Sencha 似乎不喜欢 Rails' json

Question

我有一个 Rails 控制器，它将一些模型渲染为 json。

 @events = Event.all
 respond_to do |format|
  format.html # index.html.erb
  format.xml  { render :xml => @events }
  format.json { render :json => { :results => @events } }
 end

输出如下所示：

{
    "results":
    [
        {
            "name":"test",
            "created_at":"2011-03-23T13:32:57Z",
            "latitude":60.0,
            "location":null,
            "updated_at":"2011-04-14T16:38:54Z",
            "id":1,
            "longitude":30.0,
            "takes_place_at":"2011-03-23T13:32:00Z"
        },
        {
            "name":"x",
            "created_at":"2011-03-23T13:36:44Z",
            "latitude":60.0,
            "location":null,
            "updated_at":"2011-03-23T13:36:44Z",
            "id":2,
            "longitude":30.0,
            "takes_place_at":"2011-03-23T13:36:00Z"
        },
        {
            "name":"Gruempi",
            "created_at":"2011-03-24T14:00:32Z",
            "latitude":60.0,
            "location":null,
            "updated_at":"2011-04-14T16:39:47Z",
            "id":3,
            "longitude":30.0,
            "takes_place_at":"2011-03-24T14:00:00Z"
        },
        {
            "name":"ba",
            "created_at":"2011-04-10T22:40:07Z",
            "latitude":60.0,
            "location":"12,
            14",
            "updated_at":"2011-04-10T22:40:07Z",
            "id":4,
            "longitude":30.0,
            "takes_place_at":"2011-04-10T22:36:00Z"
        },
        {
            "name":"sfasdfs",
            "created_at":"2011-04-10T22:44:55Z",
            "latitude":60.0,
            "location":"we're try to find you ...",
            "updated_at":"2011-04-10T22:44:55Z",
            "id":5,
            "longitude":30.0,
            "takes_place_at":"2011-04-10T22:42:00Z"
        },
        {
            "name":"asdfsad",
            "created_at":"2011-04-10T22:55:03Z",
            "latitude":60.0,
            "location":"we're try to find you ..asfd.",
            "updated_at":"2011-04-10T22:55:03Z",
            "id":6,
            "longitude":30.0,
            "takes_place_at":"2011-04-10T22:54:00Z"
        }
    ]
}

我尝试使用 sencha/extjs: 使用该服务，

refresh = function() {
  Ext.util.JSONP.request({
    url: 'http://localhost:3000/search/by_date.json',
    callbackKey: 'callback',
    params: {
      year:"2011",
      month:"04",
      day:"10",
      uniqueify: Math.random()
    },
    callback: function(data) {
      var events = data.results;
      timeline.update(events);
    }
  });
};

但 sencha 只是不解析它。同时，它可以与 Twitter 等 API 调用配合使用。

有什么想法我做错了什么吗？或者我怎样才能找到错误？

Answer 1

如果您正在执行 JSONP 请求，则需要将返回的 JSON 包装在 GET 请求中指定为参数的函数中，在您的例子中为“回调”。 Sencha touch 将在内部处理函数命名，但您确实需要记下传入的callbackKey 选项，以便您的服务器可以正确响应。

请求 http://localhost:3000/search/by_date.json?callback=jsonP2343243243 预期响应时应包装在回调参数指定的函数中。该 GET 请求应生成以下 JSON：

jsonP2343243243({ "results": [ ... ] });

这将导致该函数在被浏览器解释时被调用，然后AJAX 的回调将被调用。在 Rails 中，您需要将渲染更改为：

Rails < 3.0：

format.js { render :js => params[:callback] + "(" + { :results => @events }.to_json + ");"} 

轨道> 3.0

format.js { render :json => { :results => @events },  :callback => params[:callback] }