Handling events from within a PopupWindow - java

I've made my own TimePicker that is supposed to work very much like DatePicker. I would like to know the best way to handle an event such as selecting a time and confirming it from the PopupWindow.
I could:
Make my TimePicker's popup node (a separate FXML and controller) define an interface and force the TimePicker parent to implement the methods to handle the selected date. (I'd MUCH like to avoid using interfaces in this manner. It seems like a terribly way to do things.)
Register some kind of custom EventHandler and listener to the popup window? Then, if I click OKAY after selecting a date from the PopupWindow, an event can be fired all the way up to the TimePicker.
Implement some kind of callback-like function. In android, for example, there were options for going to another screen solely to retrieve a result. I'm not sure if JavaFX has that kind of thing. The screens are quite separated from each other.

Just expose a ReadOnlyProperty representing the value. The user of your popup can then just observe the property.
Here's a proof of concept using a DatePicker:
import java.time.LocalDate;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyObjectProperty;
import javafx.beans.property.ReadOnlyObjectWrapper;
import javafx.geometry.Bounds;
import javafx.geometry.Insets;
import javafx.geometry.Point2D;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.DatePicker;
import javafx.scene.control.Label;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.stage.Popup;
import javafx.stage.PopupWindow;
import javafx.stage.Stage;
public class DatePickerPopupExample extends Application {
#Override
public void start(Stage primaryStage) {
Label dateLabel = new Label(LocalDate.now().toString());
Button changeButton = new Button("Change");
HBox root = new HBox(5, dateLabel, changeButton);
root.setAlignment(Pos.CENTER);
changeButton.setOnAction(event -> {
DatePickerPopup popup = new DatePickerPopup();
popup.valueProperty().addListener((obs, oldDate, newDate) -> {
dateLabel.setText(newDate.toString());
});
Bounds buttonBds = changeButton.getBoundsInLocal();
Point2D loc = changeButton.localToScreen(buttonBds.getMaxX(), buttonBds.getMinY());
popup.showPopup(primaryStage, loc.getX(), loc.getY());
});
Scene scene = new Scene(root, 250, 150);
primaryStage.setScene(scene);
primaryStage.show();
}
public class DatePickerPopup {
private final ReadOnlyObjectWrapper<LocalDate> value = new ReadOnlyObjectWrapper<>();
private final Popup popup ;
public ReadOnlyObjectProperty<LocalDate> valueProperty() {
return value.getReadOnlyProperty();
}
public final LocalDate getValue() {
return valueProperty().get();
}
public DatePickerPopup(LocalDate date) {
value.set(date);
DatePicker picker = new DatePicker(date);
Button okButton = new Button("OK");
okButton.setOnAction(event -> {
popup.hide();
value.set(picker.getValue());
});
Button cancelButton = new Button("Cancel");
cancelButton.setOnAction(event -> {
popup.hide();
});
BorderPane root = new BorderPane();
root.setCenter(picker);
HBox buttons = new HBox(5, okButton, cancelButton);
buttons.setPadding(new Insets(5));
buttons.setAlignment(Pos.CENTER);
root.setBottom(buttons);
popup = new Popup();
popup.getContent().add(root);
}
public DatePickerPopup() {
this(LocalDate.now());
}
public void showPopup(Stage owner, double x, double y) {
popup.show(owner, x, y);
}
}
public static void main(String[] args) {
launch(args);
}
}

Related

Let user define keyboard shortcut

To ease the use of my JavaFx application I want to allow the user to define a keyboard combination / shortcut to trigger the most important action of the application.
I know how to define a KeyCodeCombination in code and set it as Accelerator or use it in an KeyEvent listener but instead of hard-coding it, I would like to allow the user to define his own KeyCodeCombination by simply pressing it on his keyboard in a certain settings dialog.
Basically something along this pseudocode:
// how would I implement the next two lines
Dialog dialog = new KeyboardShortcutDefinitionDialog();
KeyCombination shortcut = dialog.recordKeyboardShortcut();
// I know how to do the rest from here
shortcutLabel.setText(shortcut.toString());
SettingsManager.storeShortcut(shortcut);
Application.setupShortcut(shortcut);
Here's a small example of listening for a KEY_PRESSED event and building a KeyCombination out of it.
import java.util.ArrayList;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.input.KeyCodeCombination;
import javafx.scene.input.KeyCombination;
import javafx.scene.input.KeyCombination.Modifier;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.StackPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;
public class Main extends Application {
#Override
public void start(Stage primaryStage) {
var label = new Label();
label.setFont(Font.font("Segoe UI", 15));
primaryStage.addEventHandler(KeyEvent.KEY_PRESSED, event -> {
if (!event.getCode().isModifierKey()) {
label.setText(createCombo(event).getDisplayText());
}
});
primaryStage.setScene(new Scene(new StackPane(label), 500, 300));
primaryStage.setResizable(false);
primaryStage.show();
}
private KeyCombination createCombo(KeyEvent event) {
var modifiers = new ArrayList<Modifier>();
if (event.isControlDown()) {
modifiers.add(KeyCombination.CONTROL_DOWN);
}
if (event.isMetaDown()) {
modifiers.add(KeyCombination.META_DOWN);
}
if (event.isAltDown()) {
modifiers.add(KeyCombination.ALT_DOWN);
}
if (event.isShiftDown()) {
modifiers.add(KeyCombination.SHIFT_DOWN);
}
return new KeyCodeCombination(event.getCode(), modifiers.toArray(Modifier[]::new));
}
}

JavaFx - Method Undefined

I have to create a program using JavaFX that creates a pane with a ball in it. There are four buttons that move the ball either left, right, up, or down. I don't understand why when I go to define each method (like .left() shown) the method call above remains an error that tells me it is undefined.
Main class:
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.BorderPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
public class MoveTheBall extends Application {
#Override
public void start(Stage primaryStage) {
StackPane pane = new StackPane();
Circle circle = new Circle(20);
circle.setStroke(Color.BLACK);
circle.setFill(Color.WHITE);
pane.getChildren().add(circle);
HBox hBox = new HBox();
hBox.setSpacing(10);
hBox.setAlignment(Pos.CENTER);
Button btLeft = new Button("Left");
Button btRight = new Button("Right");
Button btUp = new Button("Up");
Button btDown = new Button("Down");
hBox.getChildren().add(btLeft);
hBox.getChildren().add(btRight);
hBox.getChildren().add(btUp);
hBox.getChildren().add(btDown);
BorderPane borderPane = new BorderPane();
borderPane.setCenter(pane);
borderPane.setBottom(hBox);
BorderPane.setAlignment(hBox, Pos.CENTER);
Scene scene = new Scene(borderPane, 300, 200);
primaryStage.setTitle("Move The Ball");
primaryStage.setScene(scene);
primaryStage.show();
}
}
Buttons class:
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.BorderPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
public class ControlBall extends Application {
private MoveTheBall moveTheBall = new MoveTheBall();
#Override
public void start(Stage primaryStage) {
HBox hBox = new HBox();
hBox.setSpacing(5);
hBox.setAlignment(Pos.CENTER);
Button btLeft = new Button("Left");
Button btRight = new Button("Right");
Button btUp = new Button("Up");
Button btDown = new Button("Down");
hBox.getChildren().add(btLeft);
hBox.getChildren().add(btRight);
hBox.getChildren().add(btUp);
hBox.getChildren().add(btDown);
btLeft.setOnAction(new LeftHandler());
btRight.setOnAction(new RightHandler());
btUp.setOnAction(new UpHandler());
btDown.setOnAction(new DownHandler());
BorderPane borderPane = new BorderPane();
borderPane.setCenter(moveTheBall);
borderPane.setBottom(hBox);
BorderPane.setAlignment(hBox, Pos.CENTER);
Scene scene = new Scene(borderPane, 200, 150);
primaryStage.setTitle("Move The Ball");
primaryStage.setScene(scene);
primaryStage.show();
}
class LeftHandler implements EventHandler<ActionEvent> {
#Override
public void handle(ActionEvent e) {
moveTheBall.left(); // error because no class yet
}
}
class RightHandler implements EventHandler<ActionEvent> {
#Override
public void handle(ActionEvent e) {
moveTheBall.right(); // error because no class yet
}
}
class UpHandler implements EventHandler<ActionEvent> {
#Override
public void handle(ActionEvent e) {
moveTheBall.up(); // error because no class yet
}
}
class DownHandler implements EventHandler<ActionEvent> {
#Override
public void handle(ActionEvent e) {
moveTheBall.down(); // error because no class yet
}
}
}
class moveTheBall extends StackPane {
private Circle ball = new Circle(20);
public moveTheBall() {
getChildren().add(ball);
ball.setStroke(Color.BLACK);
ball.setFill(Color.WHITE);
}
public void left() {
ball.setCenterX(-2.0);
ball.setCenterY(-2.0);
}
}
The line borderPane.setCenter(moveTheBall); is giving me problems as well. "The method setCenter(Node) in the type BorderPane is not applicable for the arguments (MoveTheBall)"
I'm pretty new to JavaFX, but I'm gonna do the best I can here.
I would suggest instead of doing totally separate classes for controlling the ball, moving the ball, and handling each button, look into using lambda expressions to simplify the code and reduce your room for error. For example, you can set what the btRight button does by writing a line like this:
btRight.setOnAction(e -> {
//if the ball is inside the right limit
//Move the ball to the right
});
You can write these expressions directly into your start() method, and avoid defining inner classes, as well as a separate class for the control.
As far as why you are getting an error, my best guess (as i said, I'm new to this) is that moveTheBall() is a constructor for the MoveTheBall class, but it is being called as a method.
Hope this helps.

JavaFX binding between TextField and a property

If you create a binding between a JavaFX TextField and a property, then this binding is invalidated on every keystroke, which causes a change to the text.
If you have a chain of bindings the default behavior could cause problems, because in the middle of the editing values may be not valid.
Ok, I know I could create an uni-directional binding from the property to the textfield and register a change listener to get informed when the cursor leaves the field and update the property manually if necessary.
Is there an easy, elegant way to change this behavior so that the binding is only invalidated when the editing is complete, e.g. when the cursor leaves the field?
Thanks
I think you've pretty much described the only way to do it. Here's about the cleanest way I can see to implement it (using Java 8, though it's easy enough to convert the lambdas back to be JavaFX 2.2 compatible if you need):
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.binding.StringBinding;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class CommitBoundTextField extends Application {
#Override
public void start(Stage primaryStage) {
TextField tf1 = new TextField();
createCommitBinding(tf1).addListener((obs, oldText, newText) ->
System.out.printf("Text 1 changed from \"%s\" to \"%s\"%n", oldText, newText));
TextField tf2 = new TextField();
createCommitBinding(tf2).addListener((obs, oldText, newText) ->
System.out.printf("Text 2 changed from \"%s\" to \"%s\"%n", oldText, newText));
VBox root = new VBox(5, tf1, tf2);
Scene scene = new Scene(root, 250, 100);
primaryStage.setScene(scene);
primaryStage.show();
}
private StringBinding createCommitBinding(TextField textField) {
StringBinding binding = Bindings.createStringBinding(() -> textField.getText());
textField.addEventHandler(ActionEvent.ACTION, evt -> binding.invalidate());
textField.focusedProperty().addListener((obs, wasFocused, isFocused)-> {
if (! isFocused) binding.invalidate();
});
return binding ;
}
public static void main(String[] args) {
launch(args);
}
}
I realize that I am a little late with a response, but thought this might be useful to someone.
When using TextFields, I often attach a TextFormatter to help validate entries. You can attach a listener to the formatters' valueProperty. That property is updated when the text is committed, rather than on every keystroke.
Here's an example of what I am talking about using a TextField specialized for integer inputs. When you make edits in the text field, the changes will be reflected in the Label when you tap Enter, lose focus by clicking the button, switch to a different window, and so on.
import javafx.application.Application;
import javafx.beans.binding.StringBinding;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.beans.value.ObservableValue;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.control.TextFormatter;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.converter.IntegerStringConverter;
class IntTextField extends TextField {
private final IntegerProperty value;
TextFormatter<Integer> formatter;
public double getValue() {
return value.getValue();
}
public void setValue(int newValue) {
value.setValue(newValue);
}
public IntegerProperty valueProperty() {
return value;
}
public StringBinding getStringBinding () {
return value.asString();
}
IntTextField(int initValue) {
value = new SimpleIntegerProperty(initValue);
setText(initValue + "");
formatter = new TextFormatter(new IntegerStringConverter(), initValue);
formatter.valueProperty().addListener((ObservableValue<? extends Integer> obs,
Integer oldValue, Integer newValue) -> value.setValue(newValue));
setTextFormatter(formatter);
}
IntTextField() {
this(0);
}
}
public class TFBindingDemo extends Application {
#Override
public void start(Stage stage) {
stage.setTitle("TFBindingDemo");
IntTextField intTextField = new IntTextField(12345);
intTextField.setMaxWidth(150);
Label label = new Label("Type in the TextField");
label.textProperty().bind(intTextField.getStringBinding());
Button removeFocusButton = new Button("Click Here to Remove Focus");
VBox root = new VBox(20, intTextField, label, removeFocusButton);
root.setAlignment(Pos.CENTER);
root.setPadding(new Insets(20));
Scene scene = new Scene(root, 325, 200);
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch();
}
}

JavaFx removing from pane object when I am in this object's class

I don't know if anyone could understand my problem from the title, but here's more specific description. I have class, in which I created a FlowPane, where I added objects of another class(images packed inside VBoxes). Each VBox have ContextMenu, where is MenuItem "Remove File". My problem is, how to remove this object while beeing inside the VBox class. Here is a little part of my code:
//removed, entire code is below after edit
The code where I'm accessing my CustomPane (my class of FlowPane, with specified attributes) works, because I can remove object if I'm doing it by their indexes, but when I remove one of them, other's indexes changes, so I'm looking for another solution. I need to specifically remove the object of the class in the code.
Okay so here is so called sscce, which of I had no idea, since now:
package sscce;
import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.Label;
import javafx.scene.control.MenuItem;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.FlowPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
public class Sscce extends Application {
#Override
public void start(Stage primaryStage) {
CustomPane root = new CustomPane();
root.setPadding(new Insets(20));
root.setHgap(10);
root.setVgap(10);
for (int i = 0; i < 10; i++) {
RectangleBox recB = new RectangleBox();
root.getChildren().add(recB);
}
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
class RectangleBox extends VBox {
static int index = 0;
public RectangleBox() {
Rectangle rec = new Rectangle(150, 150);
rec.setFill(Color.GREEN);
StackPane sp = new StackPane();
sp.getChildren().add(rec);
Label label = new Label(Integer.toString(index));
index++;
sp.getChildren().add(label);
getChildren().add(sp);
final ContextMenu cm = new ContextMenu();
MenuItem removeRec = new MenuItem("Remove Rectangle");
removeRec.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent t) {
((CustomPane) getParent()).getPane().getChildren().remove(0); //here is the problem, I want this line to remove the rectangle I clicked on(now it's removing first element in the pane).
}
});
cm.getItems().add(removeRec);
createContextMenuEvent(cm, rec);
}
private void createContextMenuEvent(final ContextMenu cm, final Rectangle rec) {
addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent t) {
if (t.getButton() == MouseButton.SECONDARY) {
cm.show(rec, t.getScreenX(), t.getScreenY());
}
}
});
}
}
class CustomPane extends FlowPane {
public CustomPane() {
//setAlignment(Pos.CENTER);
setHgap(25);
setVgap(25);
setPadding(new Insets(20));
}
public CustomPane getPane() {
return this;
}
}
It should work after copy/paste this entire code to java project. So I removed everything that is not neccessary, and I have replaced images to rectangles, now this program looks kind of stupid;p
I added comment to a line I have problem with. I hope now it's a lot clearer than before.
try this:
((CustomPane) RectangleBox.this.getParent()).getChildren().remove(RectangleBox.this);
hope it helps.

JavaFx :Default Message for Empty ListView

When there is no record in any table it shows a message 'No content in table', which is by default functionality of TableView in JavaFx.
So here my question is, does the same can be possible with ListView in JavaFx ? Like, if there is no item in any ListView then it will show a message same as TableView, instead of a blank/empty fields.
You have to try this:-
listView.setPlaceholder(new Label("No Content In List"));
its 100% working....
JavaFX8 has a setPlaceholder(...) method for ListView.
In earlier versions, you need to roll your own somehow. This is a bit of a hack: it wraps the ListView in a stack pane, with a white rectangle and the placeholder displayed over the top of the list view. The placeholder and rectangle have their visible property bound, so they are only visible if the list is empty.
There may be easier ways that I'm not seeing right away...
import javafx.application.Application;
import javafx.beans.binding.Bindings;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.ListView;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
public class ListViewPlaceholderTest extends Application {
#Override
public void start(Stage primaryStage) {
final ListView<String> listView = new ListView<>();
final IntegerProperty counter = new SimpleIntegerProperty();
final Button addButton = new Button("Add item");
addButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
counter.set(counter.get()+1);
listView.getItems().add("Item "+counter.get());
}
});
final Button removeButton = new Button("Remove");
removeButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
listView.getItems().remove(listView.getSelectionModel().getSelectedIndex());
}
});
removeButton.disableProperty().bind(Bindings.equal(listView.getSelectionModel().selectedIndexProperty(), -1));
final HBox buttons = new HBox(5);
buttons.setPadding(new Insets(10));
buttons.getChildren().addAll(addButton, removeButton);
final BorderPane root = new BorderPane();
root.setCenter(createPlaceholderForListView(listView, new Label("No content in List")));
root.setBottom(buttons);
final Scene scene = new Scene(root, 600, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
private Node createPlaceholderForListView(ListView<?> listView, Node placeholder) {
final StackPane pane = new StackPane();
final Rectangle rect = new Rectangle(0, 0, Color.WHITE);
rect.widthProperty().bind(listView.widthProperty());
rect.heightProperty().bind(listView.heightProperty());
pane.getChildren().addAll(listView, rect, placeholder);
placeholder.visibleProperty().bind(Bindings.isEmpty(listView.getItems()));
rect.visibleProperty().bind(placeholder.visibleProperty());
rect.setMouseTransparent(true);
return pane ;
}
}
With fxml:
<ListView fx:id="foundContentList">
<placeholder>
<Label text="Nothing found" />
</placeholder>
</ListView>
Not entirely sure but I don't think there is a setPlaceholder method(to set the default message when no content in table) for ListView.
The workaround that I use is to create an Object in the list that indicate "No content" and show that on the listview and also disable it.
For example:
ObservableList noContent= FXCollections.observableArrayList("No content found");
ListView listView = new ListView(noContent);
listView.setDisable(true);

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