[{
  "id": 1,
  "text": "Root node",
  "icon":"wb-folder",
  "state":{
    "opened":true
  },
  "children": [{
    "id": 2,
    "text": "Child node 1",
    "icon":"wb-folder"
  }, {
    "id": 3,
    "text": "Child node 2",
    "icon":"wb-folder"
  }]
}]