jQuery 自定义事件未在 AJAX 成功回调中触发

Question

I am experimenting with jQuery custom Events in my Application.

In the jQuery AJAX request code below, in the success callback I am trying to trigger() my custom Event

It does not seem to be triggering it though. Will this simply not be able to be done in the success callback and needs to be called elsewhere?

jQuery AJAX request code

// Request Task Record using AJAX Request to Server
var jqXHR = $.ajax({
    type: 'POST',
    async: false,
    contentType: 'application/json; charset=utf-8',
    dataType: 'json',
    url: projectTaskModal.cache.getTaskRecordUrlEndpoint,
    data: {
        action: 'load-task-record',
        task_id: taskId
    },
    success: function(data) {

        // NON RELEVANT CODE REMOVED FOR DEMO

        // Event that is not being triggered....
        // Publish 'task-modal-data-loaded' Event to Subscribers
        $.event.trigger({
            type: 'task-modal-data-loaded',
            source: 'ajax',
            message: 'Task Modal Object Loaded from AJAX Request',
            time: new Date()
        });

    }
}); // end AJAX request

Custom Event Subscriber

$(document).on('task-modal-data-loaded', function(event) {
    //alert('Task Modal Object Loaded');
    console.log('CUSTOM APP EVENTS: Event: task-modal-data-loaded Source: '+event.source+' Message: '+event.message+' Time: '+event.time);
});

Answer 1

From the discussion, The problem is when the event is triggered the handler is not yet added to the dom.

So making sure that the event handler is added before the event is fired will solve the probelm

Answer 2

Have you tried just .trigger() ? jQuery trigger()

from their docs:

$( "#foo" ).on( "custom", function( event, param1, param2 ) {
  alert( param1 + "\n" + param2 );
});
$( "#foo").trigger( "custom", [ "Custom", "Event" ] );

So for your implementation:

$(document).trigger('task-modal-data-loaded',[{
        source: 'ajax',
        message: 'Task Modal Object Loaded from AJAX Request',
        time: new Date()
    }]);

And the listener:

$(document).on('task-modal-data-loaded', function(event,data) {
//alert('Task Modal Object Loaded');
    console.log('CUSTOM APP EVENTS: Event: task-modal-data-loaded Source:    '+
      data.source + ' Message: ' + data.message + ' Time: ' + data.time);
});