Pre populating a django form using Initial not working - django

Question

I am trying to save a modelform by prepopulating 'template_name' field . As per django documentation and other threads it is clear that initial parameter should work but i just can't make it work for my code. I am getting the error that template_name field is empty. Any help on what am I missing and any other approach towards this will be great. Here is the code
models.py
class TemplateNameModel(models.Model):
"Model to add the template name"
id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
tna_template_name = models.CharField(verbose_name="Template name",max_length = 128, unique = True,
null = False, blank = False, help_text="please enter name of the new tna template")
description = models.CharField(verbose_name="template description", max_length = 256,
null = True, blank = True, help_text ="Please enter the description(optional)")
created_by = models.TextField(verbose_name="Template created by", max_length= 128,
null = False, blank = False,help_text ="Please enter the name of creator")
date_created = models.DateTimeField(auto_created= True, null = True, blank = True)
is_active = models.BooleanField(verbose_name="Template status",null = False , blank= False)
def __str__(self):
return self.tna_template_name
class TnaTemplateModel(models.Model):
id = models.AutoField(primary_key=True, editable=False)
template_name = models.ForeignKey(TemplateNameModel, verbose_name="template name", null=False,
blank=False, on_delete=models.CASCADE, help_text="Select the template")
process_name = models.ForeignKey(ProcessModel, verbose_name="process name", null=False,
blank=False, on_delete=models.CASCADE, help_text="Select the process")
sequence = models.IntegerField(verbose_name="Process Sequence",null = False,blank = False)
is_base = models.BooleanField()
formula = models.IntegerField(verbose_name="Formula", null= True,blank = True)
remarks = models.CharField(verbose_name="Process remarks", null= True, blank = True,max_length= 300)
class Meta:
unique_together = ["template_name", "process_name"]
def __str__(self):
return str(self.template_name)
forms.py
class ProcessModelformNew(forms.ModelForm):
class Meta:
model = TnaTemplateModel
fields =('__all__')
views.py
def processcreatenew(request,pk):
template_name = TemplateNameModel.objects.get(id=pk)
if request.method == 'POST':
form = ProcessModelformNew(request.POST)
if form.is_valid():
form.save()
else:
data = {'template_name': template_name}
form = ProcessModelformNew(initial= data)
return render (request,"tna/template_tna/baseprocessmodel_create.html",{'form':form})
Html template
<form role="form" method="POST" enctype="multipart/form-data">
{% csrf_token %}
<div class="card-body">
<div class="row">
<div class="col-md-6 col-sm-12">
<!-- text input -->
<div class="form-group">
{{form.process_name|as_crispy_field}}
</div>
</div>
</div>
<div class="row">
<div class="col-md-6 col-sm-12">
<!-- text input -->
<div class="form-group">
{{form.sequence|as_crispy_field}}
</div>
</div>
</div>
<div class="row">
<div class="col-md-6 col-sm-12">
<!-- text input -->
<div class="form-group">
{{form.is_base|as_crispy_field}}
</div>
</div>
<div class="col-md-6 col-sm-12">
<!-- text input -->
<div class="form-group">
{{form.formula|as_crispy_field}}
</div>
</div>
</div>
<div class="row">
<div class="col-md-6 col-sm-12">
<!-- text input -->
<div class="form-group">
{{form.remarks|as_crispy_field}}
</div>
</div>
</div>
</div>
<!-- /.card-body -->
<div class="card-footer">
<button type="submit" class="btn btn-primary">Save</button>
</div>
</form>

Answer 1

You need to render the template_name field in your template so the selected value is passed in the POST data.
{{ form.template_name }}
I suspect you do not want to display the field, you should override it's widget with forms.HiddenInput so that it is not visible to the user
class ProcessModelformNew(forms.ModelForm):
class Meta:
model = TnaTemplateModel
fields = '__all__'
widgets = {'template_name': forms.HiddenInput()}

Answer 2

First method
Include {{ form.template_name }} in your HTML even though you're not want to edit it, just make it hidden
Second method
In your forms.py instead of fields =('__all__') you can put exclude = ['template_name'] so it will no longer required, then in views.py
obj = form.save(commit=False)
obj.template_name = template_name
obj.save()
So if you don't want to include template_name in HTML the second method is good to go, also you don't have to initiate the form

Answer 3

forms.py
def __init__(self, *args, **kwargs):
template_name = kwargs.pop('template_name',None)
self.fields['template_name']= template_name
views.py
inside your model form
def processcreatenew(request,pk):
template_name = TemplateNameModel.objects.get(id=pk)
if request.method == 'POST':
form = ProcessModelformNew(request.POST or None, template_name= template_name)
Something like this you have to perform