将外键值传递给Django中的Choice

Question

I'm a bit confused on how Forms and ModelForms work, I want to create colored buttons based on a field value while creating a form.

{% for category in form.category  %}
<label class="colored-icon btn btn-default btn-sm" style="background-color: {{ category.color }}">
    {{ category.choice_label|slice:"1" }}
    {{ category.tag }}
</label>
{% endfor %}

The problem is that category.color obviously doesn't have value I need.

My form is based on a "Transaction" model. I need to somehow access "color" attribute from "Category" model, which looks like this:

forms.py

class TransactionForm(forms.ModelForm):
    class Meta:
        model = Transaction

models.py

class Transaction(models.Model):
    category = models.ForeignKey(Category, default='Unspecified')

class Category(models.Model):
    color = models.CharField(max_length=10)

views.py

def index(request):
    form = TransactionForm(request.POST)
    new_transaction = form.save()
    context = {
        'form': form,
    }

return render(request, 'index.html', context)

What's the proper way to select and pass "category.color" to each field I'm creating?

Thanks.

Answer 1

Try this:

class Category(models.Model):
    color = models.CharField(max_length=10)

    def __unicode__(self):
        return '%s - %s' % (self.OtherFieldName, self.color)

that way inside the select should look like this

<option value='CategoryID'>OtherFieldName_value - color_value</option>

Answer 2

Alright, I've figured out a way to do so with modified @warath-coder answer. I wasn't able to access "_value" property if it was a way to go, so I had to implement "split" filter and use it to split value I've got and use "color" part of this value.

models.py

class Category(models.Model):
    color = models.CharField(max_length=10)

    def __unicode__(self):
        return '%s - %s' % (self.OtherFieldName, self.color)

split_filter.py

@register.filter(name='split')
def split(value, arg):
    return value.split(arg)

index.html

{% with category.choice_label|split:"-" as label %}
<label class="btn btn-default btn-sm" style="background-color: {{ label.1 }}">
  {{ label.0 }}
  {{ category.tag }}
</label>
{% endwith %}