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java fx remove stackPane

I need help creating a delete button on a stack pane in JavaFX.
It should remove the chosen stack pane from the group.
RinStackPane is extended javafx StackPane, gp is java fx Group.
Thank you in advance!
Here is my code:
private void setOnCreateMathOperation(Button createMathOperationBtn) {
createMathOperationBtn.setOnAction(event -> {
var mathOperation = createMathOperation();
RinStackPane stack1 = new RinStackPane();
stack1.setNodeType(NodesTypes.MathOperation);
stack1.setUnderlyingNode(mathOperation);
stack1.setName(mathOperation.getName());
stack1.getChildren().add(mathOperation);
TextField newtf1 = new TextField();
GridPane grid = new GridPane();
grid.addRow(1, newtf1);
stack1.getChildren().add(grid);
makeDraggable(stack1);
addToRectCollection(stack1);
gp.getChildren().add(stack1);
});
}

I am not sure if you want to keep the delete button inside or outside the StackPane.
Anyway you can easily bind an ObservableList to the Group's children. When an elemente will be deleted from the list, automatically this event will be reflected on Group's children:
//Create observable list of Node (you can constrain to RinStackPane if you prefer):
ObservableList<Node> list = FXCollections.observableArrayList();
//bind lists to gp's children:
Bindings.bindContentBidirectional(list, gp.getChildren());
Your code:
private void setOnCreateMathOperation(Button createMathOperationBtn) {
createMathOperationBtn.setOnAction(event -> {
RinStackPane stack1 = new RinStackPane();
//...
//setup the stack
//...
//Add the delete button to the stack:
Button deleteButton = new Button("Delete me!");
deleteButton.setOnMouseClicked(event -> {
list.remove(stack1); //<--- remove action
});
stack1.getChildren().add(deleteButton);
//add to the list instead of gp's children
list.add(stack1);
});
}
Note how the stack is not added nor removed to/from the gp's children, instead the list is used.
If you want the deleteButton outside the stack the code is the same, just be sure that both list and stack1 are somehow passed to the button's click handler.
Hope this helps.

How to hide TabPane content on Tab clicked in JavaFX

Here is a code:
package tabpane;
import javafx.application.*;
import javafx.geometry.*;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.*;
public class HideShowTabContentOnClicked extends Application {
public static void main(String[] args) {
launch(args);
}
private BorderPane createContent() {
BorderPane borderPane = new BorderPane();
TabPane tabPane = new TabPane();
tabPane.setSide(Side.LEFT);
StackPane stackPane = new StackPane();
stackPane.setStyle("-fx-background-color: lightblue");
stackPane.setMinWidth(200);
Tab firstTab = new Tab("First");
firstTab.setClosable(false);
firstTab.setContent(stackPane);
firstTab.selectedProperty().addListener((observable, oldValue, newValue) -> {
if (!newValue) {
firstTab.setContent(null);
} else {
firstTab.setContent(stackPane);
}
});
Tab secondTab = new Tab("Second");
StackPane stackPane2 = new StackPane();
stackPane2.setStyle("-fx-background-color: yellow");
secondTab.setContent(stackPane2);
secondTab.setClosable(false);
secondTab.selectedProperty().addListener((observable, oldValue, newValue) -> {
if (!newValue) {
secondTab.setContent(null);
} else {
secondTab.setContent(stackPane2);
}
});
StackPane center = new StackPane();
center.setStyle("-fx-background-color: cyan");
borderPane.setCenter(center);
tabPane.getTabs().addAll(firstTab, secondTab);
borderPane.setLeft(tabPane);
return borderPane;
}
#Override
public void start(Stage stage) throws Exception {
stage.setScene(new Scene(createContent()));
stage.setMaximized(true);
stage.show();
}
}
Here I tried to solve a problem by using selectedProperty() by setting content to null, but it doesn't working, I want to make Tab like toggle button so that when I click on it showed and hide TabPanes content.
Before
And when clicked
As an example I want to implement TabPane like Intellij IDEA Tool Buttons (like "Project", "Structure" Tool Buttons etc).

If you are going to keep your content into StackPane, you can bind stackPane.visibleProperty() with toggleButton.selectedProperty():
stackPane.visibleProperty()
.bind(Bindings.when(toggleButton.selectedProperty())
.then(false)
.otherwise(true)
);
in this exampl: toggleButton.isSelected() --> !stackPane.isVisible() and !toggleButton.isSelected() --> stackPane.isVisible(),
or listen ToggleButton's events:
// toggleButton.setOnAction(e ->{ //new .setOnAction() -> Override previous
toggleButton.addEventHandler(ActionEvent.ACTION, e ->{ //can add any quantity for your needs
if(toggleButton.isSelected())
stackPane.setVisible(false);
else stackPane.setVisible(true);
});
But the problem is instead of toggle button I want to use Tab, so that it behaves like toggle button. i.e. when click "First Tab" in my example code if content visible it should be invisible and vice versa. I mean only tabs should be shown
I found solution.Tab does not have click-handler... but
Tab tab = new Tab();
tab.setContent(stackPane);
Label lable = new Label("Label"); //create Label
tab.setGraphic(lable); //set Lable as Graphic to Tab
lable.setOnMouseClicked(event ->{ //setOnMouseClicked, for example
if(stackPane.isVisible()){
stackPane.setVisible(false);
}else{
stackPane.setVisible(true);
}
});
, you can use Label(for example) as Tab-text and add setOnMouseClicked()-handler to Label. You can use any Node with Handler/ActionListener -> It's up to you.
For example, you can use CheckBox to show/hide StackPane, and Tab text (you can combine FXML and Java-code to produce graphics):
Tab tab = new Tab("Tab2"); //Tab with Text
tab.setContent(stackPane);
CheckBox checkBox = new CheckBox(); //create CheckBox
tab.setGraphic(checkBox); //set CheckBox as Graphic to Tab
stackPane.visibleProperty()
.bind(Bindings.when(checkBox.selectedProperty())
.then(false)
.otherwise(true)
);
or
#FXML
private Tab tab;
// ...
tab.setGraphic(checkBox);
// ...

I have came up with this solution:
AtomicReference<Tab> currentTab = new AtomicReference<>(tabPane.getSelectionModel().getSelectedItem());
AtomicReference<Tab> lastTab = new AtomicReference<>(null);
tabPane.setOnMouseReleased(event -> {
// Check if current node is actually tab
Node n = event.getPickResult().getIntersectedNode();
while (n != null && !(n.getStyleClass().contains("headers-region"))) {
n = n.getParent();
}
if (n == null)
return;
lastTab.set(currentTab.get());
currentTab.set(tabPane.getSelectionModel().getSelectedItem());
if (currentTab.get() == lastTab.get()) {
// Hide
tabPane.setPrefSize(28, 28);
//tabPane.getSelectionModel().clearSelection(); // notify selection model
currentTab.set(null);
} else {
// Show
tabPane.setPrefSize(-1,-1);
currentTab.set(tabPane.getSelectionModel().getSelectedItem());
}
});
First of all, I have added mouse event to the tabPane. Inside this mouse event, check if node under cursor is actually Tab node. If it is, do some logic to identify what user is trying to do: hide or show. Hiding is a bit tricky, so I ended up with setting preferred size of TabPane to 28 px wide.
I have also tried to notify selection model with an empty newValue:
tabPane.getSelectionModel().clearSelection();
But this it is not working properly. Calling select(-1) should call clearSelection(), but behavior is different somehow.
When I select another tab after calling clearSelection(), selection model handler called with oldValue == null, that possibly does not update internal index and tab does not swithes to selected one.

JavaFX: Getting IDs of Dynamic created Button

I'm currently made an Form with JavaFX.
Always i press a Button, i call the "addAnswer()"-Method.
In that I create a RadioButton, a Label and a delete-Button, which i bundle in a HBox. All that HBoxes i pack in a vBox.
The Problem now is the delete-Button. I want to delte just THAT HBox in which the clicked Button is.
Here is my code:
public void addAnswer() {
this.rB = new RadioButton();
checkAnswer.getToggles().add(rB);
hBox = new HBox();
tF = new TextField();
delAnswer = new Button("Löschen");
delAnswer.setId(Integer.toString(counter));
hBox.getChildren().addAll(rB, tF, delAnswer);
hBox.setId(Integer.toString(counter));
delAnswer.setOnAction(e -> delAnswer(Integer.parseInt(hBox.getId())));
System.out.println(delAnswer.getId());
vBox.getChildren().addAll(hBox);
counter++;
}
public void delAnswer(int e){
vBox.getChildren().remove(delAnswer.getId());
}
i tried this one above but i realized, that all the delAnswers-Buttons have the same ID: the number of how often i pressed the add-Button.
Is there any solution where i can just select that one i pressed with that dynamic way? Cause i don't kow how often somebody will press or delete something.
Thanks

hbox is a field and this is why always the HBox last added is used. (hBox is evaluated, when lambda body is executed, not at the time of the lambda creation). This would be different, if you used a (effectively) final local variable:
final HBox hBoxLocal = hBox;
delAnswer.setOnAction(e -> delAnswer(Integer.parseInt(hBoxLocal.getId())));
However I'd like to present a different solution which would allow you to use the same EventHandler<ActionEvent> for all delete Buttons:
You can get the Node that triggered the event using getSource. From this Node you can get the parent, which is the HBox. You can remove this from the VBox using the remove(Object) method
delAnswer.setOnAction(e -> {
// get button
Node source = (Node) e.getSource();
// remove parent of button from VBox
vBox.getChildren().remove(source.getParent());
});

I think your problem is that you give the same event to all your button,Begin by creating a list that stores your buttons and then increments the value of the ID after affecting it to an item :
List<Button> buttons = new ArrayList<>();
/*
Create Button and call IDEvt method to create new event
for each button
*/
private void IDEvt(Button btn){
btn.setId(String.valueOf(IDRank));
btn.setOnMousePressed(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
System.out.println(btn.getId());
}
});
IDRank++;
}

JavaFX ComboBox Image

I am trying to create a ComboBox that will display a preview of selected Image, but the ComboBox displays the string value instead.
The only way appears to work is to create ComboBox of Node, but that causes once selected option disappear from the drop down menu, would appreciate if someone has any suggestions.
My code below:
String notOnLine = "file:Java1.png";
String onLine = "file:Java2.png";
ObservableList<String> options = FXCollections.observableArrayList();
options.addAll(notOnLine, onLine);
final ComboBox<String> comboBox = new ComboBox(options);
comboBox.setCellFactory(c -> new StatusListCell());
and the ListCell:
public class StatusListCell extends ListCell<String> {
protected void updateItem(String item, boolean empty){
super.updateItem(item, empty);
setGraphic(null);
setText(null);
if(item!=null){
ImageView imageView = new ImageView(new Image(item));
imageView.setFitWidth(40);
imageView.setFitHeight(40);
setGraphic(imageView);
setText("a");
}
}
}
I'd like the image to be displayed in the ComboBox itself once the list is closed. Right now it's just showing the URL (e.g. file:Java1.png).

You can specify the buttonCellProperty of the ComboBox:
comboBox.setButtonCell(new StatusListCell());
The button cell is used to render what is shown in the ComboBox
'button' area.

JavaFX MenuItem does not react on MouseEvent.CLICKED

I am writting a little desktop application with a TreeView according to the Oracle-Example from here: https://docs.oracle.com/javafx/2/ui_controls/tree-view.htm.
From a MenuItem action of a ContextMenu, I would like to fire an event which shall create a new TreeItem below the item where I opened the ContextMenu from.
For MenuItem, it is possible to use the setOnAction(EventHandler<ActionEvent> event) method, but I only want to fire the action from a left mouse-click.
First, it is not possible to add an EventHandler to a MenuItem although it provides the method addEventHandler(EventType type, EventHandler<EventType> handler) with the event-type MouseEvent.ANY (or anything else). The handle-method of the event-handler is not called.
Second, i can use a workarround by adding a Label to a MenuItem by menuItem.setGraphic(label) and add an EventHandler to the label. This one works although MouseEvent.MOUSE_CLICKED is not called by an EventHandler's handle-method on a Label.
Is this "normal" behaviour? I understand that a label does not react on a click-event, but I do not understand why it is not possible to register a separate EventHandler or EventFilter on a MenuItem.

ContextMenu uses a MenuItemContainer, which is a
Container responsible for laying out a single row in the menu - in other
words, this contains and lays out a single MenuItem, regardless of it's
specific subtype.
Fur this purpose it seems to create new Nodes representing the MenuItem. So any EventHandlers added to the MenuItem will not be called.
To make it work as you intended, you can use a CustomMenuItem and add the according EventHandler to its content:
public class ContextMenuCell extends TreeCell<String> {
private ContextMenu menu;
public ContextMenuCell() {
Label lbl = new Label("Add item");
MenuItem menuItem = new CustomMenuItem(lbl);
lbl.setOnMouseClicked(evt -> {
if (evt.getButton() != MouseButton.PRIMARY) {
return;
}
TreeItem treeItem =
new TreeItem<String>("New item");
if (getTreeItem().isLeaf()) {
getTreeItem().getParent().getChildren().add(getIndex(), treeItem);
} else {
getTreeItem().getChildren().add(0, treeItem);
}
});
menu = new ContextMenu(menuItem);
}
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
setText(item);
setGraphic(getTreeItem().getGraphic());
setContextMenu(menu);
}
}
}

Menu and MenuItem are not Nodes, so they will not handle mouse clicks since they are not displayed on the screen. A workaround is to set a graphics object (Node) to the MenuItem and add the listener to this Node. Works also for other menus like CheckMenuItem etc.:
public class RunJavaFX extends Application {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage primaryStage) throws Exception {
//the label will be our graphics object (Node)
Label l = new Label("Your Menu Text");
l.setTextFill(Color.BLACK); //set black since default CSS Style sets it to background color of the Menu
//add either over addEventFilter or addEventHandler
l.addEventFilter(MouseEvent.MOUSE_PRESSED, ev -> {
if (ev.getButton() == MouseButton.SECONDARY) {
System.out.println("RightClick: " + ev.getSource() + System.nanoTime());
} else {
System.out.println("Not Right Click: " + ev.getSource() + System.nanoTime());
}
ev.consume(); //optional
});
//create the MenuItem with an empty text and set the label l as graphics object
MenuItem mI = new MenuItem("", l);
//create the dummy menu and MenuBar for the example
Menu m = new Menu("Menu");
m.getItems().add(mI);
MenuBar mB = new MenuBar(m);
//create the dummy scene for the example
Scene scene = new Scene(mB);
primaryStage.setScene(scene);
primaryStage.show();
}
}