HTML5 dragend event firing immediately

问题

I have several draggable elements

<div Class="question-item" draggable="true">Box 1: Milk was a bad choice.</div>
<div class="question-item" draggable="true">Box 2: I'm Ron Burgundy?</div>
<div class="question-item" draggable="true">Box 3: You ate the entire wheel of cheese?     </div>
<div class="question-item" draggable="true">Box 4: Scotch scotch scotch</div>

And I have the following event handlers:

var $questionItems = $('.question-item');

$questionItems
  .on('dragstart', startDrag)
  .on('dragend', removeDropSpaces)
  .on('dragenter', toggleDropStyles)
  .on('dragleave', toggleDropStyles);


function startDrag(e){
  console.log('dragging...');
  addDropSpaces();
  e.stopPropagation();
}

function toggleDropStyles(){
  $(this).toggleClass('drag-over');
  console.log(this);
}


function addDropSpaces(){
  $questionItems.after('<div class="empty-drop-target"></div>');
}

function removeDropSpaces(){
  console.log("dragend");
  $('.empty-drop-target').remove()
}

Why does it only work for the first draggable. If I drag say the last draggable - the dragend event is fired immediately. (I don't want to use jQuery UI btw)

It makes no sense to me - it looks like a bug.

I am on Chrome v 30 on OSX.

Here is a link to the JSFiddle: http://jsfiddle.net/joergd/zGSpP/17/

(Edit: this is repeat of the following question: dragend, dragenter, and dragleave firing off immediately when I drag - but I think the original poster was fine to go with jQuery UI, whereas I want it to be HTML5 native)

回答1:

As i mentioned in the topic dragend, dragenter, and dragleave firing off immediately when I drag , what solved the problem (which looks to be a Chrome bug) for me was to add a setTimeout of 10 milliseconds into the handler and manipulate the DOM in that timeout.

回答2:

I don't have a direct solution, but changing the DOM in the dragStart event handler is causing this problem, and any code that changes the DOM should really go in the dragEnter event handler - doing so, drag&drop events are fired more reliably.

Not sure whether this is by design - it feels a bit like a bug though.