Question

我正在关注承诺的this Angular教程。我有一个检查数组是否为空的服务，如果是，则命中REST服务，返回一个promise并更新数组。这是相关代码：

  requestingProviders: [],
  getRequestingProviders: function() {
    var that = this;
    var deferred = $q.defer();
    if(this.requestingProviders.length === 0) {
      this.getResource().search({
        role: 'REQUESTING_PROVIDER'
      }, function(data) {
        that.requestingProviders = data.providers;
        deferred.resolve(data.providers);
      });
      return deferred.promise;
    } else {
      return that.requestingProviders;
    }
  }

service正在调用controller。以下是调用它的代码：

$scope.providers = providerService.getRequestingProviders();

进行REST调用并返回正常，但视图永远不会更新。这不像教程解释的那样工作。 Here是一个能够展示我期待的东西。我做错了什么？

Answer 1

你需要解决你的承诺：

var prom = providerService.getRequestingProviders();

prom.then(function (data) {
   $scope.providers = data;
});

此外，将代码更改为始终返回承诺：

getRequestingProviders: function() {
    var that = this;
    var deferred = $q.defer();
    if(this.requestingProviders.length === 0) {
      this.getResource().search({
        role: 'REQUESTING_PROVIDER'
      }, function(data) {
        that.requestingProviders = data.providers;
        deferred.resolve(data.providers);
      });

    } else {
      deferred.resolve(that.requestingProviders);
    }
    return deferred.promise;
  }

$ G在GET请求返回时不更新

1 个答案: