当悬停在 droppable 上时,或者当 droppable 被激活(即一个可接受的 draggable 被放置在 droppable 上)时,改变 droppable 的外观。使用 hoverClassactiveClass 选项来分别指定 class。

当悬停在 droppable 上时的反馈:

请拖拽我到目标

请放置在这里

当激活 draggable 时的反馈:

请拖拽我到目标

请放置在这里

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>jQuery UI 放置(Droppable) - 视觉反馈</title>
  <link rel="stylesheet" href="//code.jquery.com/ui/1.10.4/themes/smoothness/jquery-ui.css">
  <script src="//code.jquery.com/jquery-1.9.1.js"></script>
  <script src="//code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
  <link rel="stylesheet" href="http://jqueryui.com/resources/demos/style.css">
  <style>
  #draggable, #draggable2 { width: 90px; height: 90px; padding: 0.5em; float: left; margin: 10px 10px 10px 0; }
  #droppable, #droppable2 { width: 120px; height: 120px; padding: 0.5em; float: left; margin: 10px; }
  h3 { clear: left; }
  </style>
  <script>
  $(function() {
    $( "#draggable" ).draggable();
    $( "#droppable" ).droppable({
      hoverClass: "ui-state-hover",
      drop: function( event, ui ) {
        $( this )
          .addClass( "ui-state-highlight" )
          .find( "p" )
            .html( "Dropped!" );
      }
    });
 
    $( "#draggable2" ).draggable();
    $( "#droppable2" ).droppable({
      accept: "#draggable2",
      activeClass: "ui-state-default",
      drop: function( event, ui ) {
        $( this )
          .addClass( "ui-state-highlight" )
          .find( "p" )
            .html( "Dropped!" );
      }
    });
  });
  </script>
</head>
<body>
 
<h3>当悬停在 droppable 上时的反馈:</h3>
 
<div id="draggable" class="ui-widget-content">
  <p>请拖拽我到目标</p>
</div>
 
<div id="droppable" class="ui-widget-header">
  <p>请放置在这里</p>
</div>
 
<h3>当激活 draggable 时的反馈:</h3>
 
<div id="draggable2" class="ui-widget-content">
  <p>请拖拽我到目标</p>
</div>
 
<div id="droppable2" class="ui-widget-header">
  <p>请放置在这里</p>
</div>
 
 
</body>
</html>