public VTreeTableGeneratedRow(UIDL uidl, char[] aligns) {
                super(uidl, aligns);
                addStyleName("v-table-generated-row");
            }

            public boolean isSpanColumns() {
                return spanColumns;
            }

            @Override
            protected void initCellWidths() {
                if (spanColumns) {
                    setSpannedColumnWidthAfterDOMFullyInited();
                } else {
                    super.initCellWidths();
                }
            }

            private void setSpannedColumnWidthAfterDOMFullyInited() {
                // Defer setting width on spanned columns to make sure that
                // they are added to the DOM before trying to calculate
                // widths.
                Scheduler.get().scheduleDeferred(new ScheduledCommand() {

                    @Override
                    public void execute() {
                        if (showRowHeaders) {
                            setCellWidth(0, tHead.getHeaderCell(0)
                                    .getWidthWithIndent());
                            calcAndSetSpanWidthOnCell(1);
                        } else {
                            calcAndSetSpanWidthOnCell(0);
                        }
                    }
                });
            }

            @Override
            protected boolean isRenderHtmlInCells() {
                return htmlContentAllowed;
            }

            @Override
            protected void addCellsFromUIDL(UIDL uidl, char[] aligns, int col,
                    int visibleColumnIndex) {
                htmlContentAllowed = uidl.getBooleanAttribute("gen_html");
                spanColumns = uidl.getBooleanAttribute("gen_span");

                final Iterator<?> cells = uidl.getChildIterator();
                if (spanColumns) {
                    int colCount = uidl.getChildCount();
                    if (cells.hasNext()) {
                        final Object cell = cells.next();
                        if (cell instanceof String) {
                            addSpannedCell(uidl, cell.toString(), aligns[0],
                                    "", htmlContentAllowed, false, null,
                                    colCount);
                        } else {
                            addSpannedCell(uidl, (Widget) cell, aligns[0], "",
                                    false, colCount);
                        }
                    }
                } else {
                    super.addCellsFromUIDL(uidl, aligns, col,
                            visibleColumnIndex);
                }
            }

            private void addSpannedCell(UIDL rowUidl, Widget w, char align,
                    String style, boolean sorted, int colCount) {
                TableCellElement td = DOM.createTD().cast();
                td.setColSpan(colCount);
                initCellWithWidget(w, align, style, sorted, td);

        setCacheRate(4);
    }

    @Override
    protected String formatPropertyValue(Object rowId, Object colId, Property<?> property) {
        String result = super.formatPropertyValue(rowId, colId, property);
        return StringEscapeUtils.escapeHtml(result);
    }

    @Override
    public void changeVariables(Object source, Map<String, Object> variables) {
        super.changeVariables(source, variables);
        if (variables.containsKey("selectAll")) {
            boolean selectAll = (Boolean) variables.get("selectAll");
            if (selectAll) {
                Collection<?> ids = getItemIds();
                for (final Object id : ids) {
                    select(id);
                }
            } else {
                setValue(null);
            }
        }

        if (variables.containsKey("toggleSelection")) {
            boolean selected = (Boolean) variables.get("toggleSelection");
            String key = String.valueOf(variables.get("toggledRowId"));
            final Object id = itemIdMapper.get(key);
            if (selected) {
                select(id);
            } else {
                unselect(id);
            }
        }
    }

                addTreeSpacer(rowUidl);
            }

            @Override
            protected void setCellWidth(int cellIx, int width) {
                if (isSpanColumns()) {
                    if (showRowHeaders) {
                        if (cellIx == 0) {
                            super.setCellWidth(0, width);
                        } else {
                            // We need to recalculate the spanning TDs width for
                            // every cellIx in order to support column resizing.
                            calcAndSetSpanWidthOnCell(1);
                        }
                    } else {
                        // Same as above.
                        calcAndSetSpanWidthOnCell(0);
                    }
                } else {
                    super.setCellWidth(cellIx, width);
                }
            }

            private void calcAndSetSpanWidthOnCell(final int cellIx) {
                int spanWidth = 0;
                for (int ix = (showRowHeaders ? 1 : 0); ix < tHead
                        .getVisibleCellCount(); ix++) {
                    spanWidth += tHead.getHeaderCell(ix).getOffsetWidth();
                }
                Util.setWidthExcludingPaddingAndBorder((Element) getElement()
                        .getChild(cellIx), spanWidth, 13, false);
            }
        }

        public void setFooterCell(int index, FooterCell cell) {
            if (cell.isEnabled()) {
                // we're moving the cell
                DOM.removeChild(tr, cell.getElement());
                orphan(cell);
                visibleCells.remove(cell);
            }
            if (index < visibleCells.size()) {
                // insert to right slot
                DOM.insertChild(tr, cell.getElement(), index);
                adopt(cell);
                visibleCells.add(index, cell);
            } else if (index == visibleCells.size()) {
                // simply append
                DOM.appendChild(tr, cell.getElement());
                adopt(cell);
                visibleCells.add(cell);
            } else {
                throw new RuntimeException(
                        "Header cells must be appended in order");
            }
        }

        /**
         * Remove a cell by using the columnId
         * 
         * @param colKey
         *            The columnId to remove
         */
        public void removeCell(String colKey) {