id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
25023	Many to Many through - save new Data	trap12	nobody	"Hi,

I am new in Django and have problems with the M2M-Fields with a custom join table (through).  I want to to save new Data (no duplicate). But the form shows me just the data in the db, which I can select.
I have no access to the through-table ""RecipeIngredients"" which links the ingredient with the recipe and holds the quantity.

I want to have a dynamic field, where I can add also new ingredient, which are not in the db. And I want to add the field quanity in the RecipeForm. (problem: the quantity field is not in the model Recipe, it is in the RecipeIngredients)

models.py: 
{{{
class Ingredient(models.Model):
    id = models.AutoField(primary_key=True)
    name = models.CharField(max_length=200)

class Recipe(models.Model):
    id = models.AutoField(primary_key=True)
    recipename = models.CharField(max_length=200)
    author = models.ForeignKey(Student, null=True)
    pub_date = models.DateTimeField('date published', editable=False)
    ingredients = models.ManyToManyField(Ingredient, through='Recipeingredients')
    description = models.CharField(max_length=20000)

     
class Recipeingredients(models.Model):
    id = models.AutoField(primary_key=True)
    ingredient = models.ForeignKey(Ingredient)
    recipe = models.ForeignKey(Recipe)
    quantity = models.CharField(max_length=30)
}}}

forms.py:

{{{

class RecipeForm(forms.ModelForm):
    class Meta:
        model = Recipe
        exclude = ('id', 'author', 'pub_date')

}}}

views.py:

{{{

@login_required
def create(request):
    if request.method == 'POST':
        form = RecipeForm(user=request.user, data=request.POST)
        if form.is_valid():
            recipe = form.save()
            
            return HttpResponseRedirect(recipe.get_absolute_url())
    else:
        form = RecipeForm()
        
    return render(request, 'recipes/create.html', {'form': form}}

}}}
create.html:

{{{
<form action=""{{ action_url }}"" method=""post"" accept-charset=""utf-8"">
    {{ form.as_p }}
    {% csrf_token %}
    
    <p><input type=""submit"" value=""Save""/></p>
</form>
}}}

Like I said, I have no textfield to add new ones.

Do you know what I have to change?

thanks in advance!!!

regards,
trap123
"	Cleanup/optimization	closed	Forms	1.8	Normal	invalid			Unreviewed	0	0	0	0	0	0