In django admin i had one model named 'student', here it has three fields, NAME, ROLL NO. & SUBJECT.
in models.py:
from django.db import models
class Student(models.Model):
Name = models.CharField(max_length=255, blank = False)
Roll_No = models.CharField(max_length=10, blank = False)
Subject = models.CharField(max_length=20, blank = False)
def __str__(self):
return self.Name
now i want this SUBJECT field to be Dynamic, like there will be "+" sign besides the SUBJECT field, by clicking that one more SUBJECT field will be added right after it and so on, but maximum 10 SUBJECT fields can be added like that.
You can update the existing value when doing the subject addition from views.
Like for example in views:
student = Student.objects.get(id=1)
student.Subject += "New_Subject_Name"
student.save() # this will update only
Add other conditions/check for the existing subject and check for 10 subjects accordingly.
Related
Here is the model
class Student(models.Model):
"""Student info"""
id = models.CharField( max_length=7,primary_key=True)
name = models.CharField(_('name'),max_length=8, default=""); # help_text will locate after the field
address = models.CharField(_('address'),max_length=30,blank=True,default="") #blank true means the
GENDER_CHOICES = [("M", _("male")),("F",_("female"))]
student_number = models.CharField(max_length=10,blank=True)
gender = models.CharField(_("gender"),max_length=6, choices = GENDER_CHOICES, default="M");
I user shell to create two users as below:
But the queryset number didn't increase although I created two users.
#I hate Django. Q = Q
You are using a custom id field as model id and you put it as Char, so you should add this id also when you want to save an object
But it is not a good idea, if you want to use custom id use it in this way
id = models.AutoField(primary_key=True)
I have the following models:
# Get or create a 'Not selected' category
def get_placeholder_categoy():
category, _ = ListingCategories.objects.get_or_create(category='Not selected')
return category
# Get default's category ID
def get_placeholder_category_id():
return get_placeholder_categoy().id
class ListingCategories(models.Model):
category = models.CharField(max_length=128, unique=True)
def __str__(self):
return f'{self.category}'
class Listing(models.Model):
title = models.CharField(max_length=256)
seller = models.ForeignKey(User, on_delete=models.CASCADE, related_name='listings')
description = models.TextField(max_length=5120, blank=True)
img_url = models.URLField(default='https://media.istockphoto.com/vectors/no-image-available-picture-coming-soon-missing-photo-image-vector-id1379257950?b=1&k=20&m=1379257950&s=170667a&w=0&h=RyBlzT5Jt2U87CNkopCku3Use3c_3bsKS3yj6InGx1I=')
category = models.ForeignKey(ListingCategories, on_delete=models.CASCADE, default=get_placeholder_category_id, related_name='listings')
creation_date = models.DateTimeField()
base_price = models.DecimalField(max_digits=10, decimal_places=2, validators=[
MinValueValidator(0.01),
MaxValueValidator(99999999.99)
])
With these, I have the following form:
class ListingForm(ModelForm):
class Meta:
model = Listing
exclude = ['seller', 'creation_date']
widgets = {
'title': TextInput(attrs=base_html_classes),
'description': Textarea(attrs=base_html_classes),
'img_url': URLInput(attrs=base_html_classes),
'category': Select(attrs=base_html_classes),
'base_price': NumberInput(attrs=base_html_classes)
}
One of the available categories I have is "Not selected", since I want to allow that if at some point a category were to be removed, items can be reassigned to that one, however, when rendering the form, I will do some validation on the view function to prevent it from being submitted if the "not selected" category is sent with the form.
Because of this, I want the HTML form on the template to assign the 'disabled' attribute to the option corresponding to that category, however, I have been searching for a couple of days now without finding anything that I was able to understand to the point where I could try it.
Ideally, another thing I'd like to achieve is to be able to modify the order of the rendered options on the form so that I can move to the top 'not selected' regardless of its primary key within the model.
I am aware I can just create a form instead of a model form, or just modify the template so I manually specify how to render the form itself, but I do feel like there is a simple fix to this either on the model or on the model form that I am just not finding yet.
Thanks in advance!
I would suggest you use (in model definition)
class Listing(models.Model):
..
category = model.ForeignKey(ListingCategories, on_delete=models.SET_NULL, null=True, related_name='listings')
..
and optionally in form definition
class ListingForm(ModelForm):
category = forms.ModelChoiceField(ListingCategories, empty_label='Not Selected')
..
While rendering model form, a required attribute will be automatically added, and in form validating, it is also required. It is only in database validation that the field can be left NULL
I am writing a form to let a user enter a purchase from the template. A couple things need to happen:
the purchase goes to populate a row in the replenishment table
some fields of the replenishment table get updated based on what the user has input
here is what my model look like:
class replenishment(models.Model):
Id = models.CharField(max_length=100, primary_key=True, verbose_name= 'references')
Name = models.CharField(max_length=200)
Quantity = models.FloatField(default=0)
NetAmount = models.FloatField(default=0)
SupplierID = models.CharField(max_length=200)
Supplier = models.CharField(max_length=200)
SellPrice = models.FloatField(default=0)
StockOnOrder = models.FloatField(default=0)
StockOnHand = models.FloatField(default=0)
def __str__(self):
return self.reference
and the form:
class ProcurementOperationRecord(forms.Form)
Id = forms.CharField(required=True)
Quantity = forms.FloatField(required=True)
NetAmount = forms.FloatField(required=True)
Supplier = forms.CharField(required=True)
SellPrice = forms.FloatField(required=True)
I have no clue how to let the user input the values in form and automatically add Quantity to StockOnOrder as well as automatically recognize the SupplierID based on Supplier. At this point I don't know where to start really. At least, is it possible to achieve what I try to do?
First, I've changed some things around and added some comments to what and why I did them.
# models/classes in python are singular AND camel cased (99.9%)
class Supplier(models.Model):
...
# models/classes in python are singular AND camel cased (99.9%)
class Replenishment(models.Model):
# attributes are normally lower case and snake cased (99.9%)
# try not to do this, a CharField??, unless you're using a guid? if so use UUIDField()
# https://docs.djangoproject.com/en/3.1/ref/models/fields/#uuidfield
id = models.CharField(db_column='Id', max_length=100, primary_key=True, verbose_name='references')
name = models.CharField(db_column='Name', max_length=200)
quantity = models.FloatField(db_column='Quantity', default=0)
net_amount = models.FloatField(db_column='NetAmount', default=0)
# deleted your field "Supplier" -- with this change you can join to the other table and get what you need without having to duplicate anything
supplier = models.ForeignKey(Supplier, db_column='SupplierID')
sell_price = models.DecimalField(db_column='SellPrice', default=0, max_digits=6, decimal_places=2) # You're asking for trouble if you keep this as FloatField
stock_on_order = models.IntegerField(db_column='StockOnOrder', default=0) # how can you have ordered a .5 for your stock? changed to IntegerField
stock_on_hand = models.IntegerField(db_column='StockOnHand', default=0) # how can you have a .5 of your stock? changed to IntegerField
class Meta:
db_table = 'replenishment' # try not to do this either.. let django come up with the name.. unless you're using an existing database/table?
...
# models/classes in python are singular AND camel cased (99.9%)
# django has a standard that they normally postfix forms with "Form" at the end of the class (no matter if it's a ModelForm or regular Form)
class ProcurementOperationRecordForm(forms.ModelForm)
class Meta:
model = Replenishment
fields = ('id', 'quantity', 'net_amount', 'supplier', 'sell_price')
# I would remove the "id", the client shouldn't care or know about it..
Now to create and update. (This would live inside a view)
# creating?
form = ProcurementOperationRecordForm(data=request.POST)
if form.is_valid():
form.save()
return redirect(..) or render(..)
# updating?
replenishment = Replenishment.objects.get(id='...something')
form = ProcurementOperationRecordForm(data=request.POST, instance=replenishment)
if form.is_valid():
form.save()
return redirect(..) or render(..)
This is just a general idea. You can try something like this.
First get the user input values of quantity and supplier like this from the valid form.
quantity = form.cleaned_data.get('quantity')
supplier = form.cleaned_data.get('supplier')
Then you can update your replenishment model
replenishment.objects.filter(Supplier=supplier).update(StockOnOrder=quantity)
I am using django 1.9 , i have following model which have two foreing fields,
models.py
class Mobile(models.Model):
name = models.CharField(max_length=100)
product = models.ForeignKey(Product)
owner = model.ForeignKey(Customer)
now i want to build a admin interface for Mobile model where i want to provide list display for both product and owner foreign fields,that is, the list display will show one of the field of that foreign fields and also want to change the column name,i have tried so but its not working at all
admin.py
class MobileModelAdmin(admin.ModelAdmin):
list_display = ('name','product', 'owner')
def related_product(self, obj):
return obj.product.name
related_product.short_description = 'product name'
def related_owner(self, obj):
return obj.owner.name
related_owner.short_description = 'owner name'
admin.site.register(Mobile, MobileModelAdmin)
but neither its changing the column name nor showing the related value.
I think you have to do
list_display = ('name','related_product', 'related_owner') #means method name what you are given.
I Would like to get all the Teachers that have at least 1 subject. Currently I'm using...
user = users.objects.all().order_by('-karma')[:100]
Because people who does not have any subjects related is a Student.
Here is my models.py
class subjects(models.Model):
id_user = models.IntegerField(db_column='ID_user') # Field name made lowercase.
s = models.CharField(max_length=90)
def __unicode__(self):
return self.s
class Meta:
db_table = 'subjects'
class users(models.Model):
email = models.EmailField(max_length=160)
nick = models.CharField(unique=True, max_length=60)
karma = models.IntegerField(max_length=11)
pass_field = models.CharField(db_column='pass', max_length=160)
One option is to do this in two steps:
get id_user list from subjects model with the help of values_list():
user_ids = subjects.objects.values_list('id_user', flat=True).distinct()
get all users by the list of id_users using __in:
print users.objects.filter(pk__in=user_ids)
Also, since models are not related, you can make a raw query that would do the same in one go.