We Keep Coding

How can I implement the same widget that Django uses to ManyToMany fields in the admin page?

My models:
class Ingredient(models.Model):
BASE_UNIT_CHOICES = [("g", "Grams"), ("ml", "Mililiters")]
CURRENCY_CHOICES = [("USD", "US Dollars"), ("EUR", "Euro")]
ingredient_id = models.AutoField(primary_key=True)
name = models.CharField(max_length=200)
base_unit = models.CharField(max_length=2, choices=BASE_UNIT_CHOICES)
cost_per_base_unit = models.FloatField()
currency = models.CharField(
max_length=3, choices=CURRENCY_CHOICES, default="EUR")
def __str__(self):
return self.name
class RecipeIngredient(models.Model):
quantity = models.FloatField()
ingredient_id = models.ForeignKey(Ingredient, on_delete=models.CASCADE)
def __str__(self):
return f"{self.quantity} / {self.ingredient_id}"
class Recipe(models.Model):
recipe_id = models.AutoField(primary_key=True)
name = models.CharField(max_length=200)
ingredients = models.ManyToManyField(RecipeIngredient)
date_created = models.DateTimeField('Date Created')
def __str__(self):
return f"{self.name}, {self.ingredients}"
When I use the admin page, it has this + button that allows me to create new ingredient/quantity combinations
like this
But when I try to use it from a form in my code it looks like
this
Here is my form code:
class AddRecipeForm(forms.ModelForm):
class Meta:
model = Recipe
fields = ['name', 'ingredients', 'date_created']

You should write the 'widgets' for each field in you Form that need configuration.
Check the documentation 'Widgets in forms', or even, you can define your own Widgets.

Can't to add a data into MongoDB using djongo "Array Model Field"

I'm trying to add a data using "Array Model Field"(djongo) as shown Djongo Documentation(Array Model Field) or
from djongo import models
class Blog(models.Model):
name = models.CharField(max_length=100)
tagline = models.TextField()
class Meta:
abstract = True
class MetaData(models.Model):
pub_date = models.DateField()
mod_date = models.DateField()
n_pingbacks = models.IntegerField()
rating = models.IntegerField()
class Meta:
abstract = True
class Author(models.Model):
name = models.CharField(max_length=200)
email = models.EmailField()
class Meta:
abstract = True
def __str__(self):
return self.name
class Entry(models.Model):
blog = models.EmbeddedModelField(
model_container=Blog,
)
meta_data = models.EmbeddedModelField(
model_container=MetaData,
)
headline = models.CharField(max_length=255)
body_text = models.TextField()
authors = models.ArrayModelField(
model_container=Author,
)
n_comments = models.IntegerField()
def __str__(self):
return self.headline
Into admin.py I added for registration of model in admin panel
from django.contrib import admin
from .models import Entry
admin.site.register(Entry)
And when I try to add a data via http://localhost:8000/admin/ I have a MigrationError...
Where is my mistake? And what am I not understanding?

You should use models.ObjectIdField() on all models to avoid calling django migrations.
Example:
class Author(models.Model):
_id = models.ObjectIdField()
name = models.CharField(max_length=200)
email = models.EmailField()
class Meta:
abstract = True
def __str__(self):
return self.name
See more in Djongo Docs

I'm a stupid. Sry. I didn't 'makemigration' after update a model.
And so here's what I did to make it work:
1. After update a model I did 'python manage.py makemigrations' and that power on.

relationships in django 2 models.py

I want to define a relationship between Book and Member through Borrow in models.py
ER
But I don't know how to define the Borrow relationship.
In the Borrow table it must be determined which books have been borrowed by who and which books have been returned on which date. Should I use another table for this date field?
models.py
from django.contrib.auth.models import AbstractUser
from django.db import models
from django.utils.translation import gettext as _
class CategoryType(models.Model):
category_name = models.CharField(max_length=200)
def __str__(self):
return self.category_name
class Book(models.Model):
name = models.CharField(verbose_name="عنوان", max_length=128)
number_of_copy = models.IntegerField(default=0)
writer = models.CharField(max_length=64)
B_category = models.ForeignKey(CategoryType, on_delete=models.CASCADE)
class Meta:
ordering = ["B_category"]
def __str__(self):
return self.name
class Borrow(models.Model):
borrowed_from_date = models.DateField(_("borrow Date"), default=0)
borrowed_to_date = models.DateField(_("return Date"), default=3)
actual_return_date = models.DateField()
borrowed_by = models.ForeignKey(member, on_delete=models.CASCADE)
books = models.ManyToManyField(Book)
def __str__(self):
return self.id
class Member(AbstractUser):
pass
I think in the Member class I should have a field containing borrow_id, but how?

It seems to me that you need to use a ManyToMany relationship with a through model (this way you can store extra information for every row of the Borrow model)
...
class Borrow(models.Model):
borrowed_from_date = models.DateField(_("borrow Date"), default=0)
borrowed_to_date = models.DateField(_("return Date"), default=3)
actual_return_date = models.DateField()
borrowed_by = models.ForeignKey(Member, on_delete=models.CASCADE)
book = models.ForeignKey(Book)
def __str__(self):
return self.id
...
class Member(AbstractUser):
borrowed_books = models.ManyToManyField(Book, through='Borrow')
Maybe this link (https://docs.djangoproject.com/es/2.1/ref/models/fields/#django.db.models.ManyToManyField.through) could clarify it more.

How to show how many records in django databes I have?

I have a little problem. In my models.py file I have two classes:
class Categories and class Websites.
In Categories by the admin panel I added many records of categories. How to show in html file for example : how many webstites were added in the category 'Company' or in the another categories?

Here is my models.py
from django.db import models
from django.utils import timezone
class Kategorie(models.Model):
glowna = models.CharField(max_length=150, verbose_name='Kategoria')
class Meta:
verbose_name='Kategoria'
verbose_name_plural='Kategorie'
def __str__(self):
return self.glowna
class Witryna(models.Model):
nazwa = models.CharField(default="", max_length=150, verbose_name = 'Nazwa strony')
adres_www = models.CharField(max_length=70, verbose_name='Adres www')
slug = models.SlugField(max_length=250, verbose_name='Przyjazny adres url')
email = models.CharField(max_length=100, verbose_name='Adres e-mail')
text = models.TextField(max_length=3000, verbose_name='Opis strony')
kategoria = models.ForeignKey(Kategorie, verbose_name='Kategoria')
data_publikacji = models.DateTimeField(blank=True, null=True, verbose_name='Data publikacji')
class Meta:
verbose_name='Strona www'
verbose_name_plural = 'Strony www'
def publikacja(self):
self.data_publikacji=timezone.now()
self.save()
def __str__(self):
return self.nazwa

Python's unicode

I have the following:
from django.db import models
class Category(models.Model):
name = models.CharField(max_length=200)
def _unicode_(self):
return self.name
class Item(models.Model):
category = models.ForeignKey(Category)
dateadded = models.DateTimeField('date added')
name = models.CharField(max_length=200)
description = models.TextField()
quantity = models.IntegerField()
My problem is that def _unicode_(self) isn't working. Any ideas?

you should use def __unicode__