Django widget override template

Question

I am new at django.

I want to create a custom widget.

forms.py:

from project.widgets import MultiChoiceFilterWidget

class CustomSearchForm(FacetedSearchForm):
    TEST_COLORS = [
        u"Blau", u"Rot", u"Gelb"
    ]

    color = forms.MultipleChoiceField(
        label=_("Color"), choices=[(x, x) for x in TEST_COLORS],
        widget=MultiChoiceFilterWidget, required=False)

widget.py:

class MultiChoiceFilterWidget(forms.widgets.CheckboxSelectMultiple):
    template_name = 'project/widgets/filter.html'
    option_template_name = 'ptoject/widgets/filter_option.html'

project/widgets/filter.html:

 <h1>TEST</h1>

But it doesn't render the new template, instead it still renders the old way.

Can you give me some tips?

Answer 1

You will have to do the below steps to render your new widget template:

1) Add 'django.forms' to your INSTALLED_APPS;

2) Add FORM_RENDERER = 'django.forms.renderers.TemplatesSetting' to your settings.py.

More details : https://docs.djangoproject.com/en/2.0/ref/forms/renderers/#django.forms.renderers.TemplatesSetting

Answer 2

Django version < 1.11:

The widget must implement the render method in order to render a different template:

from django.utils.safestring import mark_safe
from django.template.loader import render_to_string

class MultiChoiceFilterWidget(forms.widgets.CheckboxSelectMultiple):
    template_name = 'project/widgets/filter.html'

    def render(self, data):
        ...
        Do stuff with data
        ...
        return mark_safe(render_to_string(self.template_name))

---

Django version 1.11:

In the renderer's documentation, we can find the following:

New in Django 1.11:

In older versions, widgets are rendered using Python. All APIs described in this document are new.

And by having a look at the widget source code and specifically on how the Input widget extends the Widget class, we can see that you would only need to customize your widget as follows:

class MultiChoiceFilterWidget(forms.widgets.CheckboxSelectMultiple):
    template_name = 'project/widgets/filter.html'

Which is what you have already.

Answer 3

If you only need to change the templates, redefining a complete widget is tedious for nothing. Since the widget is passed to the field as an instance, you can instanciate the base widget you want to use and change the templates afterward.

class CustomSearchForm(FacetedSearchForm):
TEST_COLORS = [
    u"Blau", u"Rot", u"Gelb"
]

color = forms.MultipleChoiceField(
    label=_("Color"), choices=[(x, x) for x in TEST_COLORS],
    widget=forms.widgets.CheckboxSelectMultiple, required=False)
color.widget.template_name = 'project/widgets/filter.html'
color.widget.option_template_name = 'project/widgets/filter_option.html'

If you need to pass custom data to your templates, then you will have to create a custom widget.