How to get a JavaFX XYchart to work with user defined CSS?

I am currently learning JavaFX.scene.charts. I am using Netbeans 7.4. I have read various tutorials on Oracle, but I cannot find exactly how they use CSS files with JavaFX XYcharts. It shows standalone CSS and JavaFX files not both being represented at the same time.

http://docs.oracle.com/javafx/2/charts/css-styles.htm

http://docs.oracle.com/javafx/2/charts/scatter-chart.htm

above are links that describe how to make the css files and the scatter XYcharts. And I know that I'm supposed to do something like below in my JavaFX file to get my style sheet to work.

scene.getStylesheets().add("myfirstscatterchart/Scatter.css");

I'm getting a warning saying that it cannot find my style sheet when I run my chart.

They are in the same location path wise.

C:\Users\user\Documents\NetBeansProjects\MyFirstScatterChart\src\myfirstscatterchart\Scatter.css C:\Users\user\Documents\NetBeansProjects\MyFirstScatterChart\src\myfirstscatterchart\MyFirstScatterChart.java

I had tried using the absolute path, but that did not work. So I'm not sure what I am doing wrong here.

below is code I took from the Oracle website to run and I made the small modification of scene.getStylesheets().add("myfirstscatterchart/Scatter.css"); near the bottom. Is there anything blaringly obvious that I did to my code? I think it's a path issue, but I'm not sure how to fix it.

I've also found that I am having a similar problem to the one listed here:

Loading css using JavaFX null pointer exception in eclipse

I added a try/catch block and it printed out the exception I was having and it said a null pointer exception. Also it does print this warning:

Note: C:\Users\elizabeth.mcclellan\Documents\NetBeansProjects\SecondScatter\src\secondscatter\SecondScatter.java uses unchecked or unsafe operations.

Note: Recompile with -Xlint:unchecked for details.

However this question was never fully answered. I tried both answer suggestions mentioned and neither worked in my case.

import javafx.application.Application;

import javafx.geometry.Insets;

import javafx.scene.Group;

import javafx.scene.Scene;

import javafx.scene.chart.NumberAxis;

import javafx.scene.chart.ScatterChart;

import javafx.scene.chart.XYChart;

import javafx.scene.control.Button;

import javafx.scene.layout.HBox;

import javafx.scene.layout.VBox;

import javafx.stage.Stage;

public class MyFirstScatterChart extends Application {

@Override public void start(Stage stage) {
    stage.setTitle("Scatter Chart Sample");
    final NumberAxis xAxis = new NumberAxis(0, 10, 1);
    final NumberAxis yAxis = new NumberAxis(-100, 500, 100);        
    final ScatterChart<Number,Number> sc = 
        new ScatterChart<Number,Number>(xAxis,yAxis);
    xAxis.setLabel("Age (years)");                
    yAxis.setLabel("Returns to date");
    sc.setTitle("Investment Overview");



    XYChart.Series series1 = new XYChart.Series();

    series1.setName("Option 1");
    series1.getData().add(new XYChart.Data(4.2, 193.2));
    series1.getData().add(new XYChart.Data(2.8, 33.6));
    series1.getData().add(new XYChart.Data(6.2, 24.8));
    series1.getData().add(new XYChart.Data(1, 14));
    series1.getData().add(new XYChart.Data(1.2, 26.4));
    series1.getData().add(new XYChart.Data(4.4, 114.4));
    series1.getData().add(new XYChart.Data(8.5, 323));
    series1.getData().add(new XYChart.Data(6.9, 289.8));
    series1.getData().add(new XYChart.Data(9.9, 287.1));
    series1.getData().add(new XYChart.Data(0.9, -9));
    series1.getData().add(new XYChart.Data(3.2, 150.8));
    series1.getData().add(new XYChart.Data(4.8, 20.8));
    series1.getData().add(new XYChart.Data(7.3, -42.3));
    series1.getData().add(new XYChart.Data(1.8, 81.4));
    series1.getData().add(new XYChart.Data(7.3, 110.3));
    series1.getData().add(new XYChart.Data(2.7, 41.2));

    sc.setPrefSize(500, 400);
    sc.getData().addAll(series1);
    Scene scene  = new Scene(new Group());

    final VBox vbox = new VBox();
    final HBox hbox = new HBox();

    final Button add = new Button("Add Series");               
    final Button remove = new Button("Remove Series");

    hbox.setSpacing(10);
    hbox.getChildren().addAll(add, remove);

    vbox.getChildren().addAll(sc, hbox);
    hbox.setPadding(new Insets(10, 10, 10, 50));

    ((Group)scene.getRoot()).getChildren().add(vbox);
    stage.setScene(scene);
    scene.getStylesheets().add("myfirstscatterchart/Scatter.css"); 
    stage.show();
}

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

Solution

I discovered my own answer. Three conditions must be met to use a JavaFX file and a CSS file together:

both JavaFX file and CSS file must both be in same directory

You must declare in your code you are using the CSS file such as

  scene.getStylesheets().add(MyFirstScatterChart.class.getResource("Scatter.css").toExternalForm());

And the thing I was doing wrong you must have package PackageName; such as:

package MyFirstScatterChart;.
This will be at the top of your JavaFX file you define your chart.