How to read/write input fields in Django-admin tabular inlines using ajax?

Question

I am looking for ways to dynamically update the inline entries using ajax. i.e. as the user selects an item from the dropdown box, the associated input fields can be populated with data.

The views.py part for ajax should be straightforward. But one problem for me is how to get the names of dropdown boxes in js, which can be added on the fly.

Below are the models.py and admin.py:

models.py

class Tshirt:
    designer = CharField()
    default_wording = CharField()

class Order:
    date = DateField()

class Order_item:
    order = ForeignKey(Order, related_name='order')
    tshirt = ForeignKey(Tshirt)
    wording = CharField()

admin.py

class Order_Inline(TabularInline):
    model = Order_item
    fk_name = 'order'

class Order_Admin(ModelAdmin):
    inlines = [Order_Inline,]

Answer 1

1. urls.py

   from django.conf import settings
   
   
   urlpatterns = patterns('',
       (r'^json/tshirt/$', json_order),
       (r'^site_media/(?P<path>.*)$', 'django.views.static.serve', {'document_root': settings.MEDIA_ROOT}),
       ...
   )
   

2. views.py

   from django.core import serializers
   
   
   def json_order(request):
       search = request.GET.get('tshirt_id')
       if search:
           result = Tshirt.objects.filter(id=search)
           return HttpResponse(serializers.serialize('json', result, fields=('default_wording')), mimetype='application/json')
       return HttpResponse()
   

3. admin.py

   class Order_Inline(TabularInline):
       model = Order_item
       fk_name = 'order'
   
   
   class Order_Admin(ModelAdmin):
       inlines = [Order_Inline,]
       class Media:
           js = ('/media/js/jquery.js', '/site_media/js/tshirt.js',)
   

4. _settings.MEDIA_ROOT_/js/tshirt.js

   $(document).ready(function() {
       $(".module").delegate("[id$=-tshirt]", "change", function() {
           var row = $(this).attr("id").split('id_order_item-')[1].split("-tshirt")[0];
           var tshirt_id = $(this).val();
           var data = {"tshirt_id":tshirt_id};
           $.getJSON("/json/tshirt", data, function(data) {
               var dw = data[0]["fields"]["default_wording"];
               $("input[id='id_item-"+row+"-wording']").val(dw);
           });
       });
   });