HTML dropdown with ng-options binding does not work with angular-dart -

angular-dart ng-options not seems working.

  <select ng-model="selectedoption" ng-options="s.displaytext s in myoptions">         <option value="">select option</option>     </select> 

<select ng-model="selectedoptionid">         <option value="">select option</option>         <option ng-repeat="o in myoptions" value="{{o.id}}">                     {{o.displaytext}}         </option> </select> 

note selectedoptionid string, if use myoption(type id , displaytext properties) model add new option "?" in html.