TableView doesn't commit values on focus lost event

Question

I\'d like to create a table with the following features:

• Edit on key press
• Enter key = next row
• Tab key = next column
• Escape key = c

Answer 1

My proposal to solve this atrocity is the following (sorry for missing JavaDoc).

This is a cancel-to-commit redirection solution. I tested it under LINUX with Java 1.8.0-121. Here, the only way how to discard a cell editor is to press ESCAPE.

import javafx.beans.binding.Bindings;
import javafx.scene.Node;
import javafx.scene.control.ContentDisplay;
import javafx.scene.control.TableCell;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;

public abstract class AutoCommitTableCell extends TableCell
{
    private Node field;
    private boolean startEditing;
    private T defaultValue;


    /** @return a newly created input field. */
    protected abstract Node newInputField();

    /** @return the current value of the input field. */
    protected abstract T getInputValue();

    /** Sets given value to the input field. */
    protected abstract void setInputValue(T value);

    /** @return the default in case item is null, must be never null, else cell will not be editable. */
    protected abstract T getDefaultValue();

    /** @return converts the given value to a string, being the cell-renderer representation. */
    protected abstract String inputValueToText(T value);


    @Override
    public void startEdit() {
        try {
            startEditing = true;

            super.startEdit();  // updateItem() will be called

            setInputValue(getItem());
        }
        finally {
            startEditing = false;
        }
    }

    /** Redirects to commitEdit(). Leaving the cell should commit, just ESCAPE should cancel. */
    @Override
    public void cancelEdit() {
        // avoid JavaFX NullPointerException when calling commitEdit()
        getTableView().edit(getIndex(), getTableColumn());

        commitEdit(getInputValue());
    }

    private void cancelOnEscape() {
        if (defaultValue != null)    {   // canceling default means writing null
            setItem(defaultValue = null);
            setText(null);
            setInputValue(null);
        }
        super.cancelEdit();
    }

    @Override
    protected void updateItem(T newValue, boolean empty) {
        if (startEditing && newValue == null)
            newValue = (defaultValue = getDefaultValue());

        super.updateItem(newValue, empty);

        if (empty || newValue == null) {
            setText(null);
            setGraphic(null);
        }
        else {
            setText(inputValueToText(newValue));
            setGraphic(startEditing || isEditing() ? getInputField() : null);
        }
    }

    protected final Node getInputField()    {
        if (field == null)    {
            field = newInputField();

            // a cell-editor won't be committed or canceled automatically by JFX
            field.addEventFilter(KeyEvent.KEY_PRESSED, event -> {
                if (event.getCode() == KeyCode.ENTER || event.getCode() == KeyCode.TAB)
                    commitEdit(getInputValue());
                else if (event.getCode() == KeyCode.ESCAPE)
                    cancelOnEscape();
            });

            contentDisplayProperty().bind(
                    Bindings.when(editingProperty())
                        .then(ContentDisplay.GRAPHIC_ONLY)
                        .otherwise(ContentDisplay.TEXT_ONLY)
                );
        }
        return field;
    }
}

You can extend this class to support any data type.

Example for a String field is (Person is an example bean):

import javafx.scene.Node;
import javafx.scene.control.TextField;
import jfx.examples.tablebinding.PersonsModel.Person;

public class StringTableCell extends AutoCommitTableCell
{
    @Override
    protected String getInputValue() {
        return ((TextField) getInputField()).getText();
    }

    @Override
    protected void setInputValue(String value) {
        ((TextField) getInputField()).setText(value);
    }

    @Override
    protected String getDefaultValue() {
        return "";
    }

    @Override
    protected Node newInputField() {
        return new TextField();
    }

   @Override
    protected String inputValueToText(String newValue) {
        return newValue;
    }
}

To be applied in this way:

final TableColumn nameColumn = new TableColumn("Name");
nameColumn.setCellValueFactory(
        cellDataFeatures -> cellDataFeatures.getValue().nameProperty());
nameColumn.setCellFactory(
        cellDataFeatures -> new StringTableCell());