Right click on page to display menu, move to the 'Open' item to display its custom sub content.
<div id="mm" style="width:120px;">
<div>New</div>
<div>
<span>Open</span>
<div class="menu-content" style="text-align:left;padding:10px">
<div style="font-weight:bold;font-size:14px;margin-bottom:10px">Select Your Language:</div>
<ul id="tt">
<li>Java</li>
<li>Basic</li>
<li>C++</li>
<li>Fortran</li>
</ul>
</div>
</div>
<div data-options="iconCls:'icon-save'">Save</div>
<div data-options="iconCls:'icon-print'">Print</div>
<div class="menu-sep"></div>
<div>Exit</div>
</div>
<script>
$(function(){
$('#mm').menu();
$('#tt').tree();
$("#demo_region").bind('contextmenu',function(e){
e.preventDefault();
$('#mm').menu('show', {
left: e.pageX,
top: e.pageY
});
});
});
</script>