我正在使用AngularJS的$http服务来进行Ajax请求。

如何在Ajax请求执行时显示旋转GIF(或另一种类型的忙碌指示器)?

我在AngularJS文档中没有看到类似ajaxstartevent的东西。


当前回答

如果你正在使用ngResource,对象的$resolved属性对加载器很有用:

对于资源,如下所示:

var User = $resource('/user/:id', {id:'@id'});
var user = User.get({id: 1})

你可以将加载器链接到资源对象的$resolved属性:

<div ng-hide="user.$resolved">Loading ...</div>

其他回答

如果你在一个服务/工厂中包装你的api调用,那么你可以跟踪那里的加载计数器(每个答案和@JMaylin的优秀同步建议),并通过一个指令引用加载计数器。或其任何组合。

API 包装器

yourModule
    .factory('yourApi', ['$http', function ($http) {
        var api = {}

        //#region ------------ spinner -------------

        // ajax loading counter
        api._loading = 0;

        /**
         * Toggle check
         */
        api.isOn = function () { return api._loading > 0; }

        /**
         * Based on a configuration setting to ignore the loading spinner, update the loading counter
         * (for multiple ajax calls at one time)
         */
        api.spinner = function(delta, config) {
            // if we haven't been told to ignore the spinner, change the loading counter
            // so we can show/hide the spinner

            if (NG.isUndefined(config.spin) || config.spin) api._loading += delta;

            // don't let runaway triggers break stuff...
            if (api._loading < 0) api._loading = 0;

            console.log('spinner:', api._loading, delta);
        }
        /**
         * Track an ajax load begin, if not specifically disallowed by request configuration
         */
        api.loadBegin = function(config) {
            api.spinner(1, config);
        }
        /**
         * Track an ajax load end, if not specifically disallowed by request configuration
         */
        api.loadEnd = function (config) {
            api.spinner(-1, config);
        }

        //#endregion ------------ spinner -------------

        var baseConfig = {
            method: 'post'
            // don't need to declare `spin` here
        }

        /**
         * $http wrapper to standardize all api calls
         * @param args stuff sent to request
         * @param config $http configuration, such as url, methods, etc
         */
        var callWrapper = function(args, config) {
            var p = angular.extend(baseConfig, config); // override defaults

            // fix for 'get' vs 'post' param attachment
            if (!angular.isUndefined(args)) p[p.method == 'get' ? 'params' : 'data'] = args;

            // trigger the spinner
            api.loadBegin(p);

            // make the call, and turn of the spinner on completion
            // note: may want to use `then`/`catch` instead since `finally` has delayed completion if down-chain returns more promises
            return $http(p)['finally'](function(response) {
                api.loadEnd(response.config);
                return response;
            });
        }

        api.DoSomething = function(args) {
            // yes spinner
            return callWrapper(args, { cache: true });
        }
        api.DoSomethingInBackground = function(args) {
            // no spinner
            return callWrapper(args, { cache: true, spin: false });
        }

        // expose
        return api;
    });

微调控制项指令

(function (NG) {
    var loaderTemplate = '<div class="ui active dimmer" data-ng-show="hasSpinner()"><div class="ui large loader"></div></div>';

    /**
     * Show/Hide spinner with ajax
     */
    function spinnerDirective($compile, api) {
        return {
            restrict: 'EA',
            link: function (scope, element) {
                // listen for api trigger
                scope.hasSpinner = api.isOn;

                // attach spinner html
                var spin = NG.element(loaderTemplate);
                $compile(spin)(scope); // bind+parse
                element.append(spin);
            }
        }
    }

    NG.module('yourModule')
        .directive('yourApiSpinner', ['$compile', 'yourApi', spinnerDirective]);
})(angular);

使用

<div ng-controller="myCtrl" your-api-spinner> ... </div>

下面是我的实现,就像ng-show和请求计数器一样简单。

它使用一个新的服务为所有请求$http:

myApp.service('RqstSrv', [ '$http', '$rootScope', function($http, $rootScope) {
    var rqstService = {};

    rqstService.call = function(conf) {

        $rootScope.currentCalls = !isNaN($rootScope.currentCalls) ?  $rootScope.currentCalls++ : 0;

        $http(conf).then(function APICallSucceed(response) {
            // Handle success
        }, function APICallError(response) {
            // Handle error
        }).then(function() {
            $rootScope.currentCalls--;
        });
    }
} ]);

然后你可以根据当前调用的数量使用你的加载器:

<img data-ng-show="currentCalls > 0" src="images/ajax-loader.gif"/>

分享来自@bulltorious的精彩答案的我的版本,更新到更新的angular构建(我使用了1.5.8版本的代码),还加入了@JMaylin的想法,使用计数器来健壮地处理多个并发请求,以及选择跳过显示小于最小毫秒数的请求动画:

var app = angular.module('myApp');
var BUSY_DELAY = 1000; // Will not show loading graphic until 1000ms have passed and we are still waiting for responses.

app.config(function ($httpProvider) {
  $httpProvider.interceptors.push('busyHttpInterceptor');
})
  .factory('busyHttpInterceptor', ['$q', '$timeout', function ($q, $timeout) {
    var counter = 0;
    return {
      request: function (config) {
        counter += 1;
        $timeout(
          function () {
            if (counter !== 0) {
              angular.element('#busy-overlay').show();
            }
          },
          BUSY_DELAY);
        return config;
      },
      response: function (response) {
        counter -= 1;
        if (counter === 0) {
          angular.element('#busy-overlay').hide();
        }
        return response;
      },
      requestError: function (rejection) {
        counter -= 1;
        if (counter === 0) {
          angular.element('#busy-overlay').hide();
        }
        return rejection;
      },
      responseError: function (rejection) {
        counter -= 1;
        if (counter === 0) {
          angular.element('#busy-overlay').hide();
        }
        return rejection;
      }
    }
  }]);

刚刚发现了angular-busy指令,它显示了一个依赖于某些异步调用的小加载器。

例如,如果你必须创建一个GET,在$作用域中引用承诺,

$scope.req = $http.get('http://google.fr');

像这样称呼它:

<div cg-busy="req"></div>

这是GitHub。

你也可以使用bower安装它(别忘了更新你的项目依赖项):

bower install angular-busy --save

由于position:fixed的功能最近发生了变化,我很难将gif加载器显示在所有元素之上,所以我不得不使用angular内置的jQuery。

Html

<div ng-controller="FetchController">
      <div id="spinner"></div>
</div>

Css

#spinner {display: none}
body.spinnerOn #spinner { /* body tag not necessary actually */
   display: block;
   height: 100%;
   width: 100%;
   background: rgba(207, 13, 48, 0.72) url(img/loader.gif) center center no-repeat;
   position: fixed;
   top: 0;
   left: 0;
   z-index: 9999;
}
body.spinnerOn main.content { position: static;} /* and whatever content needs to be moved below your fixed loader div */

控制器

app.controller('FetchController', ['$scope', '$http', '$templateCache', '$location', '$q',
function($scope, $http, $templateCache, $location, $q) {

angular.element('body').addClass('spinnerOn'); // add Class to body to show spinner

$http.post( // or .get(
    // your data here
})
.then(function (response) {
    console.info('success');     
    angular.element('body').removeClass('spinnerOn'); // hide spinner

    return response.data;               
}, function (response) {                   
    console.info('error'); 
    angular.element('body').removeClass('spinnerOn'); // hide spinner
});

})

希望这对你有所帮助。