public void setTree(final TreeNode<ChartData> TREE) {
        if (null != tree) { getTreeNode().flattened().forEach(node -> node.removeAllTreeNodeEventListeners()); }
        tree.set(TREE);
        getTreeNode().flattened().forEach(node -> node.setOnTreeNodeEvent(e -> redraw()));
        prepareData();
        if (isAutoTextColor()) { adjustTextColors(); }
        drawChart();
    }
Defines the root element of the tree
@param TREE
src/main/java/eu/hansolo/tilesfx/chart/SunburstChart.java