我有一个小程序，它连接数据库以获取数据并在StackedBarChart中显示。在我插入数据之前，我会为每天和客户排序。我也有一个ComboBox，让用户选择一天。 因此每次更改日期时，我都会清除图表数据并添加新数据。然后我想动态更改颜色，因为我不知道将显示多少客户。我知道在演出舞台后我必须这样做。 在程序开始时，第一个图表显示了它们看起来正确。堆叠条和图例的颜色已更改，不会重复。但如果我选择另一天，传奇的颜色不会改变并显示相同的八种颜色，重复的是八个以上的顾客。 这是我的一段代码：
public class BarChartSample extends Application
{
StackPane chartPane;
StackPane comboboxPane;
BorderPane layout;
Scene scene;
StackedBarChart<String, Number> bc;
ComboBox<String> combobox;
ArrayList<Date> listDates;
ArrayList<Customer> listCustomers;
HashMap<String, ArrayList<XYChart.Series<String, Number>>> listData;
ArrayList<Day> listDays;
ObservableList<String> xCategories =
FXCollections.<String> observableArrayList("6", "7", "8", "9", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19");
StackedBarChart<String, Number> chart;
@Override
public void start(Stage stage) throws Exception
{
try
{
boolean dataExists = getDataSortedByDay();
if (dataExists)
{
stage.setTitle("Title");
ArrayList<String> weekdays = dateToWeekday(listDates);
CategoryAxis xAxis = new CategoryAxis();
NumberAxis yAxis = new NumberAxis();
xAxis.setLabel("Lieferstunde");
xAxis.setCategories(xCategories);
yAxis.setLabel("Anzahl Dokumente");
chart = new StackedBarChart<String, Number>(xAxis, yAxis);
chart.setAnimated(false);
chart.applyCss();
listData = new HashMap<String, ArrayList<XYChart.Series<String, Number>>>();
// create for every day a new chart and save to hashmap
for (Day day : listDays)
{
// create for every customer of a day a new series
ArrayList<XYChart.Series<String, Number>> listSeries = new ArrayList<XYChart.Series<String, Number>>();
for (Customer customer : day.getListCustomers())
{
XYChart.Series<String, Number> series = new XYChart.Series<String, Number>();
series.setName(customer.getName());
series.getData().add(new XYChart.Data<String, Number>(String.valueOf(customer.getHour()), customer.getNumDocs()));
listSeries.add(series);
}
listData.put(dateToWeekday(day.getDate()), listSeries);
}
chartPane = new StackPane();
chart.getData().addAll(listData.get(weekdays.get(0)));
chartPane.getChildren().add(chart);
comboboxPane = new StackPane();
comboboxPane.getChildren().add(createComboBoxMenu(weekdays));
layout = new BorderPane();
layout.setTop(comboboxPane);
layout.setCenter(chartPane);
scene = new Scene(layout, 1000, 800);
stage.setScene(scene);
stage.centerOnScreen();
stage.show();
chart.setTitle(weekdays.get(0));
changeColorsOfChart(chart);
}
else
{
// no data found
}
}
catch (ClassNotFoundException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (SQLException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (Exception e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public ComboBox<String> createComboBoxMenu(ArrayList<String> weekdays)
{
ContextMenu contextMenu = new ContextMenu();
for (String date : weekdays)
{
MenuItem menuItem = new MenuItem(date);
contextMenu.getItems().add(menuItem);
}
combobox = new ComboBox<String>(FXCollections.<String> observableArrayList(weekdays));
combobox.setContextMenu(contextMenu);
combobox.valueProperty().addListener(new ChangeListener<String>()
{
@Override
public void changed(ObservableValue<? extends String> ov, String oldValue, String newValue)
{
chart.getData().clear();
chart.getData().addAll(listData.get(newValue));
changeColorsOfChart(chart);
}
});
return combobox;
}
public void changeColorsOfChart(StackedBarChart<String, Number> chart)
{
ArrayList<Color> listColors = new ArrayList<Color>();
for (int i = 0; i < chart.getData().size(); i++)
{
Set<Node> seriesNodes = chart.lookupAll(".series" + i);
String rgb = randomColorRgbFormat();
while (listColors.contains(rgb))
{
rgb = randomColorRgbFormat();
}
for (Node n : seriesNodes)
{
n.setStyle("-fx-background-color: rgb(" + rgb + "); ");
}
}
}
public String randomColorRgbFormat()
{
Color color = new Color(Math.random(), Math.random(), Math.random(), 0);
return String.format("%d, %d, %d, 1.0", (int) (color.getRed() * 255), (int) (color.getGreen() * 255),
(int) (color.getBlue() * 255));
}
public static void main(String[] args)
{
launch(args);
}
我已经在stackoverflow和其他网站上查了很多，并找到了jewelseas的例子。但是，当数据总是在变化时，我无法解决问题。 如果您需要更多信息来帮助我，请告诉我们！
答案 0 :(得分：0)
感谢Sedrick Jefferson。他的链接解决了这个问题。 这是我改变颜色的新代码：
public void changeColorsOfChart(StackedBarChart<String, Number> chart)
{
ArrayList<Color> listColors = new ArrayList<Color>();
HashMap<String, String> colors = new HashMap<String, String>();
for (XYChart.Series<String, Number> series : chart.getData())
{
String rgb = randomColorRgbFormat();
while (listColors.contains(rgb))
{
rgb = randomColorRgbFormat();
}
for (XYChart.Data<String, Number> data : series.getData())
{
data.getNode().setStyle("-fx-bar-fill: rgb(" + rgb + ");");
}
colors.put(series.getName(), rgb);
}
for (Node n : chart.getChildrenUnmodifiable())
{
if (n instanceof Legend)
{
for (LegendItem items : ((Legend)n).getItems())
{
String rgb = colors.get(items.getText());
items.getSymbol().setStyle("-fx-bar-fill: rgb(" + rgb + ");");
}
}
}
}