hasChildrenField : stringDefault: 'hasChildren'

    
 <div id="tree"></div>
 <script>
     var continents, countries, states, tree;
     continents = [
         { id: 1, anyChildren: true, text: 'Asia', type: 'continent' },
         { id: 2, anyChildren: true, text: 'North America', type: 'continent' },
         { id: 3, anyChildren: false, text: 'South America', type: 'continent' }
     ];
     countries = [
         { id: 1, anyChildren: false, continent: 'Asia', text: 'China', type: 'country' },
         { id: 2, anyChildren: false, continent: 'Asia', text: 'Japan', type: 'country' },
         { id: 3, anyChildren: true, continent: 'North America', text: 'USA', type: 'country' },
         { id: 4, anyChildren: false, continent: 'North America', text: 'Canada', type: 'country' }
     ];
     states = [
         { id: 1, country: 'USA', text: 'California', type: 'state' },
         { id: 2, country: 'USA', text: 'Florida', type: 'state' }
     ];
     tree = $('#tree').tree({
         hasChildrenField: 'anyChildren',
         dataSource: continents
     });
     tree.on('expand', function (e, $node, id) {
         var i, children, record = tree.getDataById(id);
         if (tree.getChildren($node).length === 0) {
             if (record.type === 'continent') {
                 children = $.grep(countries, function (i) { return i.continent === record.text; });
                 for (i = 0; i < children.length; i++) {
                     tree.addNode(children[i], $node);
                 }
             } else if (record.type === 'country') {
                 children = $.grep(states, function (i) { return i.country === record.text; });
                 for (i = 0; i < children.length; i++) {
                     tree.addNode(children[i], $node);
                 }
             }
         }
     });
 </script>