How to use Custom JS with Django inline

I have Django applicat开发者_如何学编程ion with inline in place:

class Account(models.Model):
    ContractNum = models.PositiveIntegerField(unique=True, blank=True, null=True)
    LastName = models.CharField(max_length=50,)
    FirstName = models.CharField(max_length=50, )

class Subscription(models.Model):
    Account = models.ForeignKey(Account, related_name='AccountLine')
    IpAddress = models.IPAddressField(unique=True, default=getFreeIP)
    MacAddress = MACAddressField() 
    Switch = models.ForeignKey(Switch, related_name='SwitchAccounts')
    Port = models.ForeignKey(Port )

In admin interface I have inline for the Account class. As a result I have HTML generated like this:

              <td class="Switch">
                  <select name="AccountLine-0-Switch" id="id_AccountLine-0-Switch">
<option value="">---------</option>
<option value="1">ds34/33-2</option>
<option value="8" selected="selected">ds34-1</option>
</select><a href="/admin/cmdb/switch/add/" class="add-another" id="add_id_AccountLine-0-Switch" onclick="return showAddAnotherPopup(this);"> <img src="/admin_media/img/admin/icon_addlink.gif" width="10" height="10" alt="Add one more"/></a>    
              </td>
              <td class="Port">
                  <select name="AccountLine-0-Port" id="id_AccountLine-0-Port">
<option value="">---------</option>
<option value="1">3com34:1</option>
<option value="161" selected="selected">ds34-1:1</option>
</select><a href="/admin/cmdb/port/add/" class="add-another" id="add_id_AccountLine-0-Port" onclick="return showAddAnotherPopup(this);"> <img src="/admin_media/img/admin/icon_addlink.gif" width="10" height="10" alt="Add one more"/></a>

I'm not really good on JavaScript, could you please help me to prepopulate Port option-box, according to choosed Switch option-box? What I've already done: Created JSON query, and view, which returns ports for specific swicth, what I don't know how to do is how to hanlde dynamic id's for inline fields, and how to do this automatically when you add one more row? Thank you for any idea and help in advance.

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I did as you recommended, in that post, and it's working pretty fine, here is JavaScript I've made:

$(document).ready(function() {
        $(".module").delegate("[id$=-Switch]", "change", function() {
            var row = $(this).attr("id").split('id_AccountLine-')[1].split("-Switch")[0];
            var switch_id = $(this).val();
        var json_url = "/admin/cmdb/switch_ports/"+switch_id+"/"
            $("#id_AccountLine-"+row+"-Port").html("");
        $.post("/admin/cmdb/switch_ports/"+switch_id+"/", { "func": "getNameAndTime" },
                function(data){
            for ( var i = 0; i < data.length; i++) {
                var onePort = "<option value=\""+data[i].pk+"\">"+data[i].fields.PortNum+"</option>";
                $("#id_AccountLine-"+row+"-Port").append(onePort);
            }
                }, "json");
        });
    });