javascript:dragable div中的图像在拖动时停止拖放

我能做些什么来阻止图像被拖动吗?或者至少触发父母的OnMouseDown事件?

下面是一些HTML示例:

<ul class="asset_list">
  <li id="1"><img src="test1.jpg" />Blah blah blah</li>
  <li id="2"><img src="test2.jpg" />Blah blah blah</li>
  <li id="3"><img src="test3.jpg" />Blah blah blah</li>
</ul>

这里有一些我用来做拖放的JS

// Set up drap and drop
$$( 'ul.asset_list li' ).each( function( item ){
 item.removeEvents();
 item.addEvent('mousedown', function(e) {
  e = new Event(e).stop();

  // Create our clone of the asset for dragging
  var clone = this.clone( true, true );
  clone.removeEvents();
  clone.addClass( "dragging" );
  clone.setStyles(this.getCoordinates()); // this returns an object with left/top/bottom/right, so its perfect

  var drag = clone.makeDraggable({
    droppables: [TrailStream.playlist],
    precalculate: true,
    revert: true,
   }
  }); // this returns the dragged element

  drag.start(e); // start the event manual
 });
});