Question

我想知道是否有人知道在发布的事件完成后将事件/回调附加到dojo发布的方法。

我将某些内容发布为委派任务，当委派任务完成时，我想进行一些UI更改。

如果您知道如何知道这是不可能的，请告诉我。

编辑：如果我能够在发布的事件结束后向发布者返回一个值，我想我也可以做我想做的事。

Answer 1

让我们试试这样的事情

// publisher side
var d = new dojo.Deferred();
dojo.publish("my/channel",[d]);
// ... do some extra asynchronous work , server request ...
result = goterror ? "error" : "ok";
if (!error) d.callback(result); else d.errback(result);

// listener side
dojo.subscribe("my/channel",function(d) {
  // let's wait for the server to respond ( or maybe its already done )
  d.then(function(result) {
    // result is "ok"
  },function(params) {
    // result is "error"
  });
});

Answer 2

我不知道这样做的“正确”方法，但您可以尝试使用单独的频道并按照惯例强制执行连接：

dojo.subscribe('fooChannel', function(){
     ....
     dojo.publish('fooChannelComplete', [...]);
});

帮助函数更加无缝：

function add_to_foo(f){
    dojo.subscribe('fooChannel', function(){
        var ret = f.apply(this, arguments);
        dojo.publish('fooChannelComplete', [ret]);
    });
}

Answer 3

建立在@ Sebastien的前提下：

//publisher
var deferred = new Dojo.deferred();
var successFunction = function(){
  console.log('task succesfully completed');
};

var errorFunction = function(){
  console.log('task did not succesfully complete');
};
//when our deferred object is done, invoke either successFunction or errorFunction
dojo.when(deferred, successFunction, errorFunction);

dojo.publish("someTopic",[deferred]);




//topic subscriber code
dojo.subscribe("someTopic",function(deferred) {
  //do whatever delegated task is needed.
  //...

  //task completed successfully, invoke the `successFunction` defined on the publisher
  deferred.callback();  

  //or if task did not complete successfully invoke `errorFunction` defined on the publisher
  //deferred.errback();

});

同样的前提，但使用dojo.when IMO是更好的语法糖。

将回调附加到发布

3 个答案: