how to use ng-required in ngJsTree?

[michimau]

"myObj.$error.required" in never raised. Any hint?

i.e.:

<div js-tree="treeConfig" name="table1_Sectors" id="table1_Sectors" should-apply="ac()" ng-click="blurr($event)" tree="sectorsTreeInstance" ng-model="sectorsData" tree-events="changed:nodeSectorChanged;ready:readyCB"></div>
                                    <div class="invalid-wrap" ng-show="ValidationEnabled && Table1.table1_Sectors.$error.required"><span translate="Labels.Validation.empty"></span></div>