I have a Many-To-Many relationship between a Course and Tutor model. I am trying to make it so that when you use a form to create a record for a new Tutor, you can select the courses they can teach. I tried using and modifying the code from this previous question as best I could, but I don't fully understand it so I'm sure I didn't do it right. When the form is submitted, it won't save the link between the Courses and Tutor. What do I need to change about the code to make it save?
models.py
class Tutor(models.Model):
FirstName = models.CharField(max_length=50)
LastName = models.CharField(max_length=50)
Email = models.EmailField(max_length=100)
PhoneNumber = models.CharField(max_length=10, )
RequestedHours = models.DecimalField(max_digits=3, decimal_places=1)
class Course(models.Model):
SubjectID = models.ForeignKey(Subject, related_name='subjectCourse')
Department = models.CharField(max_length=4)
Number = models.CharField(max_length=4)
Name = models.CharField(max_length=200)
TutorForCourse = models.ManyToManyField(Tutor)
forms.py
class TutorForm(forms.ModelForm):
class Meta:
model = Tutor
fields = ('FirstName', 'LastName', 'Email', 'PhoneNumber',
'RequestedHours',)
labels = {
'FirstName': 'First Name',
'LastName': 'Last Name',
'Email': 'Email',
'PhoneNumber': 'Phone Number',
'RequestedHours': 'Requested Hours',
}
courses = forms.ModelMultipleChoiceField(queryset=Course.objects.all())
def __init__(self, *args, **kwargs):
# Only in case we build the form from an instance
# (otherwise, 'toppings' list should be empty)
if kwargs.get('instance'):
# We get the 'initial' keyword argument or initialize it
# as a dict if it didn't exist.
initial = kwargs.setdefault('initial', {})
# The widget for a ModelMultipleChoiceField expects
# a list of primary key for the selected data.
initial['courses'] = [t.pk for t in
kwargs['instance'].course_set.all()]
forms.ModelForm.__init__(self, *args, **kwargs)
# Overriding save allows us to process the value of 'toppings' field
def save(self, commit=True):
# Get the unsaved Pizza instance
instance = forms.ModelForm.save(self, False)
# Prepare a 'save_m2m' method for the form,
old_save_m2m = self.save_m2m
def save_m2m():
old_save_m2m()
# This is where we actually link the pizza with toppings
instance.course_set.clear()
for course in self.cleaned_data['courses']:
instance.course_set.add(course)
self.save_m2m = save_m2m
# Do we need to save all changes now?
if commit:
instance.save()
self.save_m2m()
return instance
views.py
@login_required
def tutor_new(request):
if request.method == "POST":
form = TutorForm(request.POST)
if form.is_valid():
tutor = form.save(commit=False)
tutor.save()
tutors = Tutor.objects.filter()
return render(request, 'portfolio/tutor_list.html',
{'tutors': tutors})
else:
form = TutorForm()
# print("Else")
return render(request, 'portfolio/tutor_new.html', {'form': form})
