md-not-found 应仅在 md-autocomplete 中的 3 个字符后显示

Question

我正在使用 Angular Material md-autocomplete，因为如果没有建议，我会使用 md-not-found 来显示消息。

我的要求：如果 searchText 的长度小于 3 个字符，如何隐藏 md-not-found。

我尝试了以下代码，但无法修复。请帮助我。

<!DOCTYPE html>
<html>
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/angular_material/1.0.0/angular-material.min.css">
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular-animate.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular-aria.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular-messages.min.js"></script>

<!-- Angular Material Library -->
<script src="http://ajax.googleapis.com/ajax/libs/angular_material/1.0.4/angular-material.min.js"></script>
<body>

<div ng-app="myApp" ng-controller="myCtrl"> 

<p>Country to Select:</p>
<md-content>
<md-autocomplete
          ng-disabled="isDisabled"
          md-no-cache="noCache"
          md-selected-item="selectedItem"
          md-search-text="searchText"
          md-items="item in searchTextChange(searchText)"
          md-item-text="item.country"
          placeholder="Which is your favorite Country?">
        <md-item-template>
          <span md-highlight-text="searchText" md-highlight-flags="^i">{{item.country}}</span>
        </md-item-template>
        <md-not-found>
          No Person matching "{{searchText}}" were found.
        </md-not-found>
      </md-autocomplete>
      </md-content>
      <br/>
</div>

<script>
    var app = angular.module('myApp', ['ngMaterial']);

    app.controller('myCtrl', function ($scope, $http, $q, GetCountryService) {

        $scope.searchText = "";
        $scope.Person = [];
        $scope.selectedItem = [];
        $scope.isDisabled = false;
        $scope.noCache = false;

        $scope.selectedItemChange = function (item) {
            //alert("Item Changed");
        }
        $scope.searchTextChange = function (str) {
   return GetCountryService.getCountry(str);
        }
        
    });
 
 app.factory('GetCountryService', function ($http, $q) {
        return {
            getCountry: function(str) {
                // the $http API is based on the deferred/promise APIs exposed by the $q service
                // so it returns a promise for us by default
    var url = "https://www.bbminfo.com/sample.php?token="+str;
                return $http.get(url)
                    .then(function(response) {
                        if (typeof response.data.records === 'object') {
                            return response.data.records;
                        } else {
                            // invalid response
                            return $q.reject(response.data.records);
                        }

                    }, function(response) {
                        // something went wrong
                        return $q.reject(response.data.records);
                    });
            }
        };
    });
</script>
</body>
</html>

Answer 1

md-min-length 属性缺失

       <md-autocomplete
          ng-disabled="isDisabled"
          md-no-cache="noCache"
          md-min-length="3"
          md-selected-item="selectedItem"
          md-search-text="searchText"
          md-items="item in searchTextChange(searchText)"
          md-item-text="item.country"
          placeholder="Which is your favorite Country?">
        <md-item-template>
          <span md-highlight-text="searchText" md-highlight-flags="^i">{{item.country}}</span>
        </md-item-template>
        <md-not-found>
          No Person matching "{{searchText}}" were found.
        </md-not-found>
      </md-autocomplete>

md-not-found 应仅在 md-autocomplete 中的 3 个字符后显示

md-not-found should be shown only after 3 char in md-autocomplete

angularjs

angularjs-directive

ng-show

ng-hide

angularjs-ng-show