如何防止用户表单忽略angularjs ui-bootstrap uib-typeahead中的建议

Question

我正在使用AngularJS v1.6.6和angular-ui-bootstrap版本：2.5.0创建自动完成字段。

一切正常，但是我需要一种方法来确保用户实际上从建议列表中选择了该选项。

这是我的代码：

HTML：

<div class='container-fluid typeahead-demo' ng-controller="TypeaheadCtrl">
<h4>How to prevent user from typing the whole word ignoring suggestions?</h4>
<div>Model: 
<pre>{{selected | json}}</pre>
</div>
<form role="form" name="chooseStateForm" autocomplete="off" novalidate>
    <div class="form-group required">
        <div>
            <label for="state" class="control-label col-sm-3">Choose a State:</label>
                <input type="text" 
                        class="form-control" 
                        required 
                        placeholder="Try typing the whole name of the state ignoring suggestion" 
                        name="state" 
                        ng-model="selected" 
                        uib-typeahead="option as option.name for option in states | filter:{name: $viewValue}" 
                        typeahead-min-length="1" 
                        typeahead-no-results="noresults" 
                        typeahead-show-hint="true" 
                        >
        </div>
        <div ng-if="noresults">
        <p>No match found!</p>
        </div>
    </div>
</form>
<br><br><br><br>
<div>
    <button class="btn btn-primary" type="button" ng-click="$ctrl.ok()" ng-disabled="chooseStateForm.$invalid">OK</button>
    <button class="btn btn-primary" type="button" ng-click="$ctrl.cancel()">Cancel</button>
</div>

JS：

angular.module('app', ['ui.bootstrap']);
angular.module('app').controller('TypeaheadCtrl', function($scope) {

$scope.selected = undefined;
$scope.states = [
{id: 1, name: 'Alabama'},  
{id: 2, name: 'California'}, 
{id: 3, name: 'Delaware'}, 
{id: 4, name: 'Florida'}, 
{id: 5, name: 'Georgia'}, 
{id: 6, name: 'Hawaii'}, 
{id: 7, name: 'Idaho'},  
{id: 8, name: 'Kansas'}, 
{id: 9, name: 'Louisiana'}, 
{id: 10, name: 'Maine'}, 
{id: 11, name: 'Nebraska'}, 
{id: 12, name: 'Ohio'}, 
{id: 13, name: 'Pennsylvania'}, 
{id: 14, name: 'Rhode Island'}, 
{id: 15, name: 'South Carolina'}, 
{id: 16, name: 'Tennessee'},
{id: 17, name: 'Utah'}, 
{id: 18, name: 'Vermont'}, 
{id: 19, name: 'Washington'}
];
});

看到这个jsfiddle，您将理解我的意思： http : //jsfiddle.net/elenat82/yhpbdvva/20/

例如，如果用户希望选择俄亥俄，由于只有4个字母，他会发现只键入“俄亥俄”比选择建议的选项容易。

但是，如果他从建议列表中进行选择，那么我的模型将成为一个字符串，而它却是一个对象。

是的，我在控制器中检查了模型的有效性，但是希望在用户提交表单之前完成模型，我想显示一条错误消息，向用户解释他做错了什么。

----------编辑----------

我找到了实现相同结果的另一种方法，但是使用了指令并扩展了$ validators对象。

这是更新的jsfiddle的链接： http : //jsfiddle.net/elenat82/fL5fw1up/2/

这是更新的代码：

HTML：

<div class='container-fluid typeahead-demo' ng-controller="TypeaheadCtrl">
<h4>How to prevent user from typing the whole word ignoring suggestions?</h4>
<div>Model: 
<pre>{{selected | json}}</pre>
<div>Errors: 
<pre>{{chooseStateForm.state.$error | json}}</pre>
</div>
<form role="form" name="chooseStateForm" autocomplete="off" novalidate>
    <div class="form-group required">
        <div>
            <label for="state" class="control-label col-sm-3">Choose a State:</label>
                <input type="text" 
                        class="form-control" 
                        required 
                        placeholder="Try typing the whole name of the state ignoring suggestion" 
                        name="state" 
                        ng-model="selected" 
                        uib-typeahead="option as option.name for option in states | filter:{name: $viewValue}" 
                        typeahead-min-length="1" 
                        typeahead-no-results="noresults" 
                        typeahead-show-hint="true" 
                        object
                        >
        </div>
        <div ng-if="noresults">
        <p>No match found!</p>
        </div>
    </div>
</form>
<br><br><br><br>
<div>
    <button class="btn btn-primary" type="button" ng-click="$ctrl.ok()" ng-disabled="chooseStateForm.$invalid">OK</button>
    <button class="btn btn-primary" type="button" ng-click="$ctrl.cancel()">Cancel</button>
</div>

JS：

angular.module('app', ['ui.bootstrap']);
angular.module('app').controller('TypeaheadCtrl', function($scope) {

$scope.selected = undefined;
$scope.states = [
{id: 1, name: 'Alabama'},  
{id: 2, name: 'California'}, 
{id: 3, name: 'Delaware'}, 
{id: 4, name: 'Florida'}, 
{id: 5, name: 'Georgia'}, 
{id: 6, name: 'Hawaii'}, 
{id: 7, name: 'Idaho'},  
{id: 8, name: 'Kansas'}, 
{id: 9, name: 'Louisiana'}, 
{id: 10, name: 'Maine'}, 
{id: 11, name: 'Nebraska'}, 
{id: 12, name: 'Ohio'}, 
{id: 13, name: 'Pennsylvania'}, 
{id: 14, name: 'Rhode Island'}, 
{id: 15, name: 'South Carolina'}, 
{id: 16, name: 'Tennessee'},
{id: 17, name: 'Utah'}, 
{id: 18, name: 'Vermont'}, 
{id: 19, name: 'Washington'}
];
});


angular.module('app').directive('object', [function() {
return {
    restrict: 'A',
    scope: {},
    require: 'ngModel',
    link: function (scope, element, attrs, ngModel) {

        ngModel.$validators.object = function(modelValue,viewValue){
            if (angular.isObject(modelValue)) {
                return true;
            }
            else {
                return false;
            }
          };
    }
};

}
]);

Answer 1

您可以为此验证添加方法，例如：

$scope.isSelected = function() {
    return typeof $scope.selected == "object";
}

Answer 2

有一个名为typeahead-editable="false"的属性。 如果将其设置为false，则不允许用户“不”选择某些内容，文本框将设置为空。

链接： https ： //angular-ui.github.io/bootstrap/#！#typeahead

typeahead-editable $（默认值：true）-是否应将模型值限制为仅从弹出窗口中选择的值？

http://jsfiddle.net/yhpbdvva/25/

Answer 3

您将需要遍历数组，并检查所选值（ngModel）在该数组上是否存在。 您可以定义这样的函数并使用ngChange调用它，该函数将在您更改值时运行

<input type="text" 
     class="form-control" 
     required
     name="state" 
     ng-model="selected" 
     .....
     ng-change="testIncluded(selected)">

在控制器内部，执行以下操作（使用Array.prototype.find ）

$scope.testIncluded = function(value) {
    let isSelectedFromStates = $scope.states.find((state) => {
        return state.name === value;
    })
    /// do something ...
}

如果名称存在，则isSelectedFromStates不会是不确定的