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JavaFX: Make Chips Editable in JFXChipView

I want to ask if it is possible to make a chip in JFXChipView editable once it has been set.

You can create your own JFXChip and implement a behavior to enable editing. First, you need to have an editable label. I looked up online and I found this post: JavaFX custom control - editable label. Then, you can extend JFXChip to use that EditableLabel:
import com.jfoenix.controls.JFXButton;
import com.jfoenix.controls.JFXChip;
import com.jfoenix.controls.JFXChipView;
import com.jfoenix.svg.SVGGlyph;
import javafx.beans.binding.Bindings;
import javafx.beans.property.Property;
import javafx.scene.layout.HBox;
public class EditableChip<T> extends JFXChip<Property<T>> {
protected final HBox root;
public EditableChip(JFXChipView<Property<T>> view, Property<T> item) {
super(view, item);
JFXButton closeButton = new JFXButton(null, new SVGGlyph());
closeButton.getStyleClass().add("close-button");
closeButton.setOnAction(event -> {
view.getChips().remove(item);
event.consume();
});
// Create the label with an initial value from the item
String initialValue = view.getConverter().toString(item);
EditableLabel label = new EditableLabel(initialValue);
label.setMaxWidth(100);
// Bind the item to the text in the label
item.bind(Bindings.createObjectBinding(() -> view.getConverter().fromString(label.getText()).getValue(), label.textProperty()));
root = new HBox(label, closeButton);
getChildren().setAll(root);
}
}
Note: I am using Property<T> instead of using the desired class T because JFXChipView stores the item the first time you add it. And in that case, you're going to get the values as you entered them the first time when calling JFXChipView#getChips().
Sample application:
import com.jfoenix.controls.JFXChipView;
import javafx.application.Application;
import javafx.beans.property.Property;
import javafx.beans.property.SimpleStringProperty;
import javafx.scene.Scene;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.StringConverter;
public class EditableChipViewApp extends Application {
#Override
public void start(Stage primaryStage) {
JFXChipView<Property<String>> chipView = new JFXChipView<>();
chipView.setChipFactory(EditableChip::new);
chipView.setConverter(new StringConverter<Property<String>>() {
#Override
public String toString(Property<String> object) {
return object == null ? null : object.getValue();
}
#Override
public Property<String> fromString(String string) {
return new SimpleStringProperty(string);
}
});
VBox container = new VBox(chipView);
Scene scene = new Scene(container, 800, 600);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
Result:
This is how you get the actual values of the chips:
List<String> chipsValues = chipView.getChips().stream().map(Property::getValue).collect(Collectors.toList());

How to increase the number of possible selections within a ToggleGroup (e.g. RadioButtons)?

I am somewhat new to programming and new to OOP (2nd Java project over all right now) and would love any hints or help.
I am currently working on a character creation program for my very own pen&paper game. I am using JavaFX (without FXML and thus without SceneBuilder) for the GUI part. I am working with Eclipse Neon on JDK1.8.0_131.
Here is my issue:
tl;dr: How to increase the number of possible selections within a ToggleGroup?
I am about to create a list of options for the user to choose from. The list consist of about 30 different advantages he or she can choose to improve their character. The allowed maximum of chosen options depends on the character and varies around 5. I already implemented an array of pairs (I know about HashMaps), where each entry is a pair consisting of the advantage's name and an integer representing its costs (they vary in their values, so in their costs).
The list itself should now be implemented via
ScrollPane scrollAdv = new ScrollPane();
VBox vBoxAdv = new VBox();
scrollAdv.setContent(vBoxAdv);
Pair<String, Integer>[] listAdv = info.getAdvantages();
for (int i = 0; i < listAdv.length; i++) {
String name = listAdv[i].getKey(); // delivers the 1st entry of a pair
int costs = listAdv[i].getValue(); // delivers the 2nd entry of a pair
ToggleButton toggleButton = new ToggleButton();
toggleButton.setUserData(name);
toggleButton.setText(name + " (" + costs + ")");
vBoxAdv.getChildren().add(toggleButton);
}
Note that I don't care too much about ToggleButtons and they could easily be replaced with RadioButtons. Both work the same way, if I understood the documentation correctly. They both use ToggleGroup to make sure, only one option is selected.
So while you probably guessed so by now, what I want to do is give the user the possibility to chose more than one option at once. I do not want to make it so the user has to chose one option after the other, while resetting the list in between.
Thanks for reading and thanks in advance for any help or hints.
edit: I could always just add a counter which refreshes whenever one option is selected or deselected and blocks any selection if it's < 1, but I thought that there should be a better solution, e.g. increase the built-in limit of 1 which ToggleGroup seems to be using.

One way would be to disable the remaining toggles when the limit is reached. Here's a ToggleSet class that does that:
import java.util.ArrayList;
import java.util.List;
import javafx.beans.Observable;
import javafx.beans.binding.Bindings;
import javafx.beans.binding.IntegerBinding;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.collections.transformation.FilteredList;
import javafx.scene.Node ;
import javafx.scene.control.Toggle;
public class ToggleSet<T extends Node & Toggle> {
private final ObservableList<T> toggles = FXCollections.observableArrayList(t -> new Observable[] {t.selectedProperty()});
private final FilteredList<T> selectedToggles = toggles.filtered(t -> ((Toggle)t).isSelected());
private final IntegerProperty maximumSelectable = new SimpleIntegerProperty(0);
private final IntegerBinding numSelected = Bindings.size(selectedToggles);
public ToggleSet(int maximumSelectable) {
this.maximumSelectable.addListener((obs, oldMax, newMax) -> {
if (newMax.intValue() < numSelected.get()) {
List<Toggle> togglesToClear = new ArrayList<>(selectedToggles.subList(0, numSelected.get() - newMax.intValue()));
togglesToClear.forEach(t -> t.setSelected(false));
}
});
setMaximumSelectable(maximumSelectable);
}
public ToggleSet() {
this(0);
}
public ObservableList<T> getSelectedToggles() {
return FXCollections.unmodifiableObservableList(selectedToggles) ;
}
public IntegerProperty maximumSelectableProperty() {
return maximumSelectable ;
}
public final int getMaximumSelectable() {
return maximumSelectableProperty().get();
}
public final void setMaximumSelectable(int maximumSelectable) {
maximumSelectableProperty().set(maximumSelectable);
}
public void addToggle(T toggle) {
if (numSelected.get() >= getMaximumSelectable()) {
toggle.setSelected(false);
}
toggles.add(toggle);
toggle.disableProperty().bind(toggle.selectedProperty().not().and(numSelected.greaterThanOrEqualTo(maximumSelectable)));
}
public void removeToggle(T toggle) {
toggles.remove(toggle);
toggle.disableProperty().unbind();
}
}
Here's an example testing it:
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.CheckBox;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;
import javafx.scene.control.Spinner;
import javafx.scene.control.ToggleButton;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class ToggleSetTest extends Application {
#Override
public void start(Stage primaryStage) {
ToggleSet<ToggleButton> toggleSet = new ToggleSet<>(5);
GridPane grid = new GridPane() ;
Spinner<Integer> maxSelectedSpinner = new Spinner<>(0, 20, 5);
maxSelectedSpinner.getValueFactory().valueProperty().bindBidirectional(toggleSet.maximumSelectableProperty().asObject());
grid.add(new HBox(2, new Label("Maximum selected"), maxSelectedSpinner), 0, 0, 2, 1);
grid.addRow(1, new Label("Selection"), new Label("Include in set"));
for (int i = 1; i <= 20 ; i++) {
RadioButton button = new RadioButton("Button "+i);
CheckBox checkBox = new CheckBox();
checkBox.selectedProperty().addListener((obs, wasChecked, isNowChecked) -> {
if (isNowChecked) {
toggleSet.addToggle(button);
} else {
toggleSet.removeToggle(button);
}
});
checkBox.setSelected(true);
grid.addRow(i + 1, button, checkBox);
}
grid.setPadding(new Insets(10));
grid.setHgap(5);
grid.setVgap(2);
Scene scene = new Scene(grid);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
If you want the same behavior as the ToggleGroup, where the previous selection becomes unselected, it's a little trickier, but the following should work:
import java.util.ArrayList;
import java.util.List;
import javafx.beans.Observable;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.Property;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.beans.value.ChangeListener;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Node ;
import javafx.scene.control.Toggle;
public class ToggleSet<T extends Node & Toggle> {
private final ObservableList<T> toggles = FXCollections.observableArrayList(t -> new Observable[] {t.selectedProperty()});
private final ObservableList<T> selectedToggles = FXCollections.observableArrayList();
private final IntegerProperty maximumSelectable = new SimpleIntegerProperty(0);
private final ChangeListener<Boolean> toggleListener = (obs, wasSelected, isNowSelected) -> {
#SuppressWarnings("unchecked")
T toggle = (T) ((Property<?>)obs).getBean();
if (isNowSelected) {
selectedToggles.add(toggle);
ensureWithinMax();
} else {
selectedToggles.remove(toggle);
}
};
public ToggleSet(int maximumSelectable) {
this.maximumSelectable.addListener((obs, oldMax, newMax) -> ensureWithinMax());
setMaximumSelectable(maximumSelectable);
}
private void ensureWithinMax() {
if (this.maximumSelectable.get() < selectedToggles.size()) {
List<Toggle> togglesToClear = new ArrayList<>(selectedToggles.subList(0, selectedToggles.size() - this.maximumSelectable.get()));
togglesToClear.forEach(t -> t.setSelected(false));
}
}
public ToggleSet() {
this(0);
}
public ObservableList<T> getSelectedToggles() {
return FXCollections.unmodifiableObservableList(selectedToggles) ;
}
public IntegerProperty maximumSelectableProperty() {
return maximumSelectable ;
}
public final int getMaximumSelectable() {
return maximumSelectableProperty().get();
}
public final void setMaximumSelectable(int maximumSelectable) {
maximumSelectableProperty().set(maximumSelectable);
}
public void addToggle(T toggle) {
if (toggle.isSelected()) {
selectedToggles.add(toggle);
ensureWithinMax();
}
toggle.selectedProperty().addListener(toggleListener);
toggles.add(toggle);
}
public void removeToggle(T toggle) {
toggle.selectedProperty().removeListener(toggleListener);
toggles.remove(toggle);
}
}
(Use the same test code.)

JavaFX TreeView of multiple object types? (and more)

I currently have the following object data structure:
Item
String name
ArrayList of information
Character
String name
Collection of Item
Account
String name
Collection of Character (up to 8 max)
I want to make a TreeView that looks like the following:
Root(invisible)
======Jake(Account)
============JakesChar(Character)
==================Amazing Sword(Item)
==================Broken Bow(Item)
==================Junk Metal(Item)
======Mark(Account)
============myChar(Character)
==================Godly Axe(Item)
======FreshAcc(Account)
======MarksAltAcc(Account)
============IllLvlThisIPromise(Character)
======Jeffrey(Account)
============Jeff(Character)
==================Super Gun(Item)
==================Better Super Gun(Item)
==================Super Gun Scope(Item)
I made all those names up and such, obviously the real implementation would be a lot more complex. How can this be done? The TreeItem requires each TreeItem to be the same type as its' parent.
The ONLY solution I have is to do the following:
public class ObjectPointer
{
Object pointer;
String name;
}
My TreeView would be of type ObjectPointer and on each row I would cast the ObjectPointer to Account, Character, or Item. This is AWFUL but I think it would work.
Sub Questions:
How do I get TreeItem(s) to detect setOnMouseHover events?
How do I get TreeItem(s) to not use the toString method of their type and instead a custom way of displaying the String property that they need?
How do I get the TreeItem(s) to display colored text in the GUI instead of plain text?
Thank you!

If you look at your model and think generically, all the classes have a degree of similarity, which you could factor out into a superclass:
package model;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
public abstract class GameObject<T extends GameObject<?>> {
public GameObject(String name) {
setName(name);
}
private final StringProperty name = new SimpleStringProperty();
public final StringProperty nameProperty() {
return this.name;
}
public final String getName() {
return this.nameProperty().get();
}
public final void setName(final String name) {
this.nameProperty().set(name);
}
private final ObservableList<T> items = FXCollections.observableArrayList();
public ObservableList<T> getItems() {
return items ;
}
public abstract void createAndAddChild(String name);
}
The type parameter T here represents the type of "child" objects. So your Account class (whose child type is GameCharacter - don't name classes the same as anything in java.lang, btw...) looks like
package model;
public class Account extends GameObject<GameCharacter> {
public Account(String name) {
super(name);
}
#Override
public void createAndAddChild(String name) {
getItems().add(new GameCharacter(name));
}
}
and similarly all the way down the hierarchy. I'd define an Information class (even though it just has a name) to make everything fit the structure, so:
package model;
public class Item extends GameObject<Information> {
public Item(String name) {
super(name);
}
#Override
public void createAndAddChild(String name) {
getItems().add(new Information(name));
}
}
and, since Information has no children, its child list is just an empty list:
package model;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
public class Information extends GameObject<GameObject<?>> {
public Information(String name) {
super(name);
}
#Override
public ObservableList<GameObject<?>> getItems() {
return FXCollections.emptyObservableList();
}
#Override
public void createAndAddChild(String name) {
throw new IllegalStateException("Information has no child items");
}
}
Now every item in your tree is a GameObject<?>, so you can basically build a TreeView<GameObject<?>>. The tricky part is that your tree items need to reflect the structure already built in the model. Since you have observable lists there, you can do this with listeners on the lists.
You can use a cell factory on the tree to customize the appearance of the cells displaying the TreeItems. If you want a different appearance for each type of item, I'd recommend defining the styles in an external CSS class, and setting a CSS PseudoClass on the cell corresponding to the type of item. If you use some naming convention (I have that the pseudo-class name is the lower case version of the class name), it can be quite slick to do that. Here's a fairly simple example:
package ui;
import static java.util.stream.Collectors.toList;
import java.util.Arrays;
import java.util.List;
import javafx.collections.ListChangeListener.Change;
import javafx.collections.ObservableList;
import javafx.css.PseudoClass;
import javafx.scene.control.TreeCell;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import model.Account;
import model.GameCharacter;
import model.GameObject;
import model.Information;
import model.Item;
public class Tree {
private final TreeView<GameObject<?>> treeView ;
private final List<Class<? extends GameObject<?>>> itemTypes = Arrays.asList(
Account.class, GameCharacter.class, Item.class, Information.class
);
public Tree(ObservableList<Account> accounts) {
treeView = new TreeView<>();
GameObject<?> root = new GameObject<Account>("") {
#Override
public ObservableList<Account> getItems() {
return accounts ;
}
#Override
public void createAndAddChild(String name) {
getItems().add(new Account(name));
}
};
TreeItem<GameObject<?>> treeRoot = createItem(root);
treeView.setRoot(treeRoot);
treeView.setShowRoot(false);
treeView.setCellFactory(tv -> {
TreeCell<GameObject<?>> cell = new TreeCell<GameObject<?>>() {
#Override
protected void updateItem(GameObject<?> item, boolean empty) {
super.updateItem(item, empty);
textProperty().unbind();
if (empty) {
setText(null);
itemTypes.stream().map(Tree.this::asPseudoClass)
.forEach(pc -> pseudoClassStateChanged(pc, false));
} else {
textProperty().bind(item.nameProperty());
PseudoClass itemPC = asPseudoClass(item.getClass());
itemTypes.stream().map(Tree.this::asPseudoClass)
.forEach(pc -> pseudoClassStateChanged(pc, itemPC.equals(pc)));
}
}
};
cell.hoverProperty().addListener((obs, wasHovered, isNowHovered) -> {
if (isNowHovered && (! cell.isEmpty())) {
System.out.println("Mouse hover on "+cell.getItem().getName());
}
});
return cell ;
}
}
public TreeView<GameObject<?>> getTreeView() {
return treeView ;
}
private TreeItem<GameObject<?>> createItem(GameObject<?> object) {
// create tree item with children from game object's list:
TreeItem<GameObject<?>> item = new TreeItem<>(object);
item.setExpanded(true);
item.getChildren().addAll(object.getItems().stream().map(this::createItem).collect(toList()));
// update tree item's children list if game object's list changes:
object.getItems().addListener((Change<? extends GameObject<?>> c) -> {
while (c.next()) {
if (c.wasAdded()) {
item.getChildren().addAll(c.getAddedSubList().stream().map(this::createItem).collect(toList()));
}
if (c.wasRemoved()) {
item.getChildren().removeIf(treeItem -> c.getRemoved().contains(treeItem.getValue()));
}
}
});
return item ;
}
private PseudoClass asPseudoClass(Class<?> clz) {
return PseudoClass.getPseudoClass(clz.getSimpleName().toLowerCase());
}
}
Quick test, which works, but note you probably need to test more of the functionality:
package application;
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
import model.Account;
import model.GameCharacter;
import model.GameObject;
import model.Information;
import model.Item;
import ui.Tree;
public class Main extends Application {
#Override
public void start(Stage primaryStage) throws Exception {
Tree tree = new Tree(createAccounts());
TreeView<GameObject<?>> treeView = tree.getTreeView();
TextField addField = new TextField();
Button addButton = new Button("Add");
EventHandler<ActionEvent> addHandler = e -> {
TreeItem<GameObject<?>> selected = treeView
.getSelectionModel()
.getSelectedItem();
if (selected != null) {
selected.getValue().createAndAddChild(addField.getText());
addField.clear();
}
};
addField.setOnAction(addHandler);
addButton.setOnAction(addHandler);
addButton.disableProperty().bind(Bindings.createBooleanBinding(() -> {
TreeItem<GameObject<?>> selected = treeView.getSelectionModel().getSelectedItem() ;
return selected == null || selected.getValue() instanceof Information ;
}, treeView.getSelectionModel().selectedItemProperty()));
Button deleteButton = new Button("Delete");
deleteButton.setOnAction(e -> {
TreeItem<GameObject<?>> selected = treeView.getSelectionModel().getSelectedItem() ;
TreeItem<GameObject<?>> parent = selected.getParent() ;
parent.getValue().getItems().remove(selected.getValue());
});
deleteButton.disableProperty().bind(treeView.getSelectionModel().selectedItemProperty().isNull());
HBox controls = new HBox(5, addField, addButton, deleteButton);
controls.setPadding(new Insets(5));
controls.setAlignment(Pos.CENTER);
BorderPane root = new BorderPane(treeView);
root.setBottom(controls);
Scene scene = new Scene(root, 600, 600);
scene.getStylesheets().add(getClass().getResource("/ui/style/style.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
private ObservableList<Account> createAccounts() {
Account jake = new Account("Jake");
Account mark = new Account("Mark");
Account freshAcc = new Account("Fresh Account");
Account marksAltAcc = new Account("Mark's alternative account");
Account jeffrey = new Account("Jeffrey");
GameCharacter jakesChar = new GameCharacter("Jakes character");
Item amazingSword = new Item("Amazing Sword");
Item brokenBow = new Item("Broken Bow");
Item junkMetal = new Item("Junk Metal");
GameCharacter myChar = new GameCharacter("Me");
Item godlyAxe = new Item("Godly Axe");
GameCharacter level = new GameCharacter("I'll level this I promise");
GameCharacter jeff = new GameCharacter("Jeff");
Item superGun = new Item("Super Gun");
Item superGunScope = new Item("Super Gun Scope");
jake.getItems().add(jakesChar);
mark.getItems().add(myChar);
marksAltAcc.getItems().add(level);
jeffrey.getItems().add(jeff);
jakesChar.getItems().addAll(amazingSword, brokenBow, junkMetal);
myChar.getItems().add(godlyAxe);
jeff.getItems().addAll(superGun, superGunScope);
return FXCollections.observableArrayList(jake, mark, freshAcc, marksAltAcc, jeffrey);
}
}
and the CSS as an example:
.tree-cell, .tree-cell:hover:empty {
-fx-background-color: -fx-background ;
-fx-background: -fx-control-inner-background ;
}
.tree-cell:hover {
-fx-background-color: crimson, -fx-background ;
-fx-background-insets: 0, 1;
}
.tree-cell:account {
-fx-background: lightsalmon ;
}
.tree-cell:gamecharacter {
-fx-background: bisque ;
}
.tree-cell:item {
-fx-background: antiquewhite ;
}
.tree-cell:selected {
-fx-background: crimson ;
}

PieChart (JavaFx) didn't display my Label on Event - JavaFx

I try to create a label on click for my PieChart, but unfortunately my label is never visible.
I found a similar topic on StackOverFlow : Label not showing on mouse event JavaFx
But my application is not as simple. I can't add my Label to the list of children because of my architecture.
(You can found a diagram here : http://i.stack.imgur.com/ZFJaR.png )
Here my code :
PieChartNode.java
package nodeStatsVision.chartFactory;
import java.util.ArrayList;
import javafx.application.Platform;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.scene.Node;
import javafx.scene.chart.PieChart;
import javafx.scene.control.Label;
import javafx.scene.input.MouseEvent;
import javafx.scene.paint.Color;
import nodeStatsVision.beans.ListRepere;
import nodeStatsVision.beans.OptionsChart;
import nodeStatsVision.beans.ValueStat;
/**
*
* #author Zombkey.
*/
public class PieChartNode implements ChartNode {
private ListRepere categories;
private ArrayList<ValueStat> values;
private ObservableList<PieChart.Data> pieChartData;
private Node node;
public PieChartNode(ListRepere categories, ArrayList<ValueStat> values){
this.categories = categories;
this.values = values;
pieChartData = FXCollections.observableArrayList();
node = new PieChart(pieChartData);
Platform.runLater(new Runnable() {
#Override
public void run() {
formatData();
}
});
}
private void formatData() {
final Label caption = new Label("");
caption.setTextFill(Color.DARKORANGE);
caption.setStyle("-fx-font: 24 arial;");
for(ValueStat v : values){
PieChart.Data dataTemp = new PieChart.Data(v.getCategorie().getStringName(),v.getDoubleValue());
pieChartData.add(dataTemp);
dataTemp.getNode().addEventHandler(MouseEvent.MOUSE_CLICKED,
new EventHandler<MouseEvent>() {
#Override public void handle(MouseEvent e) {
System.out.println("event : "+v.getCategorie().getStringName()+" : "+v.getDoubleValue());
caption.setTranslateX(e.getSceneX());
caption.setTranslateY(e.getSceneY());
caption.setText(String.valueOf(dataTemp.getPieValue()));
caption.setVisible(true);
System.out.println("label "+caption);
}
});
}
}
#Override
public Node getNodeGraph() {
return node;
}
#Override
public void setOptions(OptionsChart optionsChart) {
//To implemente
}
}
Have you a idea about, how add my Label to the scene ?
Thanks !
(Other question, Why the Node of PieChart.Data is on ReadOnly ?)
Zombkey.
PS : Sorry about my english, I'm a French student, I'm still learning :)
Ps 2 : First time on StackOverflow, if I did mistake, tell me it !

Ok ! I found a solution for my case !
Semantically my Label is only for my PieChart. That's why I don't want had it to my SceneGraph.
My ChartFactory return a Node, then display it. So my node have to contain the PieChart AND the Label.
I create a Group with a StackPane. In the StackPane I add my PieChart and my Label. Then my factory return the Group as a Node.
Drop the code !
package nodeStatsVision.chartFactory;
import java.util.ArrayList;
import javafx.application.Platform;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.chart.PieChart;
import javafx.scene.control.Label;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import nodeStatsVision.beans.ListRepere;
import nodeStatsVision.beans.OptionsChart;
import nodeStatsVision.beans.ValueStat;
/**
*
* #author Zombkey.
*/
public class PieChartNode implements ChartNode {
private ListRepere categories;
private ArrayList<ValueStat> values;
private ObservableList<PieChart.Data> pieChartData;
private Group group;
private Node node;
private final Label caption;
public PieChartNode(ListRepere categories, ArrayList<ValueStat> values){
this.categories = categories;
this.values = values;
group = new Group();
StackPane pane = new StackPane();
group.getChildren().add(pane);
pieChartData = FXCollections.observableArrayList();
node = new PieChart(pieChartData);
pane.getChildren().add(node);
caption = new Label("");
caption.setVisible(false);
caption.getStyleClass().addAll("chart-line-symbol", "chart-series-line");
caption.setStyle("-fx-font-size: 12; -fx-font-weight: bold;");
caption.setMinSize(Label.USE_PREF_SIZE, Label.USE_PREF_SIZE);
pane.getChildren().add(caption);
Platform.runLater(new Runnable() {
#Override
public void run() {
formatData();
}
});
}
private void formatData() {
for(ValueStat v : values){
PieChart.Data dataTemp = new PieChart.Data(v.getCategorie().getStringName(),v.getDoubleValue());
pieChartData.add(dataTemp);
dataTemp.getNode().addEventHandler(MouseEvent.MOUSE_ENTERED,
new EventHandler<MouseEvent>() {
#Override public void handle(MouseEvent e) {
caption.setTranslateX(e.getX());
caption.setTranslateY(e.getY());
caption.setText(String.valueOf(dataTemp.getPieValue()));
caption.setVisible(true);
}
});
dataTemp.getNode().addEventHandler(MouseEvent.MOUSE_EXITED,
new EventHandler<MouseEvent>() {
#Override public void handle(MouseEvent e) {
caption.setVisible(false);
}
});
}
}
#Override
public Node getNodeGraph() {
return (Node)group;
}
#Override
public void setOptions(OptionsChart optionsChart) {
//To implemente
}
}
Thanks #eckig for your answers !

You create and style your Label named caption but never add it to the SceneGraph.
Somewhere it has to be added to a Parent element, otherwise it will not get displayed.
Your PieChart gets added to a parent element, otherwise it will not be displayed. The same way goes for all other JavaFX Nodes.
As to your second question, read the JavaDocs:
Readonly access to the node that represents the pie slice. You can use this to add mouse event listeners etc.

You could use Tooltip to display a value:
for (final PieChart.Data temp : pieChart.getData()) {
Tooltip tooltip = new Tooltip(String.valueOf(temp.getPieValue()));
Tooltip.install(temp.getNode(), tooltip);
}

PaginationSample Javafx cannot assign a value to final variable pagination

I'm trying to reproduce a Pagination Sample from oracle samples, but when I imported the project something strange happened that I can not build and run the project:
The complete code is:
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Node;
import javafx.scene.control.*;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.util.Callback;
public class PaginationSample extends Application {
private final Pagination pagination;
private Image[] images = new Image[7];
private void init(Stage primaryStage) {
Group root = new Group();
primaryStage.setScene(new Scene(root));
VBox outerBox = new VBox();
outerBox.setAlignment(Pos.CENTER);
//Images for our pages
for (int i = 0; i < 7; i++) {
images[i] = new Image(PaginationSample.class.getResource("animal" + (i + 1) + ".jpg").toExternalForm(), false);
}
pagination = PaginationBuilder.create().pageCount(7).pageFactory(new Callback<Integer, Node>() {
#Override public Node call(Integer pageIndex) {
return createAnimalPage(pageIndex);
}
}).build();
//Style can be numeric page indicators or bullet indicators
Button styleButton = ButtonBuilder.create().text("Toggle pagination style").onAction(new EventHandler<ActionEvent>() {
public void handle(ActionEvent me) {
if (!pagination.getStyleClass().contains(Pagination.STYLE_CLASS_BULLET)) {
pagination.getStyleClass().add(Pagination.STYLE_CLASS_BULLET);
} else {
pagination.getStyleClass().remove(Pagination.STYLE_CLASS_BULLET);
}
}
}).build();
outerBox.getChildren().addAll(pagination, styleButton);
root.getChildren().add(outerBox);
}
//Creates the page content
private VBox createAnimalPage(int pageIndex) {
VBox box = new VBox();
ImageView iv = new ImageView(images[pageIndex]);
box.setAlignment(Pos.CENTER);
Label desc = new Label("PAGE " + (pageIndex + 1));
box.getChildren().addAll(iv, desc);
return box;
}
#Override public void start(Stage primaryStage) throws Exception {
init(primaryStage);
primaryStage.show();
}
public static void main(String[] args) { launch(args); }
}
But netbeans show me the error "cannot assign a value to final variable pagination" for the following line:
pagination = PaginationBuilder.create().pageCount(7).pageFactory(new Callback<Integer, Node>() {
Someone can explain me what is going wrong??

A final field can be initialized only once. So the best place to initialize it is when its declared
private final Pagination pagination = new Pagination(...);
or it can be done in the constructor, since the constructor is assured to be called once per instance
private final Pagination pagination;
public PaginationSample() {
pagination = new Pagination(...);
}
final field cannot be initialized in a method because a method can be called multiple times once an instance of that class gets created