Question

我正在创建一个搜索页面，用户可以使用第一个下拉列表中列出的预先选择的搜索条件搜索数据。在下面的示例中，这些标准是“名字”，“国家”和“国籍”。

当用户选择国家/地区或国籍时，会出现第二个下拉列表，选择其中一个国家/地区。要填充此下拉列表，请使用ng-options，其中包含一个指向控制器中定义的字符串的变量。

但是当选择了这两个选项中的一个并且您想切换到另一个时，第二个下拉列表不会更新。 ngOptions中的值确实在HTML中更新，只是下拉列表中的数据不是。

当您在中间选择“名字”时，没有问题。有谁知道我可以使用什么，所以第二个下拉列表中的值会更新？

以下是我的代码和工作人员：http://plnkr.co/edit/LYpOdoLpgiMeHxlGzmub?p=preview

var myApp = angular.module('myApp', []);
myApp.controller("SomeController", function($scope) {
  
    var vm = this;
    
    vm.search = {id:0, criteria: {}, value: ''};
    
    vm.referenceData = {
      countries: [
        {COUNTRY_ID:1, COUNTRY_NAME: 'UNITED KINGDOM'},
        {COUNTRY_ID:2, COUNTRY_NAME: 'AUSTRALIA'},
        {COUNTRY_ID:3, COUNTRY_NAME: 'SOUTH AFRICA'},
        {COUNTRY_ID:4, COUNTRY_NAME: 'NETHERLANDS'},  
      ],
      nationalities: [
        {NATIONALITY_ID: 1, NATIONALITY_NAME: "BRITISH"},
        {NATIONALITY_ID: 2, NATIONALITY_NAME: "AUSTRALIAN"},
        {NATIONALITY_ID: 3, NATIONALITY_NAME: "SOUTH AFRICAN"},
        {NATIONALITY_ID: 4, NATIONALITY_NAME: "DUTCH"},  
        ]
    };
    
    vm.criteriaList = [
        { name: 'First Name', key: 'FIRST_NAME'},
        { name: 'Country', key: 'COUNTRY_ID', options:'o.COUNTRY_ID as o.COUNTRY_NAME for o in ctrl.referenceData.countries' },
        { name: 'Nationality', key: 'NATIONALITY', options:'o.NATIONALITY_ID as o.NATIONALITY_NAME for o in ctrl.referenceData.nationalities' }
    ];
});

<!DOCTYPE html>
<html>

<head>
  <script data-require="angular.js@1.6.2" data-semver="1.6.2" src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.2/angular.js"></script>
  <link rel="stylesheet" href="style.css" />
  <script src="script.js"></script>
</head>

<body ng-app="myApp" ng-controller="SomeController as ctrl">


  <p>Criteria:</p>
  <select ng-model="search.criteria" ng-change="search.value = ''" ng-options="criteria as criteria.name for criteria in ctrl.criteriaList">
    <option value="">- Select Criteria -</option>
  </select>
  
  
  <p>Value:</p>
  <!-- TEXT INPUT -->
  <input type="text" ng-model="search.value" placeholder="Search Value" ng-if="!search.criteria.options" />
  <!-- DROPDOWN INPUT -->
  <select ng-model="search.value" ng-if="search.criteria.options" ng-options="{{search.criteria.options}}"></select>

</html>

Answer 1

这是一个简单的修复，您只需要一个变量，如果每次切换时都可以输出第二个下拉列表。由于没有scope.$apply发生，所以dom需要强制刷新的东西。

Plunker Working

试试这个：

var myApp = angular.module('myApp', []);
myApp.controller("SomeController", function($scope, $timeout) {

    var vm = this;
    vm.somVal = false; ///ADD THIS
    vm.search = {id:0, criteria: {}, value: ''};

    vm.triggerSomeVal = function(){ ///ADD THIS
      vm.someVal = true;
      $timeout(function(){vm.someVal = false}, 100)
    };

    vm.referenceData = {
      countries: [
        {COUNTRY_ID:1, COUNTRY_NAME: 'UNITED KINGDOM'},
        {COUNTRY_ID:2, COUNTRY_NAME: 'AUSTRALIA'},
        {COUNTRY_ID:3, COUNTRY_NAME: 'SOUTH AFRICA'},
        {COUNTRY_ID:4, COUNTRY_NAME: 'NETHERLANDS'},  
      ],
      nationalities: [
        {NATIONALITY_ID: 1, NATIONALITY_NAME: "BRITISH"},
        {NATIONALITY_ID: 2, NATIONALITY_NAME: "AUSTRALIAN"},
        {NATIONALITY_ID: 3, NATIONALITY_NAME: "SOUTH AFRICAN"},
        {NATIONALITY_ID: 4, NATIONALITY_NAME: "DUTCH"},  
        ]
    };

    vm.criteriaList = [
        { name: 'First Name', key: 'FIRST_NAME'},
        { name: 'Country', key: 'COUNTRY_ID', options:'o.COUNTRY_ID as o.COUNTRY_NAME for o in ctrl.referenceData.countries' },
        { name: 'Nationality', key: 'NATIONALITY', options:'o.NATIONALITY_ID as o.NATIONALITY_NAME for o in ctrl.referenceData.nationalities' }
    ];
});

<p>Criteria:</p>
  <select ng-model="search.criteria" ng-change="search.value = ''; ctrl.triggerSomeVal()" ng-options="criteria as criteria.name for criteria in ctrl.criteriaList">
    <option value="">- Select Criteria -</option>
  </select>


  <p>Value:</p>
  <!-- TEXT INPUT -->
  <input type="text" ng-model="search.value" placeholder="Search Value" ng-if="!search.criteria.options" />
  <!-- DROPDOWN INPUT ADD !someVal-->
  <select ng-model="search.value" ng-if="search.criteria.options && !ctrl.someVal" ng-options="{{search.criteria.options}}"></select>

第一个下拉列表更改时，AngularJS第二个下拉列表不会更新

1 个答案: