Django set default form values - python

I have a Model as follows:
class TankJournal(models.Model):
user = models.ForeignKey(User)
tank = models.ForeignKey(TankProfile)
ts = models.IntegerField(max_length=15)
title = models.CharField(max_length=50)
body = models.TextField()
I also have a model form for the above model as follows:
class JournalForm(ModelForm):
tank = forms.IntegerField(widget=forms.HiddenInput())
class Meta:
model = TankJournal
exclude = ('user','ts')
I want to know how to set the default value for that tank hidden field. Here is my function to show/save the form so far:
def addJournal(request, id=0):
if not request.user.is_authenticated():
return HttpResponseRedirect('/')
# checking if they own the tank
from django.contrib.auth.models import User
user = User.objects.get(pk=request.session['id'])
if request.method == 'POST':
form = JournalForm(request.POST)
if form.is_valid():
obj = form.save(commit=False)
# setting the user and ts
from time import time
obj.ts = int(time())
obj.user = user
obj.tank = TankProfile.objects.get(pk=form.cleaned_data['tank_id'])
# saving the test
obj.save()
else:
form = JournalForm()
try:
tank = TankProfile.objects.get(user=user, id=id)
except TankProfile.DoesNotExist:
return HttpResponseRedirect('/error/')

You can use Form.initial, which is explained here.
You have two options either populate the value when calling form constructor:
form = JournalForm(initial={'tank': 123})
or set the value in the form definition:
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)

Other solution: Set initial after creating the form:
form.fields['tank'].initial = 123

If you are creating modelform from POST values initial can be assigned this way:
form = SomeModelForm(request.POST, initial={"option": "10"})
https://docs.djangoproject.com/en/1.10/topics/forms/modelforms/#providing-initial-values

I had this other solution (I'm posting it in case someone else as me is using the following method from the model):
class onlyUserIsActiveField(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(onlyUserIsActiveField, self).__init__(*args, **kwargs)
self.fields['is_active'].initial = False
class Meta:
model = User
fields = ['is_active']
labels = {'is_active': 'Is Active'}
widgets = {
'is_active': forms.CheckboxInput( attrs={
'class': 'form-control bootstrap-switch',
'data-size': 'mini',
'data-on-color': 'success',
'data-on-text': 'Active',
'data-off-color': 'danger',
'data-off-text': 'Inactive',
'name': 'is_active',
})
}
The initial is definded on the __init__ function as self.fields['is_active'].initial = False

As explained in Django docs, initial is not default.
The initial value of a field is intended to be displayed in an HTML . But if the user delete this value, and finally send back a blank value for this field, the initial value is lost. So you do not obtain what is expected by a default behaviour.
The default behaviour is : the value that validation process will take if data argument do not contain any value for the field.
To implement that, a straightforward way is to combine initial and clean_<field>():
class JournalForm(ModelForm):
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
(...)
def clean_tank(self):
if not self['tank'].html_name in self.data:
return self.fields['tank'].initial
return self.cleaned_data['tank']

If you want to add initial value and post other value you have to add the following :
or None after request.POST
form = JournalForm(request.POST or None,initial={'tank': 123})
If you want to add files or images also
form = JournalForm(request.POST or None,request.FILES or None,initial={'tank': 123})

I hope this can help you:
form.instance.updatedby = form.cleaned_data['updatedby'] = request.user.id

I also encountered the need to set default values in the form during development. My solution is
initial={"":""}
form=ArticleModel(request.POST)
if form.has_changed():
data = {i: form.cleaned_data[i] for i in form.changed_data}
data.update({key: val for key, val in init_praram.items() if key not in form.changed_data})
use form.has_changed ,if form.fields is required you can use this method

How I added the initial to the form:
I read #Sergey Golovchenko answer.
So I just added it to the form in if request.method == 'POST':.
But that's not where you place it, if you want to see what value it got before posting the form.
You need to put it in the form where the else is.
Example here from views.py
def myForm(request):
kontext = {}
if request.method == 'POST':
# You might want to use clean_data instead of initial here. I found something on a stack overflow question, and you add clean data to the Forms.py, if you want to change the post data. https://stackoverflow.com/questions/36711229/django-forms-clean-data
form = myModelForm(request.POST, initial={'user': request.user})
if form.is_valid():
form.save()
return redirect('/')
else:
# you need to put initial here, if you want to see the value before you post it
form = myModelForm(initial={'user': request.user})
kontext['form'] = form
return render(request, 'app1/my_form.html', kontext)

Related

How To Update Specific Model Field From Django View Before Saving A Form

So, How can I update some Model Fields automatic, without the user having to input the values?
In Models:
class Url(models.Model):
long_url = models.CharField("Long Url",max_length=600)
short_url = models.CharField("Short Url",max_length=7)
visits = models.IntegerField("Site Visits",null=True)
creator = models.ForeignKey(CurtItUser,on_delete=models.CASCADE,null=True)
def __str__(self):
return self.short_url
In Views:
def home(request):
"""Main Page, Random Code Gen, Appendage Of New Data To The DB"""
global res,final_url
if request.method == 'POST':
form = UrlForm(request.POST)
if form.is_valid():
res = "".join(random.choices(string.ascii_uppercase,k=7))
final_url = f"127.0.0.1:8000/link/{res}"
form.save()
redirect(...)
else:
form = UrlForm
return render(...)
Sow how can for exapmle set from my view the value of short_url to final_url ???
You can get the data you need from the form.
you need to get the specific instance first, then you can use that instance to save values from the form.
And do not forget to save!
url_instance = get_object_or_404(Url, pk=pk)
url_instance.short_url = form.cleaned_data['short_url']
url_instance.long_url = form.cleaned_data['long_url']
url_instance.visits = form.cleaned_data['visits']
url_instance.save()
You can find more detailed infromations in the Django Documentation.

Setting an initial value in a Django Form

I have to setup an initial value in a form and somehow is not working, it is extremely strange as I have exactly the same code in another view, but in this case my approach is not working:
views.py
#login_required
def add_lead(request):
if request.method == 'POST':
lead_form = LeadsForm(request.POST)
if lead_form.is_valid():
lead_form.save()
messages.success(request, 'You have successfully added a new lead')
return HttpResponseRedirect(reverse('add_lead'))
else:
messages.error(request, 'Error updating your Form')
else:
user = {"agent":request.user}
lead_form = LeadsForm(request.POST or None, initial = user)
return render(request,
'account/add_lead.html',
{'lead_form': lead_form}
)
forms.py
class LeadsForm(forms.ModelForm):
class Meta:
model = Leads
fields = ('project_id','company','agent','point_of_contact','services','expected_licenses',
'expected_revenue','country', 'status', 'estimated_closing_date'
)
widgets = {'estimated_closing_date': DateInput(),
}
Essentially, the agent is the logged user, so I'm passing request.user as a variable, but I have not succeeded, which is very strange because I have that same logic in another form
Any help will be appreciated
If you want to make a form with a foreign key you can use ModelChoiceField. In your case you can use:
class LeadsForm(forms.ModelForm):
agent = forms.ModelChoiceField(queryset=User.objects.all())
class Meta:
model = Leads
fields = ('project_id','company','agent','point_of_contact','services','expected_licenses',
'expected_revenue','country', 'status', 'estimated_closing_date'
)
widgets = {'estimated_closing_date': DateInput(),
}
Then you can assign data with user_id in your form initial.

How to set the default value can shown on the table with Django?

I have already created a formClass as below:
class LyricForm(ModelForm):
class Meta:
model = Lyric
fields = ['title', 'body']
widgets = {
'body': Textarea(attrs = {'cols': 40, 'rows': 20 })
}
I have used it for create form which I don't want to any default value on that and it works well.
Now I want to inherit it as edit form, whose default value is its existing value like :
I referenced some relative questions in stackoverflow as below:
views.py
def update_lyric(request, pk):
lyric = get_object_or_404(Lyric, pk = pk)
form = LyricForm(request.POST, initial = {'title': lyric.title, 'body': lyric.body})
return render(request, 'update_lyric_page.html',{'pk':pk, 'form':form})
But it does not work. There is no any default value shown on the form. How can I do that? Thank you in advance!
Since you're using modelforms, you could use:
def update_lyric(request, pk):
lyric = get_object_or_404(Lyric, pk = pk)
form = LyricForm(request.POST, instance=lyric)
return render(request, 'update_lyric_page.html',{'pk':pk, 'form':form})

Django: how to loop through boolean fields and set all to false

So, I have a table called "order" that has a foreign key with the table "store". The order table has a boolean field set by default to false. When a new order is created, I need to loop through the boolean values associated with each individual store and set the other orders to false and the new order to true. Not sure how to create the for loop for that. First I tried to set it into the view, but maybe it can be put into the forms.py file? This my create code so far.
def create(request):
if request.POST:
form = OrderForm(request.POST)
if form.is_valid():
form.save()
return HttpResponseRedirect('/liquors/all')
else:
form = OrderForm()
args = {}
args.update(csrf(request))
args['form'] = form
return render_to_response('create_order.html', args)
Models provided upon request, you shouldn't need anything except the order model:
class Order(models.Model):
OrderID = models.AutoField(primary_key=True)
storeID = models.ForeignKey(Store)
DateCreated = models.DateField('Date Created', auto_now_add=True)
OrderName = models.CharField('Order Name', max_length=25 )
Active = models.BooleanField()
you must return render_to_response('create_order.html', args) one indentation back. so that validation form will not affected. you don't need to use csrf request if you are using render. I think there is no need to use OrderId in Order model, since it is automattically created. ie id
from django.shortcuts import render
from <appname>.models import Order,Store
def create(request):
if request.POST:
form = OrderForm(request.POST)
if form.is_valid():
#i just assume the storeid variable is exist in request.POST and it is ID.
store_data=Store.objects.get(id=request.POST['storeid'])
#here you might need to update the other orderform to false
Order.objects.filter(storeID=store_data).update(Active=False)
fo=Order(storeID=store_data,Active=True)
frm_order=OrderForm(request.POST,instance=fo)
frm_order.save()
return HttpResponseRedirect('/liquors/all')
else:
form = OrderForm()
return render(request,'create_order.html', {'form':form})
You can use the order object's meta object to loop through the fields. Ex.
for field in order._meta.fields():
if type(field) = django.db.models.fields.BooleanField:
setattr(order, field.name, True)

Django initial value of choicefield

I'm having a strange problem where I can't seem to set the initial value of one of the fields in my forms in django.
My model field is:
section = models.CharField(max_length=255, choices=(('Application', 'Application'),('Properly Made', 'Properly Made'), ('Changes Application', 'Changes Application'), ('Changes Approval', 'Changes Approval'), ('Changes Withdrawal', 'Changes Withdrawal'), ('Changes Extension', 'Changes Extension')))
My form code is:
class FeeChargeForm(forms.ModelForm):
class Meta:
model = FeeCharge
# exclude = [] # uncomment this line and specify any field to exclude it from the form
def __init__(self, *args, **kwargs):
super(FeeChargeForm, self).__init__(*args, **kwargs)
self.fields['received_date'] = forms.DateField(('%d/%m/%Y',), widget=forms.DateTimeInput(format='%d/%m/%Y', attrs={'class': 'date'}))
self.fields['comments'].widget.attrs['class']='html'
self.fields['infrastructure_comments'].widget.attrs['class']='html'
My view code is:
form = FeeChargeForm(request.POST or None)
form.fields['section'].initial = section
Where section is a url var passed to the function. I've tried:
form.fields['section'].initial = [(section,section)]
With no luck either :(
Any ideas what I'm doing wrong or is there a better way to set the default value (before a form submit) of this choice field from a url var?
Thanks in advance!
Update: It seems to be something to do with the URL variable.. If I use:
form.fields['section'].initial = "Changes Approval"
It works np.. If I HttpResponse(section) it's outputs correctly tho.
The problem is use request.POST and initial={'section': section_instance.id}) together. This happens because the values of request.POST always override the values of parameter initial, so we have to put it separated. My solution was to use this way.
In views.py:
if request.method == "POST":
form=FeeChargeForm(request.POST)
else:
form=FeeChargeForm()
In forms.py:
class FeeChargeForm(ModelForm):
section_instance = ... #get instance desired from Model
name= ModelChoiceField(queryset=OtherModel.objects.all(), initial={'section': section_instance.id})
---------- or ----------
In views.py:
if request.method == "POST":
form=FeeChargeForm(request.POST)
else:
section_instance = ... #get instance desired from Model
form=FeeChargeForm(initial={'section': section_instance.id})
In forms.py:
class FeeChargeForm(ModelForm):
name= ModelChoiceField(queryset=OtherModel.objects.all())
UPDATE
Try escaping your url. The following SO answer and article should be helpful:
How to percent-encode URL parameters in Python?
http://www.saltycrane.com/blog/2008/10/how-escape-percent-encode-url-python/
Try setting the initial value for that field as follows and see if that works:
form = FeeChargeForm(initial={'section': section})
I assume you're going to be doing a lot of other things when the user posts the form, so you could separate the POST form from the standard form using something like:
if request.method == 'POST':
form = FeeChargeForm(request.POST)
form = FeeChargeForm(initial={'section': section})

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