typeahead控件的上/下箭头键问题（angular customize-typeahead-widget）+没有bootstrap

Question

我们创建了pluncker：http://plnkr.co/edit/dgjHsKQLVPpacfGpQCUQ?p=preview，我们已经实现了typeahead控件。

问题在步骤中解释： -

1. 键入“a”之类的内容以获取typeahead中的数据（列表将是 填充）
2. 按向下箭头键（焦点应在列表项上）
3. 按向下箭头键，它应该向下和向下按，然后按向上键 应该列出。

但我们无法使用上下键遍历列表。

angular.module('autosearch', []);
angular.module('autosearch').controller('TypeaheadCtrl', function($scope, $http) {
  $scope.search= {}
 console.log('hiiii');
}).directive('searchItems', ['$document', function($document) {
    return {
      restrict: 'E',
      scope: {
        search: '=ngModel'
      },
      templateUrl: 'auto-search.html',
      link: function(scope, elem, attr) {
        console.log('fghfgh');
        scope.product = {};
        scope.quantity = 10;
        scope.categoryQuantity = 7;
        scope.setCurrent = function(product) {
          return scope.categories = product.category;
        };
        scope.search.searchItems = function() {
          scope.showList = true;
          scope.items = [
            {
              "id": "99",
              "name": "Apricot Kernels",
              "category": []
            }, {
              "id": "136",
              "name": "Apparel",
              "category": [
                {
                  "name": "Coats",
                  "id": 156
                }, {
                  "name": "Dresses",
                  "id": 157
                }, {
                  "name": "Ethnic Clothing",
                  "id": 165
                }, {
                {
                  "name": "Mannequins",
                  "id": 224
                }, {
                  "name": "Maternity Clothing",
                  "id": 225
                }, {
                  "name": "Men's Shirts",
                  "id": 226
                }, {
                  "name": "Other Apparel",
                  "id": 227
                }, {
                  "name": "Pants \u0026 Trousers",
                  "id": 228
                },{
                  "name": "Wedding Apparel \u0026 Accessories",
                  "id": 296
                }, {
                  "name": "Work Wear",
                  "id": 302
                }
              ]
            }, {
              "id": "139",
              "name": "Apparel Stock",
              "category": []
            }, {
              "id": "1999",
              "name": "Apparel Accessories Machinery",
              "category": [
                {
                  "name": "Cap Making Machinery",
                  "id": 2000
                }, {
                  "name": "Gloves Making Machinery",
                  "id": 2001
                }, {
                , {
                  "name": "Sock Knitting Machinery",
                  "id": 2005
                }
              ]
            }, {
              "id": "138",
              "name": "Apparel Processing Services",
              "category": []
            }, {
              "id": "1990",
              "name": "Apparel \u0026 Textile Machinery Parts",
              "category": [
                {
                  "name": "Apparel Machinery Parts",
                  "id": 1991
                }, {
                {
                  "name": "Sock Knitting Machinery Parts",
                  "id": 1997
                }, {
                  "name": "Textile Machinery Parts",
                  "id": 1998
                }
              ]
            }, {
              "id": "1990",
              "name": "Parts",
              "category": [
                {
                  "name": "Apparel Machinery Parts",
                  "id": 1991
                }, {
                  "name": "Cap Making Machinery Parts",
                  "id": 1992
                }, {
                  "name": "Glove Making Machinery Parts",
                  "id": 1993
                }, {
                  "name": "Sock Knitting Machinery Parts",
                  "id": 1997
                }, {
                  "name": "Textile Machinery Parts",
                  "id": 1998
                }
              ]
            }, {
              "id": "1990",
              "name": "Machinery Parts",
              "category": [
                {
                  "name": "Apparel Machinery Parts",
                  "id": 1991
                }, {
                  "name": "Cap Making Machinery Parts",
                  "id": 1992
                }, {
                  "name": "Glove Making Machinery Parts",
                  "id": 1993
                , {
                  "name": "Sock Knitting Machinery Parts",
                  "id": 1997
                }, {
                  "name": "Textile Machinery Parts",
                  "id": 1998
                }
              ]
            }, {
              "id": "1990",
              "name": "Textile Machinery Parts",
              "category": [
                {
                  "name": "Machinery Parts",
                  "id": 1991
                }, {
                  "name": "Cap Making Machinery Parts",
                  "id": 1992
                }, {
                  "name": "Glove Making Machinery Parts",
                  "id": 1993
                }, {
                  "name": "Home Textile Product Machinery Parts",
                  "id": 1994
                }, {
                  "name": "Leather Production Machinery Parts",
                  "id": 1995
                }, {
                  "name": "Shoemaking Machinery Parts",
                  "id": 1996
                }, {
                  "name": "Sock Knitting Machinery Parts",
                  "id": 1997
                }, {
                  "name": "Textile Machinery Parts",
                  "id": 1998
                }
              ]
            }, {
              "id": "136",
              "name": "Apparel",
              "category": [
                {
                  "name": "Apparel Design Services",
                  "id": 137
                }, {
                  "name": "Apparel Processing Services",
                  "id": 138
                , {
                  "name": "Garment Accessories",
                  "id": 171
                }, {
                  "name": "Hoodies \u0026 Sweatshirts",
                  "id": 198
                }, {
                  "name": "Hosiery",
                  "id": 199
                }, {
                  "name": "Infant \u0026 Toddlers Clothing",
                  "id": 205
                }, {
                  "name": "Jackets",
                  "id": 221
                }, {
                  "name": "Jeans",
                  "id": 222
                }, {
                  "name": "Ladies Blouses \u0026 Tops",
                  "id": 223
                }, {
                  "name": "Mannequins",
                  "id": 224
                }, {
                  "name": "Maternity Clothing",
                  "id": 225
                }, {
                  "name": "Men's Shirts",
                  "id": 226
                }, {
                  "name": "Other Apparel",
                  "id": 227
                }, {
                  "name": "Pants \u0026 Trousers",
                  "id": 228
                }, {
                  "name": "Sewing Supplies",
                  "id": 229
                }, {
                  "name": "Shorts",
                  "id": 234
                }, {
                  "name": "Skirts",
                  "id": 235
                }, {
                  "name": "Sleepwear",
                  "id": 236
                }, {
                  "name": "Sportswear",
                {
                  "name": "Used Clothes",
                  "id": 294
                }, {
                  "name": "Vests \u0026 Waistcoats",
                  "id": 295
                }, {
                  "name": "Wedding Apparel \u0026 Accessories",
                  "id": 296
                }, {
                  "name": "Work Wear",
                  "id": 302
                }
              ]
            }
          ];
          console.log(scope.items, 'itwe,sss');
        };
      }
    }
  }]);