爲什麼this.helper = null？ （可排序/可拖動/可棄）

Question

爲了防止跌落到垃圾箱後一種可能，我使用

$("#image-ul").sortable('cancel'); 

，但得到的螢火錯誤。一切都按預期工作，但偏執，我做錯了什麼。我可以通過什麼方式停止可丟棄更新後丟棄垃圾？

$(document).ready(function(){ 
    $(function(){ 
     // make the list of images sortable 
     $("#image-ul").sortable({ 
      // allow dragging into the trash can 
      connectWith: '#trash_can', 
      item: 'li', 
      // revert causes bugginess in IE, so left out even though cool 
      //revert: 200, 
      opacity: 0.6, 
      cursor: 'move', 
      // apply this css class to available places to drop within list 
      placeholder: 'placeholder-border', 
      // drop available once mouse has touched droppable area 
      tolerance: 'pointer', 
      update: function(){ 
       var order = $(this).sortable("serialize"); 
       $.post("/drag_drop/update", order, function(theResponse){ 
        // show the confirmation and fade it away after 2.5 seconds 
        $('#content').css('display', 'block'); 
        $('#content').html(theResponse).delay(2500).fadeOut('slow'); 
       }); 
      } 
     }); 
     // allow for deleting images by sending them to the trash can 
     $("#trash_can").droppable({ 
      accept: '#image-ul > li', 
      // when the trash can is hovered on by a draggable, set the css class 
      hoverClass: 'delete-border', 
      drop: function(event, ui) { 
       // setTimeout takes care of IE bug where deleted item remains 
       setTimeout(function() { ui.draggable.remove(); }, 1); 
       deleteImage(ui.draggable); 
      } 
     }); 
     // what to do when an image is dropped into the trash can 
     function deleteImage($draggable){ 
      // strip out "image_data_" so that only the actual image ID is sent to delete query 
      var id = $draggable.attr('id'); 
      id = id.replace('image_data_',''); 
      params = { 
        'id': id, 
        'path': $draggable.find("img").attr("src") 
      } 
      $.ajax({ 
       url: '/drag_drop/delete', 
       type: 'POST', 
       data: params, 
       success: function(delete_response){ 
        $('#content').css('display', 'block'); 
        $('#content').html(delete_response).delay(2500).fadeOut('slow'); 
       } 
      }); 
      $("#image-ul").sortable('cancel'); 
     } 
    }); 
}); 

Answer 1

嘗試，而不是：

$("#image-ul").sortable('disable');