JavaFx Create Table Cell Accepts numbers only? - javafx

Question

I have TableView with column inside it that must only accept numbers.
and I added onMouseClickListener to enter edit mode on the mouse click instead of double click on the cell
I want a way to not allowing the user to enter any character except numbers. My code is:
Callback<TableColumn<DailyDetails, String>, TableCell<DailyDetails, String>> defaultCellFactory
= TextFieldTableCell.<DailyDetails>forTableColumn();
dailyCredit.setCellFactory(column -> {
TableCell<DailyDetails, String> cell = defaultCellFactory.call(column);
cell.setOnMouseClicked(e -> {
if (!cell.isEditing() && !cell.isEmpty()) {
cell.getTableView().edit(cell.getIndex(), column);
}
});
return cell;
});
I implemented Table cell from the scratch:
class NumberCell extends TableCell<DailyDetails, String> {
private TextField textField;
public NumberCell() {
}
#Override
public void startEdit() {
super.startEdit();
if (textField == null) {
createTextField();
}
setGraphic(textField);
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
textField.selectAll();
}
#Override
public void cancelEdit() {
super.cancelEdit();
setText(String.valueOf(getItem()));
setContentDisplay(ContentDisplay.TEXT_ONLY);
}
#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());
}
setGraphic(textField);
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
} else {
setText(getString());
setContentDisplay(ContentDisplay.TEXT_ONLY);
}
}
}
private void createTextField() {
textField = new TextField(getString());
//textField.setMinWidth(this.getWidth() - this.getGraphicTextGap() * 2);
textField.lengthProperty().addListener(new ChangeListener<Number>(){
#Override
public void changed(ObservableValue<? extends Number> observable, Number oldValue, Number newValue) {
if (newValue.intValue() > oldValue.intValue()) {
char ch = textField.getText().charAt(oldValue.intValue());
// Check if the new character is the number or other's
if (!(ch >= '0' && ch <= '9' )) {
// if it's not number then just setText to previous one
textField.setText(textField.getText().substring(0,textField.getText().length()-1));
}
}
}
});
}
private String getString() {
return getItem() == null ? "" : getItem().toString();
}
}
Callback<TableColumn<DailyDetails, String>,
TableCell<DailyDetails, String>> cellFactory
= (TableColumn<DailyDetails, String> p) -> new NumberCell();
dailyDebit.setCellFactory(cellFactory);
the problem is i lost the on mouse listener cell.setOnMouseClicked!!!
how do i get the cell again to assign the listener ???

Answer 1

Just for driving the new api into everybody's brain: a full example with a slightly different TextFormatter (than in the other answer) that is Locale-aware and (dirtily!) hooked into core TextFieldTableCell, can be used in any custom editing TableCell as well:
/**
* Example of how-to use a TextFormatter in a editing TableCell.
*/
public class CellFormatting extends Application {
private Parent getContent() {
ObservableList<IntData> data = FXCollections.observableArrayList(
new IntData(1), new IntData(2), new IntData(3)
);
TableView<IntData> table = new TableView<>(data);
table.setEditable(true);
TableColumn<IntData, Integer> column = new TableColumn<>("Data");
column.setCellValueFactory(new PropertyValueFactory("data"));
// core default: will throw exception on illegal values
// column.setCellFactory(TextFieldTableCell.forTableColumn(new IntegerStringConverter()));
NumberFormat format = NumberFormat.getIntegerInstance();
UnaryOperator<TextFormatter.Change> filter = c -> {
if (c.isContentChange()) {
ParsePosition parsePosition = new ParsePosition(0);
// NumberFormat evaluates the beginning of the text
format.parse(c.getControlNewText(), parsePosition);
if (parsePosition.getIndex() == 0 ||
parsePosition.getIndex() < c.getControlNewText().length()) {
// reject parsing the complete text failed
return null;
}
}
return c;
};
column.setCellFactory(c -> new ValidatingTextFieldTableCell<>(
// note: each cell needs its own formatter
// see comment by #SurprisedCoconut
new TextFormatter<Integer>(
// note: should use local-aware converter instead of core!
new IntegerStringConverter(), 0,
filter)));
table.getColumns().add(column);
VBox box = new VBox(table);
return box;
}
/**
* TextFieldTableCell that validates input with a TextFormatter.
* <p>
* Extends TextFieldTableCell, accesses super's private field reflectively.
*
*/
public static class ValidatingTextFieldTableCell<S, T> extends TextFieldTableCell<S, T> {
private TextFormatter<T> formatter;
private TextField textAlias;
public ValidatingTextFieldTableCell() {
this((StringConverter<T>)null);
}
public ValidatingTextFieldTableCell(StringConverter<T> converter) {
super(converter);
}
public ValidatingTextFieldTableCell(TextFormatter<T> formatter) {
super(formatter.getValueConverter());
this.formatter = formatter;
}
/**
* Overridden to install the formatter. <p>
*
* Beware: implementation detail! super creates and configures
* the textField lazy on first access, so have to install after
* calling super.
*/
#Override
public void startEdit() {
super.startEdit();
installFormatter();
}
private void installFormatter() {
if (formatter != null && isEditing() && textAlias == null) {
textAlias = invokeTextField();
textAlias.setTextFormatter(formatter);
}
}
private TextField invokeTextField() {
Class<?> clazz = TextFieldTableCell.class;
try {
Field field = clazz.getDeclaredField("textField");
field.setAccessible(true);
return (TextField) field.get(this);
} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException e) {
e.printStackTrace();
}
return null;
}
}
public static class IntData {
IntegerProperty data = new SimpleIntegerProperty(this, "data");
public IntData(int value) {
setData(value);
}
public void setData(int value) {
data.set(value);
}
public int getData() {
return data.get();
}
public IntegerProperty dataProperty() {
return data;
}
}
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setScene(new Scene(getContent()));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
BTW, the formatter is re-used from another question where the task at hand was to restrict input into a Spinner.

Answer 2

Use a TextFormatter on the TextField like this:
TextFormatter<String> formatter = new TextFormatter<String>( change -> {
change.setText(change.getText().replaceAll("[^0-9.,]", ""));
return change;
});
textField.setTextFormatter(formatter);
Works with Java8u40 upwards. Use e. g. the TableView example from the Oracle site as base.