当选择了正确的值时，我想在模态对话框中打开id =“new_firm”的div。我无法打开对话框。我知道自弹出警报以来脚本已执行。谁能告诉我这里有什么问题？
<!DOCTYPE html>
<html>
<head>
<title>FileReader Example</title>
<link rel="stylesheet" type="text/css" href="css/jquery.mobile-1.0.css" />
<script type="text/javascript" charset="utf-8" src="js/jquery-1.7.1.js"></script>
<script type="text/javascript" charset="utf-8" src="js/jquery.mobile-1.0.js"></script>
<script type="text/javascript" charset="utf-8" src="js/phonegap-1.3.0.js"></script>
<script type="text/javascript" charset="utf-8">
function openNewFirmDialog() {
var selected = $("#select_firm option:selected");
var ddValue = selected.text();
if(ddValue === "Add a new company") {
//alert(ddValue);
$('#new_firm').dialog({modal:true});
}
}
</script>
</head>
<body>
<div data-role="page" id="add_details">
<div data-role="content">
<h2>Register hours</h2>
<a href="#new_firm" data-rel="dialog">hei</a>
<div data-role="fieldcontain">
<select id="select_firm" data-native-menu="false" onchange="openNewFirmDialog()">
<label for="select_firm" class="select">Select firm:</label>
<option data-placeholder="firm">Firm</option>
<option value="internal">Internal</option>
<option value="new_firm_option">Add a new company</option>
</select>
</div>
<input type="text" id="descritptionTxt" value="Description"/>
<div data-role="controllgroup" data-type="horizontal">
<input type="range" id="number_of_hours" min="0" max="24" step="0.25" value="0" />
<input type="range" id="number_of_minutes" min="0" max="24" step="0.25" value="0" />
</div>
</div>
<div data-role="footer" data-position="fixed">
<div data-role="navbar">
<ul>
<li><a href="index.html" data-icon="home">Overview</a></li>
<li><a href="add.html" data-icon="plus">Add hours</a> </li>
<li><a href="settings.html" data-icon="gear">Settings</a></li>
</ul>
</div>
</div>
</div>
<div data-role="page" id="new_firm">
<h2>Add a new firm</h2>
<textarea id="the_new_firm" value="New firm"/>
</div>
</body>