<zk xmlns:n="native">

    <style>

        .z-icon-folder {

          /*color: rgb(0, 60, 150);*/

          color: rgb(250, 180, 20);

        }

    </style>

    <tree hflex="true" vflex="true">

        <treechildren>

            <treeitem>

                <treerow>

                  <treecell label='This is a tree!!' />

                </treerow>

                <treechildren>

                    <treeitem>

                        <treerow>

                            <treecell label="Subnode 1" iconSclass="z-icon-folder"/>

                        </treerow>

                    </treeitem>

                    <treeitem>

                        <treerow>

                            <treecell label="Subnode 2"/>

                        </treerow>

                    </treeitem>

                    <treeitem>

                        <treerow>

                            <treecell label="Subnode 3"/>

                        </treerow>

                    </treeitem>

                </treechildren>

            </treeitem>

        </treechildren>

    </tree>

</zk>

​