Dealing with null values in Cell - javafx-2

I'm having serious problems getting a JavaFX 2 TableView to deal with null values in my data. So much trouble in fact I've put together a simple demo of the problem which is shown below.
Essentially the problem is that some of my data may be null and coercing the null to a value, such as an empty string, is not valid, it must be null. In the real code I'm working on I have a null date value, to keep the example simple I've shown a null string below.
Rows 1 and 2 of the table have null values. The two columns are different, the first shows the behaviour of the TextFieldTableCell the second my implementation of an editable cell. Both show the same incorrect behaviour.
The current behaviour is this:
Click the cell to enter editing mode
Enter a value in the cell
Press enter to commit the edit
Nothing happens
At step 4 I would expect the onEditCommit handler for the column to get called but it isn't. Having a look at the source for javax.scene.control.TableCell the commit isn't happening because of the first line of commitEdit is:
if (! isEditing()) return;
It seems that because the cell is null the editing property never gets set to true although I admit I've not yet traced through all the code to see why it never get's switched to true.
Thanks as always for any help.
Example
Main Application
package example;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.control.cell.TextFieldTableCell;
import javafx.stage.Stage;
import javafx.util.Callback;
public class NullCellEditingExample extends Application {
private TableView table = new TableView();
private final ObservableList<Person> data =
FXCollections.observableArrayList( new Person(null, "Smith"), new Person("Isabella", null),
new Person("Ethan", "Williams"), new Person("Emma", "Jones"), new Person("Michael", "Brown"));
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage stage) {
Scene scene = new Scene(new Group());
TableColumn firstNameCol = createSimpleFirstNameColumn();
TableColumn lastNameCol = createLastNameColumn();
table.setItems(data);
table.getColumns().addAll(firstNameCol, lastNameCol);
table.setEditable(true);
((Group) scene.getRoot()).getChildren().addAll(table);
stage.setScene(scene);
stage.show();
}
private TableColumn createSimpleFirstNameColumn() {
TableColumn firstNameCol = new TableColumn("First Name");
firstNameCol.setMinWidth(100);
firstNameCol.setCellValueFactory(new PropertyValueFactory<Person, String>("firstName"));
firstNameCol.setCellFactory(TextFieldTableCell.forTableColumn());
firstNameCol.setOnEditCommit(new EventHandler<TableColumn.CellEditEvent<Person, String>>() {
#Override
public void handle(TableColumn.CellEditEvent<Person, String> t) {
((Person) t.getTableView().getItems().get(t.getTablePosition().getRow())).setFirstName(t.getNewValue());
}
});
return firstNameCol;
}
private TableColumn createLastNameColumn() {
Callback<TableColumn, TableCell> editableFactory = new Callback<TableColumn, TableCell>() {
#Override
public TableCell call(TableColumn p) {
return new EditingCell();
}
};
TableColumn lastNameCol = new TableColumn("Last Name");
lastNameCol.setMinWidth(100);
lastNameCol.setCellValueFactory(new PropertyValueFactory<Person, String>("lastName"));
lastNameCol.setCellFactory(editableFactory);
lastNameCol.setOnEditCommit(new EventHandler<TableColumn.CellEditEvent<Person, String>>() {
#Override
public void handle(TableColumn.CellEditEvent<Person, String> t) {
t.getRowValue().setLastName(t.getNewValue());
}
});
return lastNameCol;
}
}
Editing Cell
package example;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.EventHandler;
import javafx.scene.control.TableCell;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
public class EditingCell extends TableCell<Person, String> {
private TextField textField;
public EditingCell() {
}
#Override
public void startEdit() {
super.startEdit();
if( textField == null ) {
createTextField();
}
setText(null);
setGraphic(textField);
textField.selectAll();
}
#Override
public void cancelEdit() {
super.cancelEdit();
setText((String) getItem());
setGraphic(null);
}
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (isEditing()) {
if (textField != null) {
textField.setText(getString());
}
setText(null);
setGraphic(textField);
} else {
setText(getString());
setGraphic(null);
}
}
}
private void createTextField() {
textField = new TextField(getString());
textField.setMinWidth(this.getWidth() - this.getGraphicTextGap() * 2);
textField.focusedProperty().addListener(new ChangeListener<Boolean>() {
#Override
public void changed(ObservableValue<? extends Boolean> arg0, Boolean arg1, Boolean arg2) {
if (!arg2) { commitEdit(textField.getText()); }
}
});
textField.setOnKeyReleased(new EventHandler<KeyEvent>() {
#Override
public void handle(KeyEvent t) {
if (t.getCode() == KeyCode.ENTER) {
String value = textField.getText();
if (value != null) { commitEdit(value); } else { commitEdit(null); }
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
}
});
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
}
Person
package example;
import javafx.beans.property.SimpleStringProperty;
public class Person {
private final SimpleStringProperty firstName;
private final SimpleStringProperty lastName;
public Person(String firstName, String lastName) {
this.firstName = new SimpleStringProperty(firstName);
this.lastName = new SimpleStringProperty(lastName);
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String firstName) {
this.firstName.set(firstName);
}
public SimpleStringProperty firstNameProperty() {
return firstName;
}
public String getLastName() {
return lastName.get();
}
public void setLastName(String lastName) {
this.lastName.set(lastName);
}
public SimpleStringProperty lastNameProperty() {
return lastName;
}
}

Since posting I found another question that is basically identical. They took the approach of always just avoiding null values which is fine for strings (e.g. use an empty string) but not acceptable for dates or other data types where the is no obvious "empty" value.
The solution is to pass a value of false into the super.updateItem call in the EditingCell.updateItem method. I've put together a full write up of this if anyone is interested in the complete analysis.

Related

Find changed object in JavaFX ObservableArrayList

It took me way too long to set up a listener on one property of the objects in my Observablelist and add a listener to it.
ObservableList<Track> observableResult = FXCollections.observableArrayList((Track tr)-> new Observable[]{tr.selectedProperty()});
observableResult.addListener(new ListChangeListener<Track>() {
#Override
public void onChanged(Change<? extends Track> c) {
c.next();
for(Track k : c.getAddedSubList()){
System.out.println(k.getTrackName());
}
}
});
But I can't seem to be able to locate the actual object the change has been made to. The Change class only appears to support added and removed members, which don't get triggered by the actual changes inside them.
I have a workaround for this, just calling another method that would loop trough the entire ObservableArrayList and get for example, only the selected items, but that gets pretty expensive after I have a couple of thousand objects. Finding the source members that got changed would allow me to just push them to another array and save a bunch of overhead.
You can call getFrom() on the change to get the index of the changed item. I don't think there's a way to actually figure out which property changed (if you have more than one property listed in the extractor) or get the old value, but maybe this is enough.
If you need more, you could consider registering your own listeners with the list to track, which would be tricky but not impossible.
Here's an SSCCE demonstrating the getFrom() call:
import java.util.Random;
import java.util.stream.IntStream;
import javafx.beans.Observable;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.collections.FXCollections;
import javafx.collections.ListChangeListener.Change;
import javafx.collections.ObservableList;
public class ListChangeListenerTest {
public static void main(String[] args) {
ObservableList<Item> itemList = FXCollections.observableArrayList(item -> new Observable[]{item.valueProperty()});
itemList.addListener((Change<? extends Item> c) -> {
while (c.next()) {
if (c.wasUpdated()) {
int index = c.getFrom();
System.out.println("Updated item at "+index+" new value is "+itemList.get(index).getValue());
}
}
});
IntStream.rangeClosed(1, 1000).mapToObj(Item::new).forEach(itemList::add);
Random rng = new Random();
itemList.get(rng.nextInt(itemList.size())).setValue(rng.nextInt(10000));
}
public static class Item {
private final IntegerProperty value = new SimpleIntegerProperty();
public Item(int value) {
setValue(value);
}
public final IntegerProperty valueProperty() {
return this.value;
}
public final int getValue() {
return this.valueProperty().get();
}
public final void setValue(final int value) {
this.valueProperty().set(value);
}
}
}
Here's a version that manages the listeners on the property manually. Note that
This doesn't use an extractor on the list
The property in the Item bean is constructed passing a reference to the bean that owns the property. This allows the listener on the property to get a reference to the Item (via a bit of ugly downcasting)
This gives a bit more flexibility; e.g. if you wanted to check modifications on multiple properties and perform different actions, this would allow this. As you can see, the listener can also access the old value.
import java.util.Random;
import java.util.stream.IntStream;
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.ListChangeListener.Change;
import javafx.collections.ObservableList;
public class ListChangeListenerTest {
public static void main(String[] args) {
ChangeListener<Number> valueListener = (obs, oldValue, newValue) -> {
Item item = (Item) ((Property<?>) obs).getBean();
System.out.println("Value for "+item+" changed from " + oldValue + " to "+newValue);
};
ObservableList<Item> itemList = FXCollections.observableArrayList();
itemList.addListener((Change<? extends Item> change) -> {
while (change.next()) {
if (change.wasAdded()) {
for (Item item : change.getAddedSubList()) {
item.valueProperty().addListener(valueListener);
}
}
if (change.wasRemoved()) {
for (Item item : change.getRemoved()) {
item.valueProperty().removeListener(valueListener);
}
}
}
});
IntStream.rangeClosed(1, 1000).mapToObj(Item::new).forEach(itemList::add);
Random rng = new Random();
itemList.get(rng.nextInt(itemList.size())).setValue(rng.nextInt(10000));
}
public static class Item {
private final IntegerProperty value = new SimpleIntegerProperty(this, "value");
private final String id ;
public Item(int value) {
id = "Item "+value ;
setValue(value);
}
public final IntegerProperty valueProperty() {
return this.value;
}
public final int getValue() {
return this.valueProperty().get();
}
public final void setValue(final int value) {
this.valueProperty().set(value);
}
#Override
public String toString() {
return id ;
}
}
}
Finally, if you want to account for "bulk" updates, you need to implement ObservableList yourself. You can do this by subclassing ModifiableObservableListBase, and the basic idea is pretty straightforward. The implementation is made a bit tedious by having to create the Change object representing the update, but it's not too bad. Here's an example that allows updating a contiguous range:
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.function.Consumer;
import javafx.collections.ListChangeListener.Change;
import javafx.collections.ModifiableObservableListBase;
public class UpdatingObservableList<T> extends ModifiableObservableListBase<T> {
private final List<T> list ;
public UpdatingObservableList(List<T> list) {
this.list = list ;
}
public UpdatingObservableList() {
this(new ArrayList<>());
}
public void updateSublist(int start, int end, Consumer<T> updater) {
if (start < 0) throw new ArrayIndexOutOfBoundsException("Start ("+start+") cannot be < 0");
if (end < start) throw new IllegalArgumentException("End ("+end+") cannot be less than start ("+start+")");
if (end > size()) throw new ArrayIndexOutOfBoundsException("End ("+end+") cannot be greater than list size ("+size()+")");
for (T element : list.subList(start, end)) {
updater.accept(element);
}
fireChange(createUpdate(start, end));
}
#Override
public T get(int index) {
return list.get(index);
}
#Override
public int size() {
return list.size();
}
#Override
protected void doAdd(int index, T element) {
list.add(index, element);
}
#Override
protected T doSet(int index, T element) {
return list.set(index, element);
}
#Override
protected T doRemove(int index) {
return list.remove(index);
}
private Change<T> createUpdate(int start, int end) {
return new Change<T>(this) {
private boolean initialState = true ;
#Override
public boolean next() {
if (initialState) {
initialState = false ;
return true ;
}
return false ;
}
#Override
public void reset() {
initialState = true ;
}
#Override
public int getFrom() {
checkState();
return start ;
}
#Override
public int getTo() {
checkState();
return end ;
}
#Override
public List<T> getAddedSubList() {
checkState();
return Collections.emptyList();
}
#Override
public List<T> getRemoved() {
checkState();
return Collections.emptyList();
}
#Override
protected int[] getPermutation() {
checkState();
return new int[0];
}
#Override
public boolean wasAdded() {
checkState();
return false ;
}
#Override
public boolean wasRemoved() {
checkState();
return false ;
}
#Override
public boolean wasUpdated() {
return true ;
}
#Override
public boolean wasPermutated() {
checkState();
return false ;
}
#Override
public int getRemovedSize() {
checkState();
return 0 ;
}
#Override
public int getAddedSize() {
checkState();
return 0 ;
}
private void checkState() {
if (initialState) {
throw new IllegalStateException("Must call Change.next()");
}
}
};
}
}
and here's a version of the test class that uses this. Note that the update is performed via the list:
import java.util.Random;
import java.util.stream.IntStream;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.collections.ListChangeListener.Change;
public class ListChangeListenerTest {
public static void main(String[] args) {
UpdatingObservableList<Item> itemList = new UpdatingObservableList<Item>();
itemList.addListener((Change<? extends Item> change) -> {
while (change.next()) {
if (change.wasUpdated()) {
for (int i = change.getFrom() ; i < change.getTo() ; i++) {
System.out.println(itemList.get(i) + " updated - new value: "+itemList.get(i).getValue());
}
}
}
});
IntStream.rangeClosed(1, 1000).mapToObj(Item::new).forEach(itemList::add);
Random rng = new Random();
int start = rng.nextInt(itemList.size());
int end = Math.min(itemList.size(), start + 1 + rng.nextInt(15));
itemList.updateSublist(start, end, item -> item.setValue(rng.nextInt(10000)));
}
public static class Item {
private final IntegerProperty value = new SimpleIntegerProperty(this, "value");
private final String id ;
public Item(int value) {
id = "Item "+value ;
setValue(value);
}
public final IntegerProperty valueProperty() {
return this.value;
}
public final int getValue() {
return this.valueProperty().get();
}
public final void setValue(final int value) {
this.valueProperty().set(value);
}
#Override
public String toString() {
return id ;
}
}
}

Java fx frop drag and drop issue

How to do drag and drop within one listview
I have only one list view (Ed. "player")
My requirement is to move up and down in the same player list
Please find the code i have used
(Not: I am using jdk 1.7 with default javafx)
Example:(player = listView)
listView.setOnDragDetected(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
Dragboard dragBoard = listView.startDragAndDrop(TransferMode.MOVE);
ClipboardContent content = new ClipboardContent();
content.putString(listView.getSelectionModel().getSelectedItem().getValue());
dragBoard.setContent(content);
}
});
listView.setOnDragDone(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent dragEvent) {
System.out.println("setOnDragDone left");
}
});
listView.setOnDragEntered(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent dragEvent) {
System.out.println("setOnDragEntered left");
}
});
listView.setOnDragExited(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent dragEvent) {
System.out.println("setOnDragExited left");
listView.setBlendMode(null);
}
});
listView.setOnDragOver(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent dragEvent) {
System.out.println("setOnDragOver left");
dragEvent.acceptTransferModes(TransferMode.MOVE);
}
});
listView.setOnDragDropped(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent dragEvent) {
String context = dragEvent.getDragboard().getString();
dragEvent.setDropCompleted(true);
}
}
});
I am new to javafx
Would you please help on this regard
Don't register the drag handlers on the ListView: you will have no way of knowing which cells the drag started and ended on. Instead, you need to register the handlers on the cells. The details get a little tricky, but the basic idea is to create a cell factory in which you create the custom cells; here you can set up the drag and drop handlers.
Here's an example:
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javafx.application.Application;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.ListCell;
import javafx.scene.control.ListView;
import javafx.scene.input.ClipboardContent;
import javafx.scene.input.DragEvent;
import javafx.scene.input.Dragboard;
import javafx.scene.input.MouseEvent;
import javafx.scene.input.TransferMode;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
import javafx.util.Callback;
public class DragAndDropListView extends Application {
#Override
public void start(Stage primaryStage) {
final ListView<String> listView = new ListView<>();
for (int i=1; i<=20; i++) {
listView.getItems().add("Item "+i);
}
final IntegerProperty dragFromIndex = new SimpleIntegerProperty(-1);
listView.setCellFactory(new Callback<ListView<String>, ListCell<String>>() {
#Override
public ListCell<String> call(ListView<String> lv) {
final ListCell<String> cell = new ListCell<String>() {
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
} else {
setText(item);
}
}
};
cell.setOnDragDetected(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
if (! cell.isEmpty()) {
dragFromIndex.set(cell.getIndex());
Dragboard db = cell.startDragAndDrop(TransferMode.MOVE);
ClipboardContent cc = new ClipboardContent();
cc.putString(cell.getItem());
db.setContent(cc);
// Java 8 only:
// db.setDragView(cell.snapshot(null, null));
}
}
});
cell.setOnDragOver(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent event) {
if (dragFromIndex.get() >= 0 && dragFromIndex.get() != cell.getIndex()) {
event.acceptTransferModes(TransferMode.MOVE);
}
}
});
// highlight drop target by changing background color:
cell.setOnDragEntered(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent event) {
if (dragFromIndex.get() >= 0 && dragFromIndex.get() != cell.getIndex()) {
// should really set a style class and use an external style sheet,
// but this works for demo purposes:
cell.setStyle("-fx-background-color: gold;");
}
}
});
// remove highlight:
cell.setOnDragExited(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent event) {
cell.setStyle("");
}
});
cell.setOnDragDropped(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent event) {
int dragItemsStartIndex ;
int dragItemsEndIndex ;
int direction ;
if (cell.isEmpty()) {
dragItemsStartIndex = dragFromIndex.get();
dragItemsEndIndex = listView.getItems().size();
direction = -1;
} else {
if (cell.getIndex() < dragFromIndex.get()) {
dragItemsStartIndex = cell.getIndex();
dragItemsEndIndex = dragFromIndex.get() + 1 ;
direction = 1 ;
} else {
dragItemsStartIndex = dragFromIndex.get();
dragItemsEndIndex = cell.getIndex() + 1 ;
direction = -1 ;
}
}
List<String> rotatingItems = listView.getItems().subList(dragItemsStartIndex, dragItemsEndIndex);
List<String> rotatingItemsCopy = new ArrayList<>(rotatingItems);
Collections.rotate(rotatingItemsCopy, direction);
rotatingItems.clear();
rotatingItems.addAll(rotatingItemsCopy);
dragFromIndex.set(-1);
}
});
cell.setOnDragDone(new EventHandler<DragEvent>() {
#Override
public void handle(DragEvent event) {
dragFromIndex.set(-1);
listView.getSelectionModel().select(event.getDragboard().getString());
}
});
return cell ;
}
});
BorderPane root = new BorderPane();
root.setCenter(listView);
Scene scene = new Scene(root, 250, 400);
scene.getStylesheets().add(getClass().getResource("drag-and-drop-list.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
This will enable you to drag any element and drop it onto any other. For example dragging the third item in the list
and dropping it on the first item results in this:
In Java 8 you can also add the line
db.setDragView(cell.snapshot(null, null));
to the setOnDragDetected(...) method to get a better visual on the drag.

JavaFX 2 TableView how to update cell when object is changed

I'm creating a TableView to show information regarding a list of custom objects (EntityEvents).
The table view must have 2 columns.
First column to show the corresponding EntityEvent's name.
The second column would display a button. The button text deppends on a property of the EntityEvent. If the property is ZERO, it would be "Create", otherwise "Edit".
I managed to do it all just fine, except that I can't find a way to update the TableView line when the corresponding EntityEvent object is changed.
Very Important: I can't change the EntityEvent class to use JavaFX properties, since they are not under my control. This class uses PropertyChangeSupport to notify listeners when the monitored property is changed.
Note:
I realize that adding new elements to the List would PROBABLY cause the TableView to repaint itself, but that is not what I need. I say PROBABLY because I've read about some bugs that affect this behavior.
I tried using this approach to force the repaint, by I couldn't make it work.
Does anyone knows how to do it?
Thanks very much.
Here is a reduced code example that illustrates the scenario:
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import javafx.application.Application;
import javafx.beans.property.ReadOnlyStringWrapper;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ContentDisplay;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableColumn.CellDataFeatures;
import javafx.scene.control.TableView;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import javafx.util.Callback;
public class Main extends Application {
//=============================================================================================
public class EntityEvent {
private String m_Name;
private PropertyChangeSupport m_NamePCS = new PropertyChangeSupport(this);
private int m_ActionCounter;
private PropertyChangeSupport m_ActionCounterPCS = new PropertyChangeSupport(this);
public EntityEvent(String name, int actionCounter) {
m_Name = name;
m_ActionCounter = actionCounter;
}
public String getName() {
return m_Name;
}
public void setName(String name) {
String lastName = m_Name;
m_Name = name;
System.out.println("Name changed: " + lastName + " -> " + m_Name);
m_NamePCS.firePropertyChange("Name", lastName, m_Name);
}
public void addNameChangeListener(PropertyChangeListener listener) {
m_NamePCS.addPropertyChangeListener(listener);
}
public int getActionCounter() {
return m_ActionCounter;
}
public void setActionCounter(int actionCounter) {
int lastActionCounter = m_ActionCounter;
m_ActionCounter = actionCounter;
System.out.println(m_Name + ": ActionCounter changed: " + lastActionCounter + " -> " + m_ActionCounter);
m_ActionCounterPCS.firePropertyChange("ActionCounter", lastActionCounter, m_ActionCounter);
}
public void addActionCounterChangeListener(PropertyChangeListener listener) {
m_ActionCounterPCS.addPropertyChangeListener(listener);
}
}
//=============================================================================================
private class AddPersonCell extends TableCell<EntityEvent, String> {
Button m_Button = new Button("Undefined");
StackPane m_Padded = new StackPane();
AddPersonCell(final TableView<EntityEvent> table) {
m_Padded.setPadding(new Insets(3));
m_Padded.getChildren().add(m_Button);
m_Button.setOnAction(new EventHandler<ActionEvent>() {
#Override public void handle(ActionEvent actionEvent) {
// Do something
}
});
}
#Override protected void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (!empty) {
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
setGraphic(m_Padded);
m_Button.setText(item);
}
}
}
//=============================================================================================
private ObservableList<EntityEvent> m_EventList;
//=============================================================================================
#SuppressWarnings("unchecked")
#Override
public void start(Stage primaryStage) {
primaryStage.setTitle("Table View test.");
VBox container = new VBox();
m_EventList = FXCollections.observableArrayList(
new EntityEvent("Event 1", -1),
new EntityEvent("Event 2", 0),
new EntityEvent("Event 3", 1)
);
final TableView<EntityEvent> table = new TableView<EntityEvent>();
table.setItems(m_EventList);
TableColumn<EntityEvent, String> eventsColumn = new TableColumn<>("Events");
TableColumn<EntityEvent, String> actionCol = new TableColumn<>("Actions");
actionCol.setSortable(false);
eventsColumn.setCellValueFactory(new Callback<CellDataFeatures<EntityEvent, String>, ObservableValue<String>>() {
public ObservableValue<String> call(CellDataFeatures<EntityEvent, String> p) {
EntityEvent event = p.getValue();
event.addActionCounterChangeListener(new PropertyChangeListener() {
#Override
public void propertyChange(PropertyChangeEvent event) {
// TODO: I'd like to update the table cell information.
}
});
return new ReadOnlyStringWrapper(event.getName());
}
});
actionCol.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<EntityEvent, String>, ObservableValue<String>>() {
#Override
public ObservableValue<String> call(TableColumn.CellDataFeatures<EntityEvent, String> ev) {
String text = "NONE";
if(ev.getValue() != null) {
text = (ev.getValue().getActionCounter() != 0) ? "Edit" : "Create";
}
return new ReadOnlyStringWrapper(text);
}
});
// create a cell value factory with an add button for each row in the table.
actionCol.setCellFactory(new Callback<TableColumn<EntityEvent, String>, TableCell<EntityEvent, String>>() {
#Override
public TableCell<EntityEvent, String> call(TableColumn<EntityEvent, String> personBooleanTableColumn) {
return new AddPersonCell(table);
}
});
table.getColumns().setAll(eventsColumn, actionCol);
table.setColumnResizePolicy(TableView.CONSTRAINED_RESIZE_POLICY);
// Add Resources Button
Button btnInc = new Button("+");
btnInc.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent ev) {
System.out.println("+ clicked.");
EntityEvent entityEvent = table.getSelectionModel().getSelectedItem();
if (entityEvent == null) {
System.out.println("No Event selected.");
return;
}
entityEvent.setActionCounter(entityEvent.getActionCounter() + 1);
// TODO: I expected the TableView to be updated since I modified the object.
}
});
// Add Resources Button
Button btnDec = new Button("-");
btnDec.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent ev) {
System.out.println("- clicked.");
EntityEvent entityEvent = table.getSelectionModel().getSelectedItem();
if (entityEvent == null) {
System.out.println("No Event selected.");
return;
}
entityEvent.setActionCounter(entityEvent.getActionCounter() - 1);
// TODO: I expected the TableView to be updated since I modified the object.
}
});
container.getChildren().add(table);
container.getChildren().add(btnInc);
container.getChildren().add(btnDec);
Scene scene = new Scene(container, 300, 600, Color.WHITE);
primaryStage.setScene(scene);
primaryStage.show();
}
//=============================================================================================
public Main() {
}
//=============================================================================================
public static void main(String[] args) {
launch(Main.class, args);
}
}
Try the javafx.beans.property.adapter classes, particularly JavaBeanStringProperty and JavaBeanIntegerProperty. I haven't used these, but I think you can do something like
TableColumn<EntityEvent, Integer> actionCol = new TableColumn<>("Actions");
actionCol.setCellValueFactory(new Callback<TableColumn.CellDataFeatures<EntityEvent, Integer> ev) {
return new JavaBeanIntegerPropertyBuilder().bean(ev.getValue()).name("actionCounter").build();
});
// ...
public class AddPersonCell extends TableCell<EntityEvent, Integer>() {
final Button button = new Button();
public AddPersonCell() {
setPadding(new Insets(3));
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
button.setOnAction(...);
}
#Override
public void updateItem(Integer actionCounter, boolean empty) {
if (empty) {
setGraphic(null);
} else {
if (actionCounter.intValue()==0) {
button.setText("Create");
} else {
button.setText("Add");
}
setGraphic(button);
}
}
}
As I said, I haven't used the Java bean property adapter classes, but the idea is that they "translate" property change events to JavaFX change events. I just typed this in here without testing, but it should at least give you something to start with.
UPDATE: After a little experimenting, I don't think this approach will work if your EntityEvent is really set up the way you showed it in your code example. The standard Java beans bound properties pattern (which the JavaFX property adapters rely on) has a single property change listener and an addPropertyChangeListener(...) method. (The listeners can query the event to see which property changed.)
I think if you do
public class EntityEvent {
private String m_Name;
private PropertyChangeSupport pcs = new PropertyChangeSupport(this);
private int m_ActionCounter;
public EntityEvent(String name, int actionCounter) {
m_Name = name;
m_ActionCounter = actionCounter;
}
public String getName() {
return m_Name;
}
public void setName(String name) {
String lastName = m_Name;
m_Name = name;
System.out.println("Name changed: " + lastName + " -> " + m_Name);
pcs.firePropertyChange("name", lastName, m_Name);
}
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcs.addPropertyChangeListener(listener);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcs.removePropertyChangeListener(listener);
}
public int getActionCounter() {
return m_ActionCounter;
}
public void setActionCounter(int actionCounter) {
int lastActionCounter = m_ActionCounter;
m_ActionCounter = actionCounter;
System.out.println(m_Name + ": ActionCounter changed: " + lastActionCounter + " -> " + m_ActionCounter);
pcs.firePropertyChange("ActionCounter", lastActionCounter, m_ActionCounter);
}
}
it will work with the adapter classes above. Obviously, if you have existing code calling the addActionChangeListener and addNameChangeListener methods you would want to keep those existing methods and the existing property change listeners, but I see no reason you can't have both.

Working with DateTime as StringProperty

I have defined a DateTime field as StringProperty in my model to display date. I have few rows where the date column is empty in database and have defined a cellfactory to display the date in a desired format & blank for empty rows. My problem starts when i try to update one of those empty columns. The new date doesnt appear. It works for the rows where there is already a date value present.
Part of cellfactory:
txtfld.setOnKeyPressed(new EventHandler<KeyEvent>() {
#Override
public void handle(KeyEvent t) {
if (t.getCode() == KeyCode.ENTER) {
if(txtfld.getText().length() == 0) {
commitEdit(null);
} else {
commitEdit((new DateTime(txtfld.getText(),"dd/MM/yyyy")).toString());
}
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
}
});
And the part where I am updating the model:
col_Purchase_DT.setOnEditCommit(new EventHandler<CellEditEvent<Purchase, String>>() {
#Override
public void handle(CellEditEvent<Purchase, String> tbl) {
(tbl.getTableView().getItems().get(tbl.getTablePosition().getRow())).setDOB(tbl.getNewValue());
}
});
I have figured it out that after updating the empty cell with a date col_Purchase_DT.setOnEditCommit() is not called. But is works for non-empty cell. I am using JodaTime for datetime.
I cannot update the second row. But it works perfectly for first & third row.
Any pointers will be helpful.
You seem to be doing way too much coding for this. There's a TextFieldTableCell class that you can use for creating editable cells, and it handles all the wiring for you. Here's an example, based on the usual example from the tutorial. I used the Java 8 java.time.LocalDate for the date column, but the same idea can be applied for JodaTime (I'm just not familiar with the API).
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeParseException;
import javafx.application.Application;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.control.cell.TextFieldTableCell;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
import javafx.util.StringConverter;
public class TableWithEditableDateColumn extends Application {
#Override
public void start(Stage primaryStage) {
final TableView<Person> table = new TableView<>();
final TableColumn<Person, String> firstNameCol = createTableColumn("firstName", "First Name", String.class);
final TableColumn<Person, String> lastNameCol = createTableColumn("lastName", "Last Name", String.class);
final TableColumn<Person, LocalDate> birthdayCol = createTableColumn("birthday", "Birthday", LocalDate.class);
final DateTimeFormatter dateFormat = DateTimeFormatter.ofPattern("dd/MM/yyyy");
firstNameCol.setCellFactory(TextFieldTableCell.forTableColumn());
lastNameCol.setCellFactory(TextFieldTableCell.forTableColumn());
birthdayCol.setCellFactory(TextFieldTableCell.forTableColumn(new StringConverter<LocalDate>() {
#Override
public String toString(LocalDate t) {
if (t==null) {
return "" ;
} else {
return dateFormat.format(t);
}
}
#Override
public LocalDate fromString(String string) {
try {
return LocalDate.parse(string, dateFormat);
} catch (DateTimeParseException exc) {
return null ;
}
}
}));
final ObservableList<Person> data =
FXCollections.observableArrayList(
new Person("Jacob", "Smith", LocalDate.parse("14/03/1975", dateFormat)),
new Person("Isabella", "Johnson", LocalDate.parse("27/09/1982", dateFormat)),
new Person("Ethan", "Williams", null),
new Person("Emma", "Jones", LocalDate.parse("12/07/1979", dateFormat)),
new Person("Michael", "Brown", LocalDate.parse("19/10/1984", dateFormat))
);
table.getColumns().addAll(firstNameCol, lastNameCol, birthdayCol);
table.setItems(data);
table.setEditable(true);
final BorderPane root = new BorderPane();
root.setCenter(table);
final Scene scene = new Scene(root, 600, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
private <T> TableColumn<Person, T> createTableColumn(String property, String title, Class<T> type) {
TableColumn<Person, T> col = new TableColumn<>(title);
col.setCellValueFactory(new PropertyValueFactory<>(property));
col.setEditable(true);
col.setPrefWidth(100);
return col ;
}
public static class Person {
private final StringProperty firstName ;
private final StringProperty lastName ;
private final ObjectProperty<LocalDate> birthday ;
public Person(String firstName, String lastName, LocalDate birthday) {
this.firstName = new SimpleStringProperty(this, "firstName", firstName);
this.lastName = new SimpleStringProperty(this, "lastName", lastName);
this.birthday = new SimpleObjectProperty<>(this, "birthday", birthday);
}
public String getFirstName() {
return firstName.get();
}
public void setFirstName(String value) {
firstName.set(value);
}
public StringProperty firstNameProperty() {
return firstName;
}
public String getLastName() {
return lastName.get();
}
public void setLastName(String value) {
lastName.set(value);
}
public StringProperty lastNameProperty() {
return lastName;
}
public LocalDate getBirthday() {
return birthday.get();
}
public void setBirthday(LocalDate value) {
birthday.set(value);
}
public ObjectProperty birthdayProperty() {
return birthday;
}
}
public static void main(String[] args) {
launch(args);
}
}
onEditCommit is not fired if an update happens on a null value.
Here is the answer: http://www.wobblycogs.co.uk/index.php/computing/javafx/145-editing-null-data-values-in-a-cell-with-javafx-2

Javafx, get the object referenced by a TableCell

I have the following Callback listening on the selected Cell of a TableView:
Callback<TableColumn<MyFTPFile,String>, TableCell<MyFTPFile,String>> cellFactory =
new Callback<TableColumn<MyFTPFile,String>, TableCell<MyFTPFile,String>>() {
public TableCell<MyFTPFile,String> call(TableColumn<MyFTPFile,String> p) {
TableCell<MyFTPFile,String> cell = new TableCell<MyFTPFile, String>() {
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
setText(empty ? null : getString());
setGraphic(null);
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
};
cell.addEventFilter(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
if (event.getClickCount() > 1) {
TableCell<MyFTPFile,String> c = (TableCell<MyFTPFile,String>) event.getSource();
ftpObservablelist = MyFTPClient.getInstance().getFtpObservableList();
ftpTable.setItems(ftpObservablelist);
}
}
});
Now, I would like to get the MyFTPFile object which is referenced by the cell, which is doubleclicked, so that i can pass it to another class and do stuff... Any Idea how to do that???
Thanks in advance.
The MyFTPFile object is associated with the cell's row, so, as the asker pointed out in his comment, it is retrievable via cell.getTableRow().getItem().
At first I thought this should be cell.getItem(), which returns the data value associated with the cell. However, most of the time, the cell data value will be a property of the backing item rather than the object itself (for example a filename field of a MyFTPFile object).
Executable sample for the curious:
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.scene.control.cell.TextFieldTableCell;
import javafx.scene.input.MouseEvent;
import javafx.stage.Stage;
import javafx.util.Callback;
public class TableClickListener extends Application {
public static void main(String[] args) {
launch(args);
}
class FTPTableCell<S, T> extends TextFieldTableCell<S, T> {
FTPTableCell() {
super();
addEventFilter(MouseEvent.MOUSE_CLICKED, new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent event) {
if (event.getClickCount() > 1 && getItem() != null) {
System.out.println("Sending " + getTableRow().getItem() + " to the FTP client");
}
}
});
}
}
final Callback<TableColumn<MyFTPFile, String>, TableCell<MyFTPFile, String>> FTP_TABLE_CELL_FACTORY =
new Callback<TableColumn<MyFTPFile, String>, TableCell<MyFTPFile, String>>() {
public TableCell<MyFTPFile, String> call(TableColumn<MyFTPFile, String> p) {
return new FTPTableCell<>();
}
};
#Override
public void start(final Stage stage) {
final TableView<MyFTPFile> table = new TableView<>();
final TableColumn<MyFTPFile, String> filenameColumn = new TableColumn<>("Filename");
filenameColumn.setCellValueFactory(new PropertyValueFactory<MyFTPFile, String>("filename"));
filenameColumn.setCellFactory(FTP_TABLE_CELL_FACTORY);
filenameColumn.setMinWidth(150);
final TableColumn<MyFTPFile, String> ratingColumn = new TableColumn<>("Rating");
ratingColumn.setCellValueFactory(new PropertyValueFactory<MyFTPFile, String>("rating"));
ratingColumn.setCellFactory(FTP_TABLE_CELL_FACTORY);
ratingColumn.setMinWidth(20);
table.getColumns().setAll(filenameColumn, ratingColumn);
table.getItems().setAll(
new MyFTPFile("xyzzy.txt", 10),
new MyFTPFile("management_report.doc", 1),
new MyFTPFile("flower.png", 7)
);
table.setColumnResizePolicy(TableView.CONSTRAINED_RESIZE_POLICY);
stage.setScene(new Scene(new Group(table)));
stage.show();
}
public class MyFTPFile {
private final String filename;
private final int rating;
MyFTPFile(String filename, int rating) {
this.filename = filename;
this.rating = rating;
}
public String getFilename() {
return filename;
}
public int getRating() {
return rating;
}
#Override
public String toString() {
return "MyFTPFile{" +
"filename='" + filename + '\'' +
", rating=" + rating +
'}';
}
}
}

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