Issue with AngularJS Dropdown

问题

I have created AngularJS dependable dropdowns, its working fine with static data from script file. Now how can I bind data to these dropdowns from an URL. I don't have a separate url for dropdowns, there is one url delivering everything.

How should I parse the data to get the required output? Iam very new to this, Will be grateful if anyone can help!!

回答1:

First working Punker here:

http://plnkr.co/edit/okKOeQViflRseqrOYeOY?p=preview

The problem is your question states something and your demo shows something else.

You can directly parse the JSON data on fly using angular then you don't have ng-change function to detect which dropdown was selected. Refer to the below code on how I'm parsing the data in html itself.

                <div class="col-sm-4">
                    <am-multiselect class="input-lg"
                                    template-url="multiselect.tmpl.html"
                                    ng-model="selectedcountry" ms-header="Select country" style="width:200px;"
                                    options="c.CountryName for c in table"
                                    ng-change="setState(selectedcountry)"
                                    change="selected()"></am-multiselect>



                </div>
            </div>
            <div class="form-group">

                <div class="col-sm-4">
                    <am-multiselect class="input-lg" multiple="true" ms-selected="{{selectedState.length}} State(s) selected"
                                    ng-model="selectedState" ms-header="Select States"
                                    options="s.STATE for s in table"
                                    ng-change="setCity(selectedState)"
                                    template-url="multiselect.tmpl.html" style="width:500px;"
                                    change="selected()">
                    </am-multiselect>

                </div>
            </div>

            <div class="form-group">

                <div class="col-sm-4">
                    <am-multiselect class="input-lg" multiple="true" ms-selected="{{selectedCity.length}} City(ies) selected"
                                    ng-model="selectedCity" ms-header="Select City"
                                    options="m.CityName for m in table"
                                    template-url="multiselect.tmpl.html" style="width:500px;"
                                    change="selected()"></am-multiselect>

                </div>
            </div>

next your second dropdown which is STATE doesn't trigger on change even if the scope is changed.

So use a $watch to see the changes to scope when it happens apply it to the CITY

So your js:

angular.module('app', ['am.multiselect']);

angular.module('app')
  .controller('ctrl', function($scope, $http, $location, $filter,$window) {

    var tableData = {
      "Table": [{
        "CountryUid": 3,
        "CountryName": "INDIA",
        "STATE": "AndraPradesh",
        "CityId": 3,
        "CityName": "Vijayawada"
      }, {
        "CountryUid": 2,
        "CountryName": "USA",
        "STATE": "Florida",
        "CityId": 3,
        "CityName": "Tampa"
      }, {
        "CountryUid": 3,
        "CountryName": "INDIA",
        "STATE": "Assam",
        "CityId": 3,
        "CityName": "Jorhat"
      }]
    };

    var countries = [];
    var states = [];
    var cities = [];

    $scope.table = tableData.Table;
    $scope.countries = countries;
    $scope.states = states;
    $scope.cities = cities;
    $scope.selectedsite = null;
    $scope.selectedState = [];
    $scope.selectedCity = [];

    $scope.setState = function(country) {
      $scope.selectedStates = tableData.Table.filter(function(el) {
        return el.CountryName === country
      });
      $scope.selectedState = $scope.selectedStates.map(function(elm) {return elm.STATE;});
    }
    $scope.setCity = function(state) {
      selectedCity = tableData.Table.filter(function(el) {
        return el.STATE === state
      });
      $scope.selectedCity = selectedCity.map(function(elm) {return elm.CityName;});
    }
    $scope.$watch('selectedStates', function(newVal, oldVal, theScope) {
      $scope.selectedCity = newVal.map(function(elm) {return elm.CityName;});
      console.log(newVal,$scope.selectedCity);
    });

PS: The above plunker isn't very perfect you may some some minor issues which you should be able to solve.

来源：https://stackoverflow.com/questions/37018619/issue-with-angularjs-dropdown