Dynamically adding a form to a Django formset with Ajax

Question

I want to automatically add new forms to a Django formset using Ajax, so that when the user clicks an \"add\" button it runs JavaScript that adds a new form (which is part o

Answer 1

There is a jquery plugin for this, I used it with inline_form set in Django 1.3, and it works perfectly, including prepopulation, client side form adding, removing, and multiple inline_formsets.

Answer 2

For the coders out there who are hunting resources to understand the above solutions a little better:

Django Dynamic Formsets

After reading the above link, the Django documentation and previous solutions should make a lot more sense.

Django Formset Documentation

As a quick summary of what I was getting confused by: The Management Form contains an overview of the forms within. You must keep that information accurate in order for Django to be aware of the forms you add. (Community, please give me suggestions if some of my wording is off here. Im new to Django.)

Answer 3

This is how I do it, using jQuery:

My template:

<h3>My Services</h3>
{{ serviceFormset.management_form }}
{% for form in serviceFormset.forms %}
    <div class='table'>
    <table class='no_error'>
        {{ form.as_table }}
    </table>
    </div>
{% endfor %}
<input type="button" value="Add More" id="add_more">
<script>
    $('#add_more').click(function() {
        cloneMore('div.table:last', 'service');
    });
</script>

In a javascript file:

function cloneMore(selector, type) {
    var newElement = $(selector).clone(true);
    var total = $('#id_' + type + '-TOTAL_FORMS').val();
    newElement.find(':input').each(function() {
        var name = $(this).attr('name').replace('-' + (total-1) + '-','-' + total + '-');
        var id = 'id_' + name;
        $(this).attr({'name': name, 'id': id}).val('').removeAttr('checked');
    });
    newElement.find('label').each(function() {
        var newFor = $(this).attr('for').replace('-' + (total-1) + '-','-' + total + '-');
        $(this).attr('for', newFor);
    });
    total++;
    $('#id_' + type + '-TOTAL_FORMS').val(total);
    $(selector).after(newElement);
}

What it does:

cloneMore accepts selector as the first argument, and the type of formset as the 2nd one. What the selector should do is pass it what it should duplicate. In this case, I pass it div.table:last so that jQuery looks for the last table with a class of table. The :last part of it is important because the selector is also used to determine what the new form will be inserted after. More than likely you'd want it at the end of the rest of the forms. The type argument is so that we can update the management_form field, notably TOTAL_FORMS, as well as the actual form fields. If you have a formset full of, say, Client models, the management fields will have IDs of id_clients-TOTAL_FORMS and id_clients-INITIAL_FORMS, while the form fields will be in a format of id_clients-N-fieldname with N being the form number, starting with 0. So with the type argument the cloneMore function looks at how many forms there currently are, and goes through every input and label inside the new form replacing all the field names/ids from something like id_clients-(N)-name to id_clients-(N+1)-name and so on. After it is finished, it updates the TOTAL_FORMS field to reflect the new form and adds it to the end of the set.

This function is particularly helpful to me because the way it is setup it allows me to use it throughout the app when I want to provide more forms in a formset, and doesn't make me need to have a hidden "template" form to duplicate as long as I pass it the formset name and the format in which the forms are laid out. Hope it helps.