private void addActionButtonColumn(final String name,
                                       final int width) {

        final ActionCell<ContentTemplate> actionCell = new ActionCell<>(this::showActionMenu);

        final Column<ContentTemplate, ContentTemplate> expressionColumn =
                new Column<ContentTemplate, ContentTemplate>(actionCell) {

                    @Override
                    public ContentTemplate getValue(final ContentTemplate row) {
                        return row;
                    }

                    @Override
                    public void onBrowserEvent(final Context context,
                                               final Element elem,
                                               final ContentTemplate rule,
                                               final NativeEvent event) {
                        super.onBrowserEvent(context, elem, rule, event);
//                        GWT.log("Rule " + rule.getRuleNumber() + " clicked, event " + event.getType());
                    }
                };
        dataGrid.addResizableColumn(expressionColumn, name, width);
    }
Add the columns to the table.
stroom-core-client/src/main/java/stroom/receive/content/client/presenter/ContentTemplateListPresenter.java