Passing data from django form to ListView

Question

Above is an image of what I am attempting to build: A form that is at the top while the area to display a result list is below. When I hit 'Go!', the part below does not render the list as I hoped. Also, I am not sure if this is the 'proper' way to go about doing this.

The Class Based View that i use:

class EntryListView(ListView):
    template_name = 'finance/entry_list.html'
    now = datetime.now()
    year = now.year
    context_object_name = 'entry_list'
    model = Entry
    paginate_by = 10
    month_list = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October',
                  'November', 'December']
    year_list = list(range(Entry.objects.earliest('input_date').input_date.year,
                           Entry.objects.latest('input_date').input_date.year))

    def get_context_data(self, **kwargs):
        context = super(EntryListView, self).get_context_data(**kwargs)

        # https://stackoverflow.com/questions/18232851/django-passing-variables-to-templates-from-class-based-views
        context.update({
            'month_list': self.month_list,
            'year_list': self.year_list,
        })
        return context

    # This method ensures that I can customize the list of entries returned.
    def get_queryset(self):

        # https://stackoverflow.com/questions/22902457/django-listview-customising-queryset
        if self.request.method == 'GET':
            print('I have entered here!')
            month = self.request.GET.get('month')
            year = self.request.GET.get('year')
            print('month: ' + str(month))
            print('year: ' + str(year))
            if month or year is None:
                return Entry.objects.filter(input_date__month=datetime.now().month,
                                            input_date__year=datetime.now().year).order_by('-input_date').all()
            else:
                return Entry.objects.filter(input_date__month=month,
                                            input_date__year=year).order_by('-input_date').all()

Here is my urls.py:

url(r'entry/$', login_required(views.EntryListView.as_view()), name='list_entries'),

The EntryListView is also in charged of ensuring that the form is populated with the right 'Dropdown values'.

And here is the template:

{% extends 'base.html' %}
{% block body_content %}
    <div class="wrapper">
        {% include 'finance/finance_sidebar.html' %} <!-- Add this for inheritance -->
        <div class="container">
            <div class="row">
                <form class="well contact-form" method='GET'>
                    <label>Month:</label>
                    <select class="well form-control" name="month">
                        {% for month in month_list %}
                            <option value="{{ forloop.counter }}">{{ month }}</option>
                        {% endfor %}
                    </select>
                    <label>Year:</label>
                    <select class="well form-control" name="year">
                        {% for year in year_list %}
                            <option value="{{ year }}">{{ year }}</option>
                        {% endfor %}
                    </select>
                    <button type="submit" class="btn btn-default">Go!</button>
                </form>
            </div>
            <div class="row">
                {% if entry_list %}
                <div class="container">
                    <table class="table table-hover">
                        <thead>
                            <tr>
                                <th>No.</th>
                                <th width="100">Input Date</th>
                                <th>Category</th>
                                <th>Tag</th>
                                <th>Description</th>
                                <th>Value</th>
                                <th>Transfer Type</th>
                                <th>Remarks</th>
                                <th>Edit</th>
                                <th>Delete</th>
                            </tr>
                        </thead>
                        <tbody>
                        {% for entry in entry_list %}
                            <tr>
                                <td>{{ forloop.counter }}</td>
                                <td>{{ entry.input_date|date:'d M Y' }}</td>
                                <td>{{ entry.category }}</td>
                                <td>{{ entry.tag }}</td>
                                <td>{{ entry.description }}</td>
                                <td>${{ entry.value }}</td>
                                <td>{{ entry.transfer_type }}</td>
                                <td>{{ entry.remarks }}</td>
                                <td>
                                    <form class="flex-container" method="post" action="{% url 'finance:update_entry' pk=entry.id %}" >
                                        {% csrf_token %}
                                        <div class="input-group">
                                            <input type="hidden" name="id" value="{{ entry.id }}">
                                            <button name="update" type="submit" class="btn btn-warning">EDIT </button>
                                        </div>
                                    </form>
                                </td>
                                <td>
                                    <form class="flex-container" method="post" action="{% url 'finance:delete_entry' %}" >
                                        {% csrf_token %}
                                        <div class="input-group">
                                            <input type="hidden" name="id" value="{{ entry.id }}">
                                            <button name="delete" type="submit" class="btn btn-danger">DELETE </button>
                                        </div>
                                    </form>
                                </td>
                            </tr>
                        {% endfor %}
                        </tbody>
                    </table>
                </div>
                <div class="col-sm-7 col-sm-offset-5">
                    {% if is_paginated %}
                        <div class="pagination">
                            <span class="page-links">
                                {% if page_obj.has_previous %}
                                    <a href="/?page={{ page_obj.previous_page_number }}">previous</a>
                                {% endif %}
                                <span class="page-current">
                                    Page {{ page_obj.number }} of {{ page_obj.paginator.num_page }}.
                                </span>
                                {% if page_obj.has_next %}
                                    <a href="/?page={{ page_obj.next_page_number }}">next</a>
                                {% endif %}
                            </span>
                        </div>
                    {% endif %}
                </div>
            {% else %}
                <p>Please make sure you have specified a month and the year.</p>
            {% endif %}
            </div>
        </div>
    </div>
{% endblock %}

I am again, not sure if this is the right way to approach it. I have seen something called Mixins, but I have no clue how to use them. I did a little print statements while debugging and i found that the data from the forms indeed are able to be accessed inside the get_queryset() method. I also made sure that my DB had such a record and i even typed it in my python shell to be sure that the query is not faulty.

Answer 1

Your if-else statement in your view is wrong. if month or year is None: will always evaluate to true since it can be rewritten as if (month) or (year is None) and you are actually posting month value to your view.

Instead, you could rewrite it as: if month is None or year is None:.