在AngularJS中切换数据模型以获得动态选择菜单

Question

我想要做的是有三个不同的<select>菜单,它们都将被绑定到相同的数据中.更改第一个选择菜单,将更改菜单2和3的数据.

这是我的控制器内部:

$scope.data = [
        {
            "id" : "0",
            "site" : "Brands Hatch",
            "buildings" : [
                { "building" : "Building #1" },
                { "building" : "Building #2" },
                { "building" : "Building #3" }
            ],
            "floors" : [
                { "floor" : "Floor #1" },
                { "floor" : "Floor #2" },
                { "floor" : "Floor #3" }
            ]
        },{
            "id" : "1",
            "site" : "Silverstone",
            "buildings" : [
                { "building" : "Building #4" },
                { "building" : "Building #5" },
                { "building" : "Building #6" }
            ],
            "floors" : [
                { "floor" : "Floor #4" },
                { "floor" : "Floor #5" },
                { "floor" : "Floor #6" }
            ]
        }
    ];

这是我到目前为止从参考文献中尝试过的,它使用了我需要的相同想法:http://codepen.io/adnan-i/pen/gLtap

当我从第一个选择菜单中选择"Brands Hatch"或"Silverstone"时,其他两个菜单将更改/更新数据以与正确的数据相对应.我正在使用$ watch来监听我从上面的CodePen链接中获取的更改.

这是观看脚本(未修改,显然不起作用):

$scope.$watch('selected.id', function(id){
        delete $scope.selected.value;
        angular.forEach($scope.data, function(attr){
            if(attr.id === id){
                $scope.selectedAttr = attr;
            }
        });
    });

据我所知,这会删除当前有关更改的数据,然后循环遍历$ scope.data,如果attr.id与传递给函数的id匹配,它会将数据推回到更新视图的范围.我只是坚持构建这个,并希望得到一些指导和帮助,因为我是AngularJS的新手.谢谢!:)

jsFiddle完整的工作,如果有人可以提供帮助:http: //jsfiddle.net/sgdea/

Answer 1

看看我在这里做了什么:http://jsfiddle.net/sgdea/2/

您根本不需要使用$watch- 您只需要为每个相关选择引用输入父项中的选择.

注意ng-options第二个和第三个选择引用selected.site是如何由第一个选择设置的:

<div ng-app="myApp" ng-controller="BookingCtrl">
    <select ng-model="selected.site"
            ng-options="s.site for s in data">
        <option value="">-- Site --</option>
    </select>
    <select ng-model="selected.building"
            ng-options="b.building for b in selected.site.buildings">
        <option value="">-- Building --</option>
    </select>
    <select ng-model="selected.floor"
            ng-options="f.floor for f in selected.site.floors">
        <option value="">-- Floor --</option>
    </select>
</div>

我在javascript中所做的就是删除你的$watch:

var myApp = angular.module( 'myApp', [] );

myApp.controller( 'BookingCtrl', ['$scope', '$location', function ( $scope, $location ) {

    $scope.selected = {};

    $scope.data = [
        {
            "id" : "0",
            "site" : "Brands Hatch",
            "buildings" : [
                { "building" : "Building #1" },
                { "building" : "Building #2" },
                { "building" : "Building #3" }
            ],
            "floors" : [
                { "floor" : "Floor #1" },
                { "floor" : "Floor #2" },
                { "floor" : "Floor #3" }
            ]
        },{
            "id" : "1",
            "site" : "Silverstone",
            "buildings" : [
                { "building" : "Building #4" },
                { "building" : "Building #5" },
                { "building" : "Building #6" }
            ],
            "floors" : [
                { "floor" : "Floor #4" },
                { "floor" : "Floor #5" },
                { "floor" : "Floor #6" }
            ]
        }
    ];
}]);