angularjs - Angular OpenLayers - Creating a vector layer -

hi guys i'm trying create vector layer using angular-openlayers-directive. keep getting error:

typeerror: cannot set property 'index' of undefined     @ addlayerbeforemarkers ... 

and code i'm using configure map in controller:

 $scope.layers = [       {         name: 'first',         source: {           type: 'imagewms',           url: 'http://mymapserver/blah',           params: {layers: ''}         }       },       {         name: 'features',         source: {           type: 'vector',           source: null //i've tried without option also.         }       }     ]; 

and html:

 <openlayers ol-center="ven" height="100vh">         <ol-layer name="{{layer.name}}" ol-layer-properties="layer" ng-repeat="layer in layers"></ol-layer>  </openlayers> 

why hard vector layer map. want add , remove features later, there isn't sense in using geojson layer, i've seen in examples quite lot.

how can add vector layer map? how can manually add features vector layer? of using angular.