如何更改条形图颜色。
谁能给我一个线索：
如何设置线条图的颜色？
如何将css类设置为series？

public class hmw3 extends Application {

@Override public void start(Stage stage) throws Exception{

        stage.setTitle("HİSTOGRAM");

        final CategoryAxis xAxis = new CategoryAxis();

        final NumberAxis yAxis = new NumberAxis(0,50,10);

        final BarChart<String,Number> bc = 
            new BarChart<String,Number>(xAxis,yAxis);

        bc.setTitle("HİSTOGRAM");

        final VBox verticalbox = new VBox();

        final HBox horizontalbox = new HBox();

        final Button draw = new Button("DRAW");

        CheckBox red = new CheckBox("RED");

        red.setSelected(true);

        CheckBox blue = new CheckBox("BLUE");

        final TextField textfield = new TextField();

        horizontalbox.setAlignment(Pos.BOTTOM_RIGHT);

        horizontalbox.setSpacing(46);

        String filename = textfield.getText();

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

        bc.setPrefSize(800, 600);

        horizontalbox.getChildren().addAll(draw, red, blue,textfield);

        verticalbox.getChildren().addAll(bc, horizontalbox);

        horizontalbox.setPadding(new Insets(10, 10, 10, 50));

        Scene scene  = new Scene(new Group());

        ((Group)scene.getRoot()).getChildren().add(verticalbox);

        stage.setScene(scene);

        stage.show();

                //Setting the button on action if its clicked
        draw.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent event) {         
                try {
                hmw34.occur(textfield.getText(), series1); 
                bc.getData().add(series1);
                bc.setLegendVisible(false);
                } catch (FileNotFoundException e) {
                    System.out.println("Error : No such file"); 
                }
            }
        });

        // rengini düzenleyecek.

    /**if (red.isSelected()) 
       bc.setStyle("-fx-bar-fill: #000080;"); // red box checked

      else if (blue.isSelected()) 
         bc.setStyle("-fx-bar-fill: #b22222;");// The Blue check box checked*/

    }

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