Populate Django ManyToManyField Options Based on Other Field in Admin - python

I am having problems filtering options for a ManyToManyField on the Django Admin Add screen based on input to another field on the same form. I am new to Django and have been unable to use any of the generic fixes described elsewhere because they are all slightly different than my situation. Here is my situation:
I have three models in my project: Class, Student, and AttendanceRecord. In the Django Admin, when adding an attendance record, I would like to change the options for the field Absent_Students based on the selection made for the field Associated_Class. So, for example, if Associated_Class "CS 450" is selected, the options for Absent_Students should change to only students whose class_list includes CS 450.
Here are my models:
from __future__ import unicode_literals
from django.db import models
from django.contrib.auth.models import User
from django.utils.encoding import python_2_unicode_compatible
import random, string
# Create your models here.
#This is the model for a student
#python_2_unicode_compatible
class Student(models.Model):
pass
Student_First_Name = models.CharField(max_length=200)
Student_Last_Name = models.CharField(max_length=200)
Student_ID_Number = models.CharField(max_length=200)
Student_Class = models.ForeignKey('Class', null=True)
def __str__(self):
return self.Student_Last_Name + ',' + self.Student_First_Name
# This is the model for a class
#python_2_unicode_compatible
class Class(models.Model):
class Meta:
verbose_name_plural = "Classes"
Class_Name = models.CharField(max_length=200)
Student_List = models.ManyToManyField('Student', related_name='class_list')
Professor = models.ForeignKey(User,null=True)
AddCode = models.IntegerField
pass
def __str__(self):
return self.Class_Name
def getName(self):
return self.Class_Name
def getProfessor(self):
return self.Professor.id
def getProf(self):
return self.Professor
def getStudents(self):
return self.Student_List
#This is the model for attendance records
class AttendanceRecord(models.Model):
class Meta:
verbose_name = "Attendance Record"
Associated_Class = models.ForeignKey(Class, on_delete=models.CASCADE, related_name='Attendance_Records')
Date = models.DateField()
Absent_Students = models.ManyToManyField('Student', blank=True)
Present_Students = models.ManyToManyField('Student', related_name='a')
def get_associated_class_id(self):
return self.Associated_Class
def __str__(self):
return self.Associated_Class.__str__() + ' on date ' + self.Date.__str__(self)
I have tried doing this by editing the AttendanceRecordAdminForm class and AttendanceRecordAdmin class. My problem is that when setting the self.fields['Absent_Students].queryset I do not know how to access the currently selected Associated_Class on the form. I keep getting an error that "AttendanceRecord has no Associated_Class". Here are those classes just discussed in their entirety:
class AttendanceRecordAdminForm(forms.ModelForm):
class Meta:
model = AttendanceRecord
fields = '__all__'
def __init__(self, *args, **kwargs):
super(AttendanceRecordAdminForm, self).__init__(*args, **kwargs)
instance = kwargs.get('instance', None)
self.fields['Absent_Students'].queryset = Student.objects.filter(class_list__id=self.instance.get_associated_class_id())
self.fields['Present_Students'].queryset = Student.objects.filter(class_list__id=1)
class AttendanceRecordAdmin(admin.ModelAdmin):
form = AttendanceRecordAdminForm
filter_horizontal = ('Absent_Students', 'Present_Students',)
Basically, I am looking for a way to access the currently entered Associated_Class on the admin form so I can properly filter the queryset.

After hours more of online searching I finally found what I needed. A chained ManyToMany from the smart_select app makes this very easy. This link: How to use django-smart-select describes the install process and also links to the documentation for using it once it is installed. Hopefully this helps some others as well.

Related

Django , how to show 'secondary property' of parent in TabularInline

I try to do tabular inline admin.
In the child tab, if we include a ForeignKey field, it will show the str property of that foreign model.
But how to also show another property of that foreign model?
Here is my models.py
class RawMaterial(models.Model):
name = models.CharField(max_length=15)
ubuy = models.CharField(max_length=5)
usell = models.CharField(max_length=5)
uconv = models.DecimalField(max_digits = 5,decimal_places=2)
def __str__(self):
return self.name
class Coctail(models.Model):
name = models.CharField(max_length=20)
def __str__(self):
return self.name
class Ingredient(models.Model):
coctail = models.ForeignKey(Coctail,
related_name='ingredient',
on_delete=models.CASCADE)
rawmaterial = models.ForeignKey(RawMaterial,
related_name='ingredient',
on_delete=models.CASCADE)
qty = models.DecimalField(max_digits = 5,decimal_places=2)
def __str__(self):
return self.rawmaterial
def rawusell(self):
return self.rawmaterial.usell
rawusell.short_description = 'UOM'
Here is my admin.py
from django.contrib import admin
# Register your models here.
from .models import *
admin.site.register(RawMaterial)
class IngredientInline(admin.TabularInline):
model = Ingredient
list_display = ('rawmaterial', 'qty', 'rawusell')
class CoctailAdmin(admin.ModelAdmin):
inlines = [IngredientInline]
admin.site.register(Coctail, CoctailAdmin)
and here what I got
My question is : How to show rawmaterial.usell in Ingredient tab?
Sincerely
-bino-
You can show the rawmaterial.usell field in the ingredient tab but it will not be editable. Since, any field can only be editable if they are a field of that model (Without using any custom form and logic).
So, if you want rawmaterial.usell to be editable, you will have to make a rawmaterial admin
You can show the rawmaterial.usell in IngredientInline by doing this.
class IngredientInline(admin.TabularInline):
model = Ingredient
readonly_fields = ('rawusell', )
list_display = ('rawmaterial', 'qty', 'rawusell')
def rawusell(self, obj):
return obj.rawmaterial.usell
This will start showing usell in the inline admin.

Stuck on linking ManytoMany relationships with Modelform

I'm pretty new to Django and I am working on a project that currently requires the following:
I have two basic structures: a Project model and a TeamMember model- both related to each other through a ManytoMany relationship. Then I have an TMAssigned 'through' class. The team member will have many projects assigned to it over time.
I have a ModelFrom which creates a Project model through the creation of the form.
My question is, How do I link the team member to the newly created project upon the submission of the form?
Here is a bit of my model & form code:
TeamMember
class TeamMember(models.Model):
firstname = models.CharField(max_length=100, default= "First Name")
lastname = models.CharField(max_length=100, default= "Last Name")
fullname = models.CharField(max_length=100, default= "Full Name")
email = models.EmailField(max_length=254)
cellphone = PhoneNumberField(null=False, blank=False, unique=True)
numberofcases = models.IntegerField(max_length=10000, default=0)
#property
def fullnamefunc(self):
fullname = "{} {}".format(self.firstname, self.lastname)
return fullname
def __str__(self):
return self.fullname
Project
class Project(models.Model):
pursuitname = models.CharField(max_length=500)
datecreated = models.DateTimeField(auto_now=True)
bdmember = models.ManyToManyField('team.TeamMember')
Views.py
class bdFormView(TemplateView):
template_name = os.path.join(BASE_DIR, "templates/masterform/bdform.html")
def get(self,request):
form = bdForm()
return render (request, self.template_name, {'form': form})
def post(self, request):
form = bdForm(request.POST)
if form.is_valid():
print("form is valid")
project = form.save(commit=False)
project.save()
text = form.cleaned_data['briefcard']
Form.py
class bdForm(forms.ModelForm):
bdmemberlist = TeamMember.objects.all().order_by('lastname')
pursuitname = forms.CharField()
bdmember = forms.ModelChoiceField(queryset= bdmemberlist)
addbdteam = forms.ModelMultipleChoiceField(
queryset=TeamMember.objects.all().order_by('lastname'), widget=Select2MultipleWidget, required=False)
class Meta:
model = Project
fields = ['pursuitname','addbdteam','bdmember',]
def __init__(self, *args, **kwargs):
if kwargs.get('instance'):
initial = kwargs.setdefault('initial', {})
initial['projects'] = [t.pk for t in
kwargs['instance'].project_set.all()]
forms.ModelForm.__init__(self, *args, **kwargs)
def save(self, commit=True):
instance = forms.ModelForm.save(self, False)
old_save_m2m = self.save_m2m
def save_m2m():
old_save_m2m()
for project in self.cleaned_data['bdmember']:
instance.teammember_set.add(project)
Thanks in advance!!
Edit- after doing some more research, I've removed the "Through" model from the script and am trying to rely on the form.py save method to do the join. However, when I do this- the two are still not linking up properly.
Since only your admin (superusers?) will log in, you can start off by using the in-built Django Admin.
I would recommend this for you, at least for now, because you're a beginner and the Admin Form is stunningly simple to use. Then, you can create a custom form later on when you're more comfortable. :-)
With this in mind, you can try eliminating the 'through' table (you may need to reset your migrations), and try this.
Admin.py
from django.contrib import admin
from .models import TeamMember, TMAssigned, Project,
TeamMembersInLine(admin.TabularInline):
model = TeamMember
extra = 1
#admin.register(Project):
class ProjectAdmin(admin.ModelAdmin):
list_display = ('pursuitname', 'bdmember ', 'datecreated')
inlines = [TeamMembersInLine]
Here's another answer that delves into the through table. It was asked by someone in your situation and the answer is relevant too.

Django model reference and manipulation

I have the following models in Django that have a structure as follows:
class Office_Accounts(models.Model):
accountid = models.EmailField(max_length=200, unique=True)
validtill = models.DateField(default=datetime.now)
limit = models.CharField(max_length=2)
class Device(models.Model):
device_type = models.ForeignKey(DeviceType,to_field='device_type')
serial_number = models.CharField(max_length=200,unique=True)
in_use_by = models.ForeignKey(User,to_field='username')
brand = models.CharField(max_length=200,default="-", null=False)
model = models.CharField(max_length=200,default="-", null=False)
type_number = models.CharField(max_length=200,blank=True,null=True, default = None)
mac_address = models.CharField(max_length=200,blank=True,null=True, default = None)
invoice = models.FileField(upload_to='Device_Invoice', null=True, blank = True)
msofficeaccount = models.ForeignKey(Office_Accounts, to_field="accountid")
class Meta:
verbose_name_plural = "Devices"
def full_name(self):
return self.device_type + self.serial_number + self.brand
I will display both of the models in admin.py.
Now, I want to display the count of each accountid present in the field "msofficeaccount" (present in Device Models) in my admin page of Office_Accounts model. For an example if xyz#abc.com appears in 10 rows of msofficeaccount field then, the count should be displayed as 10 in Office_Accounts admin page. Can anyone please guide me how should I approach this problem to solve it?
You could add a method to your admin class that returns the count of related devices for each office_account, but that would be very inefficient. Instead you can override get_queryset to annotate the count from a database aggregation function:
from django.db.models import Count
class Office_AccountsAdmin(admin.ModelAdmin):
list_display = (..., 'device_count')
...
def get_queryset(self, request):
qs = super().get_queryset(request)
return qs.annotate(device_count=Count('device'))
(On a minor note, Python style is always to use CamelCase for class names, and Django style is to use singular model names, so your model should really be called OfficeAccount.)

Is it possible to save the primary key value of more than one fields of a model into an another model's single 'field' using foreign key relation?

models.py:
import datetime
from django.db import models
from pygments.lexers import get_all_lexers
LEXERS = [item for item in get_all_lexers() if item[1]]
class Classname(models.Model):
class_name = models.CharField(max_length=8)
def __str__(self):
return self.class_name
class Sectionname(models.Model):
class_name = models.ForeignKey(Classname)
section_name = models.CharField(max_length=1, default='A')
def __str__(self):
return self.section_name
class Teachername(models.Model):
field = """ I want to define here a foreign key field(inherited from Sectionname model)which saves the primary key value of row corresponding to two fields (class_name, section_name) above."""
teachname = models.CharField(max_length=50, verbose_name='teacher Name')
def __str__(self):
return self.teachname
class Attendancename(models.Model):
teacher_name = models.ForeignKey(Teachername)
date = models.DateField('Date')
intime = models.TimeField('IN-TIME')
outtime = models.TimeField('OUT-TIME')
def hours_conversion(self):
tdelta = (datetime.datetime.combine(datetime.date.today(),self.outtime) - datetime.datetime.combine(datetime.date.today(),self.intime))
hours, minutes = tdelta.seconds//3600, (tdelta.seconds//60)%60
return '{0}hrs {1}mins'.format(hours, minutes)
def __str__(self):
return "%s" %self.teacher_name
forms.py:
from django import forms
from django.forms import ModelForm
from .models import Classname, Sectionname, Teachername, Attendancename
class ClassnameForm(ModelForm):
class_name = forms.CharField(max_length=8)
class Meta:
model = Classname
fields = ('class_name',)
class SectionnameForm(ModelForm):
class_name = forms.ModelChoiceField(queryset=Classname.objects.all())
class Meta:
model = Sectionname
fields = ('section_name', 'class_name',)
class TeachernameForm(ModelForm):
field = """ Here I also want to do the same thing, I tried to make a form field, which shows value of both 'section_name' and 'class_name' from above model but only saves the value of corresponding row's primary key."""
class Meta:
model = Teachername
fields = ('classname', 'secname', 'teachname',)
class AttendancenameForm(ModelForm):
teacher_name = forms.ModelChoiceField(queryset=Teachername.objects.all())
class Meta:
model = Attendancename
fields = ('teacher_name', 'date', 'intime', 'outtime',)
I'm trying to save the 'pk' value of Sectionname model fields('calss_name', 'section_name') into Terachername model's single 'field', I also want to show the both the values to user using form field 'field', but behined the scenes only primary key values needs to be saved.
Is it possible to do so? If it is then how can I implement it in my app?
Please! provide your suggestions....
Thanks! in advance.....
You cannot store two foreign keys to two different tables in a single models.ForeignKey field, and it really wouldn't make any sense (if the reason is not obvious to you then you should learn more about relational model).
But anyway: since a Sectionname belongs to one single Classname, you don't need anything else than the Sectionname pk to get the related Classname:
class Teachername(models.Model):
sectionname = models.ForeignKey(Sectionname)
teachname = models.CharField(max_length=50, verbose_name='teacher Name')
def __str__(self):
return self.teachname
teacher = Teachername.objects.get(pk=XXX)
print teacher, teacher.sectionname, teacher.sectionname.classname
Or if a teacher is supposed to teach more than one section:
class Teachername(models.Model):
sectionnames = models.ManyToMany(Sectionname)
teachname = models.CharField(max_length=50, verbose_name='teacher Name')
def __str__(self):
return self.teachname
teacher = Teachername.objects.get(pk=XXX)
for sectionname in teacher.sectionnames.all():
print teacher, sectionname.classname

Django auth group model m2m

Recently, I have been working in a generic inscription system to help students to register in a class or a lab. But I have problems with the logic of ManyToManyField in the Lab class.
from django.db import models
from django.contrib.auth.models import User
class Day(models.Model):
name = models.CharField(max_length=20, primary_key=True)
def __unicode__(self):
return u"%s" % self.name
class LabName(models.Model):
lab_name = models.CharField(max_length=50, primary_key=True)
class Meta:
verbose_name_plural = 'LabNames'
def __unicode__(self):
return u'%s' % self.lab_name
class Lab(models.Model):
name = models.ForeignKey(LabName)
start_hour = models.TimeField()
length = models.IntegerField(help_text="Given in minutes")
classDays = models.ManyToManyField(Day)
start_date = models.DateField()
finish_date = models.DateField()
max_cap = models.SmallIntegerField(help_text="Maximun number of students")
teacher = models.ForeignKey(User, related_name="Teachers")
students = models.ManyToManyField(User)
class Meta:
verbose_name_plural = 'Labs'
def __unicode__(self):
return u"%s %s" % (self.id, self.name)
I would prefer to associate an specific Group (django.contrib.auth.models.Group) called 'Students' rather than all the users or at least filter and/or validate this field to just add and view students and also do the same with the teacher field.
Update 1: I just noticed that maybe I could filter those users who are in a certain group using the optional parameter limit_choices_to.
The question is:
How can I use the limit_choices_to parameter to show only those users who are in the 'Students' group or the 'Teachers' group?
Ah, see that's MUCH clearer.
I would re-write {'id__in' : Group.objects.all().get(name='Teachers').user_set.all()}
to:
{'groups__name' : 'Teachers' }
Also, if you would like to keep your admin functionality separated from your models more (did you know Admin was originally completely in the models?), you can use formfield_for_foreignkey which is certainly a nice way to keep your models separated from admin junk.
class MyModelAdmin(admin.ModelAdmin):
def formfield_for_foreignkey(self, db_field, request, **kwargs):
if db_field.name == "teacher":
kwargs["queryset"] = User.objects.filter(groups__name='Teacher')
if db_field.name == "students":
kwargs["queryset"] = User.objects.filter(groups__name='Student')
return super(MyModelAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)

Categories

Resources