<Tree   paddingLeft={20}              // left padding for children nodes in pixels   tree={this.state.tree}        // tree object   onChange={this.handleChange}  // onChange(tree) tree object changed   renderNode={this.renderNode}  // renderNode(node) return react element />  // a sample tree object // node.children, node.collapsed, node.leaf properties are hardcoded {   "module": "react-ui-tree",   "children": [{     "collapsed": true,     "module": "dist",     "children": [{       "module": "node.js"     }]   }] }