event1.getClickCount() == 2 && !searchResultsTable.getSelectionModel().isEmpty()) {
                    PrinterToner selectedToner = searchResultsTable.getSelectionModel().getSelectedItem();
                    openTonerPopup(selectedToner);
                }
            });
        } catch (IOException e) {
            e.printStackTrace();
        }
    });

When i run my application and click on the view all button i get a java.lang.NullPointerException on the controller

Exception in thread “JavaFX Application Thread” java.lang.NullPointerException: Cannot invoke “com.example.toner_inventory.SearchResultsController.setTonerData(javafx.collections.ObservableList)” because “controller” is null
at com.example.toner_inventory/com.example.toner_inventory.App.lambda$start$2(App.java:64)

this is my searchResultsController

package com.example.toner_inventory;

import javafx.collections.ObservableList;
import javafx.fxml.FXML;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;

public class SearchResultsController {

    @FXML
    private TableView<PrinterToner> search_results;
    @FXML
    private TableColumn<PrinterToner, String> serialNumberCol;
    @FXML
    private TableColumn<PrinterToner, String> locationCol;
    @FXML
    private TableColumn<PrinterToner, String> colorCol;
    @FXML
    private TableColumn<PrinterToner, String> checkoutDateCol;

    @FXML
    public void initialize() {
        serialNumberCol.setCellValueFactory(new PropertyValueFactory<>("serialNumber"));
        locationCol.setCellValueFactory(new PropertyValueFactory<>("location"));
        colorCol.setCellValueFactory(new PropertyValueFactory<>("color"));
        checkoutDateCol.setCellValueFactory(new PropertyValueFactory<>("checkoutDate"));
    }

    public void setTonerData(ObservableList<PrinterToner> tonerData) {
        search_results.setItems(tonerData);
    }
}