“Accounting” Style Table Cell in JavaFX

Question

Is there a way to create "accounting" style cells in JavaFX tables? By accounting I mean having the dollar sign left-aligned and the values right-aligned in the cell. Here is what that looks like in Excel:

Here is what I tried so far:

public class PriceTableCell<S> extends TableCell<S, Long>
{
    public PriceTableCell()
    {
        final Label label = new Label("$");
        this.setAlignment(Pos.CENTER_RIGHT);
        this.setContentDisplay(ContentDisplay.LEFT);
        this.setGraphic(label);
    }

    @Override
    protected void updateItem(Long item, boolean empty)
    {
        if (item == null || empty)
        {
            this.setText(null);
            return;
        }

        this.setText(String.format(Locale.ENGLISH, "%,d.%02d", item / 100, Math.abs(item % 100)));
    }
}

Unfortunately I did not find a way to set separate alignments for graphic and text. JavaFX renders the above as follows:

Answer 1

Using two labels in an AnchorPane should work.

(Update: Following @kleopatra 's suggestion, I incorporated a DecimalFormat into this solution, which will (at least partially) localize the currency symbol, as well as the number of decimal digits, etc. This will make the assumption that the currency symbol is displayed to the left of the currency value, which isn't necessarily true for all currencies, but the assumption is somewhat implicit in the question anyway.)

public class PriceTableCell<S> extends TableCell<S, Long> {

    private final AnchorPane pane ;
    private final Label valueLabel ;
    // locale-aware currency format to use for formatting
    private DecimalFormat format;

    public PriceTableCell() {
        // grab an instance
        format = (DecimalFormat) NumberFormat.getCurrencyInstance();
        //get the currency symbol
        String symbol = format.getCurrency().getSymbol();
        // replace the currency symbol with an empty string
        DecimalFormatSymbols symbols = format.getDecimalFormatSymbols();
        symbols.setCurrencySymbol("");
        format.setDecimalFormatSymbols(symbols);

        Label currencySignLabel = new Label(symbol);
        valueLabel = new Label();
        pane = new AnchorPane(currencySignLabel, valueLabel);
        AnchorPane.setLeftAnchor(currencySignLabel, 0.0);
        AnchorPane.setRightAnchor(valueLabel, 0.0);
        setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
    }

    @Override
    protected void updateItem(Long price, boolean empty) {
        super.updateItem(price, empty);
        if (empty) {
            setGraphic(null);
        } else {
            // manual formatting 
            //String text = String.format("%,d.%02d", price / 100, Math.abs(price % 100));
            valueLabel.setText(format.format(price));
            setGraphic(pane);
        }
    }
}

Here is a SSCCE:

import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.NumberFormat;
import java.util.Random;
import java.util.function.Function;

import javafx.application.Application;
import javafx.beans.property.LongProperty;
import javafx.beans.property.SimpleLongProperty;
import javafx.beans.property.SimpleStringProperty;
import javafx.beans.property.StringProperty;
import javafx.beans.value.ObservableValue;
import javafx.scene.Scene;
import javafx.scene.control.ContentDisplay;
import javafx.scene.control.Label;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;

public class TableViewWithAccountingStyleCell extends Application {

    public static class PriceTableCell<S> extends TableCell<S, Long> {

        private final AnchorPane pane ;
        private final Label valueLabel ;
        // locale-aware currency format to use for formatting
        private DecimalFormat format;

        public PriceTableCell() {
            // grab an instance
            format = (DecimalFormat) NumberFormat.getCurrencyInstance();
            //get the currency symbol
            String symbol = format.getCurrency().getSymbol();
            // replace the currency symbol with an empty string
            DecimalFormatSymbols symbols = format.getDecimalFormatSymbols();
            symbols.setCurrencySymbol("");
            format.setDecimalFormatSymbols(symbols);

            Label currencySignLabel = new Label(symbol);
            valueLabel = new Label();
            pane = new AnchorPane(currencySignLabel, valueLabel);
            AnchorPane.setLeftAnchor(currencySignLabel, 0.0);
            AnchorPane.setRightAnchor(valueLabel, 0.0);
            setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
        }

        @Override
        protected void updateItem(Long price, boolean empty) {
            super.updateItem(price, empty);
            if (empty) {
                setGraphic(null);
            } else {
                // manual formatting 
                //String text = String.format("%,d.%02d", price / 100, Math.abs(price % 100));
                valueLabel.setText(format.format(price));
                setGraphic(pane);
            }
        }
    }

    public static class Item {
        private final StringProperty name = new SimpleStringProperty();
        private final LongProperty price = new SimpleLongProperty();

        public Item(String name, long price) {
            setName(name);
            setPrice(price);
        }

        public StringProperty nameProperty() {
            return name ;
        }

        public final String getName() {
            return nameProperty().get();
        }

        public final void setName(String name) {
            nameProperty().set(name);
        }

        public LongProperty priceProperty() {
            return price ;
        }

        public final long getPrice() {
            return priceProperty().get();
        }

        public final void setPrice(long price) {
            priceProperty().set(price);
        }
    }

    @Override
    public void start(Stage primaryStage) {
        TableView<Item> table = new TableView<>();
        table.getColumns().add(column("Item", Item::nameProperty));
        TableColumn<Item, Long> priceColumn = column("Price", item -> item.priceProperty().asObject());
        priceColumn.setPrefWidth(300);

        priceColumn.setCellFactory(tc -> new PriceTableCell<>());

        table.getColumns().add(priceColumn);


        Random rng = new Random();
        for (int i = 1 ; i <= 20 ; i++) {
            table.getItems().add(new Item("Item "+i, rng.nextInt(1_000_000)));
        }

        Scene scene = new Scene(table);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    private <S,T> TableColumn<S,T> column(String name, Function<S, ObservableValue<T>> property) {
        TableColumn<S,T> column = new TableColumn<>(name);
        column.setCellValueFactory(cellData -> property.apply(cellData.getValue()));
        return column ;
    }

    public static void main(String[] args) {
        launch(args);
    }
}

which produces