javascript - how to enable disable dropdown based on the previous selected dropdown using angular js? -

i have dropdown made ng-repeat have disable dropdowns based on condition eg: dropdown process should selected dropdown worktype should enabled:

here html :

<div class="subcellcreator" id="value">     <div ng-show="l.text" class="textbox">         <input type="text" ng-model="l.model" class="casetext" ng-click="check()" />     </div>     <div ng-show="l.dropdown" class="styled-select">         <select ng-model="l.model" ng-options="opt opt in l.options" ng-click="check()" ng-change="changevalue(l.model,l.name)" class="caseselect" ng-disabled="checkdependent()">             <option value=""></option>         </select>         <div class="select-button">             <div class="small-arrow-down"></div>         </div>     </div> </div> 

here controller :

var actorid;         $scope.changevalue = function(value, name) {             var index;             var field;             $scope.errorshow = false;             // console.log("value: " + value + " name  " + name);             // console.log("inside changevalue");             var postdependent = appconfig.mandatefields[name].dependent;             if (postdependent != 'nil') {                  // console.log("in post dependent: " + postdependent);                 (i = 0; < $scope.fields.length; i++) {                     if ($scope.fields[i].field == postdependent) {                         index = i;                         field = $scope.fields[i].name;                     }                 }                 // console.log("index :" + index + "  field :" + field);             }             if (name == "work type") {                  // console.log("value : " + value);                 $scope.fields[8].options = fielddependent[value];             }              if (name == "approver") {                  // console.log("inside approver change");                 (i = 0; < approverlist.name.length; i++) {                     if (value == approverlist.name[i]) {                         actorid = approverlist.id[i];                     }                 }                  // console.log("actor id : " + actorid);              }         } 

how apply ng-disabled various conditions ?