jQuery UI的Draggable handle选项

jQuery UI是一种基于网络的技术，由使用jQuery JavaScript库实现的GUI部件、视觉效果和主题组成。jQuery UI是为网页建立UI界面的最佳工具。它也可以用来建立高度互动的网络应用程序，或者可以用来轻松地添加小工具。

在这篇文章中，我们将学习如何使用jQuery UI的Draggable handle选项。这个选项限制了拖动的开始，除非mousedown发生在指定的元素（s）。只有从可拖动元素下降的元素才被允许。这个选项的默认值是false。

语法:

处理选项需要一个选择器或元素类型的值，语法如下。

$( ".selector" ).draggable({ handle: "h2" });

获取handle选项

var handle = $( ".selector" ).draggable( "option", "handle" );

设置handle选项

$( ".selector" ).draggable( "option", "handle", "h2" );

CDN链接：你的项目将需要以下jQuery Mobile脚本，所以我们需要将这些脚本添加到你的项目中。

<link href = “https://code.jquery.com/ui/1.10.4/themes/ui-lightness/jquery-ui.css” rel = “stylesheet”>
<script src = “https://code.jquery.com/jquery-1.10.2.js”></script>
<script src = “https://code.jquery.com/ui/1.10.4/jquery-ui.js”></script>

例子：这个例子描述了jQuery UI Draggable handle Option的用途。

<!DOCTYPE html>
<html lang="en">
<head>
    <link rel="stylesheet"
          href=
"https://code.jquery.com/ui/1.10.4/themes/ui-lightness/jquery-ui.css">
    <script src=
"https://code.jquery.com/jquery-1.10.2.js">
    </script>
    <script src=
"https://code.jquery.com/ui/1.10.4/jquery-ui.js">
    </script>
    <style>
        .dragg {
            width: 120px;
            height: 60px;
            border: 1px solid black;
            background-color: blue;
        }
  
        .dropp2{
            width: 250px;
            height: 50px;
            border: 1px solid black;
            float: center;
            background-color: green;
        }
          
        #btn
        {
            padding: 0.5;
            font-size: 20px;
            height: 40px;
            width: 40%;
        }
    </style>
    <script>
         $(function () {$ ("#btn").on('click', function () {
                var handle =  $(".dragg") .draggable( "option", "handle" ); document.getElementById('gfg').innerHTML += "Handle Value: " + handle; }); });$ (function () {
             $(".dragg").draggable();$ (".dragg").draggable({
              handle: "p"
            });
             $(".dropp2").droppable({ drop: function (event, ui) {$ (this)
                        .find("p")
                        .html("Dropped!");
                }
            });
        });
    </script>
</head>
<body>
    <center>
        <h1 style="color:green;">GeeksforGeeks</h1>
        <h3>jQuery UI Draggable handle Option</h3>
        <div class="dragg">
            <p>Drag</p>
        </div>
        <br>
        <div class="dropp2">
            <p>Drop here</p>
        </div>
        <br>
        <input type="button" id="btn"
            value="Get Handle">
        <h3><span id="gfg"></span></h3>
    </center>
</body>
</html>

输出:

jQuery UI的Draggable handle选项