GWT: event handling in a composite cell

CompositeCell allows you to customize the contents of a table cell in GWT using Java. We can put almost any other group of widgets in a table cell and arrange them as needed. The problem is that if we used html tags to define the CompositeCell layout as another table (see the description of the anonymous CompositeCell class below), we lose event processing for the cell components: (.

Running the following code, when we click the buttons in the cell, implements a pop-up window in response to the processing of the event IF WE COMMENT an anonymous implementation of CompositeCell.

I debugged CompositeCell.onBrowserEvent (Context, Element, C, NativeEvent, ValueUpdater) because I believe that defining cell layout using HTML table tags breaks the chain of events in the GWT widget hierarchy, but has failed so far.

Note: both commented and unformed versions of the code implement the same graphical interface. This example simply intends to show that we lose event processing when customizing the contents of a cell.

public class ActionCellTest implements EntryPoint {

    private static final String SERVER_ERROR = "An error occurred while " + "attempting to contact the server. Please check your network "
            + "connection and try again.";

    private final GreetingServiceAsync greetingService = GWT.create(GreetingService.class);

    public void onModuleLoad() {
        CellTable<Person> table = new CellTable<ActionCellTest.Person>();

        final List<HasCell<Person, ?>> cells = new LinkedList<HasCell<Person, ?>>();
        cells.add(new HasCellImpl("first name", new ActionCell.Delegate<Person>() {

            @Override
            public void execute(Person object) {
                Window.alert(object.getFirstName());
            }
        }));
        cells.add(new HasCellImpl("last name", new ActionCell.Delegate<ActionCellTest.Person>() {

            @Override
            public void execute(Person object) {
                Window.alert(object.getLastName());
            }
        }));

        CompositeCell<Person> cell = new CompositeCell<Person>(cells) {

            @Override
            public void render(Context context, Person value, SafeHtmlBuilder sb) {
                sb.appendHtmlConstant("<table><tbody><tr>");
                for (HasCell<Person, ?> hasCell : cells) {
                    render(context, value, sb, hasCell);
                }
                sb.appendHtmlConstant("</tr></tbody></table>");
            }

            @Override
            protected <X> void render(Context context, Person value, SafeHtmlBuilder sb, HasCell<Person, X> hasCell) {
                Cell<X> cell = hasCell.getCell();
                sb.appendHtmlConstant("<td>");
                cell.render(context, hasCell.getValue(value), sb);
                sb.appendHtmlConstant("</td>");
            }

            @Override
            protected Element getContainerElement(Element parent) {
                return parent.getFirstChildElement().getFirstChildElement().getFirstChildElement();
            }

        };
        table.addColumn(new TextColumn<ActionCellTest.Person>() {

            @Override
            public String getValue(ActionCellTest.Person object) {
                return object.getFirstName() + " " + object.getLastName();
            }
        }, "name");

        table.addColumn(new Column<Person, Person>(cell) {

            @Override
            public Person getValue(ActionCellTest.Person object) {
                return object;
            }
        }, "composite");

        LinkedList<Person> data = new LinkedList<ActionCellTest.Person>();
        data.add(new Person("Amy", "Reed"));
        data.add(new Person("Tim", "Gardner"));
        table.setRowData(data);

        RootPanel.get().add(table);
    }

    private class HasCellImpl implements HasCell<Person, Person> {
        private ActionCell<Person> fCell;

        public HasCellImpl(String text, Delegate<Person> delegate) {
            fCell = new ActionCell<Person>(text, delegate);
        }

        @Override
        public Cell<Person> getCell() {
            return fCell;
        }

        @Override
        public FieldUpdater<Person, Person> getFieldUpdater() {
            return null;
        }

        @Override
        public Person getValue(Person object) {
            return object;
        }
    }

    private class Person {
        private String fFirstName;
        private String fLastName;

        public Person(String first, String last) {
            fFirstName = first;
            fLastName = last;
        }

        public String getFirstName() {
            return fFirstName;
        }

        public String getLastName() {
            return fLastName;
        }
    }
}