I created two models:
class Country(models.Model):
name = models.CharField(verbose_name="Name of country", max_length=100, default="Australia")
number = models.IntegerField(verbose_name="number of country", default="1")
def __unicode__(self):
return self.name
class World(models.Model):
country = models.ManyToManyField(Country)
name = models.CharField(verbose_name="New Map", max_length=100)
def __unicode__(self):
return self.name
I want to give user possibility to create new world on site, but during creating he can't uncheck any object from a list (every object must be checked but he can't see them).
I created a form.py:
class WorldForm(forms.ModelForm):
country = forms.ModelMultipleChoiceField(queryset = Country.objects.all(), widget=forms.CheckboxSelectMultiple())
class Meta:
model = World
fields = ('name',)
But this code gives user possibility to choose objects and uncheck some. How to change it?
The best idea for me is when user creates his "world" - he can only type a name of world and he didn't see names of countries but every object "Country" will be includes in his "world" . Is that possible? How can i change code in forms to do something like this?
I think we could achieve that by overriding the ModelForm.save() method:
class WorldForm(forms.ModelForm):
class Meta:
model = World
fields = ('name',)
def save(self, commit=True):
super(WorldForm, self).save(commit=False)
is_new = not self.instance.pk
self.instance.save()
if is_new:
# It's a new world. Fill it with countries!
self.instance.country.add(*Country.objects.all())
else:
self._save_m2m()
return self.instance
Related
I can't find the mistake here. I saw some similar questions but still can't fix it.
here is my models.py
class Department(models.Model):
name = models.CharField(max_length=100)
class CustomUser(AbstractUser):
department = models.ManyToManyField(Department, blank=True)
class Student(models.Model):
user = models.OneToOneField(CustomUser, on_delete=models.CASCADE, primary_key=True)
department = models.ManyToManyField(Department, blank=True)
forms.py
class StudentRegisterForm(UserCreationForm):
class Meta(UserCreationForm):
model = CustomUser
fields = ['department', ..]
widgets = {'department': forms.CheckboxSelectMultiple()}
def __init__(self, *args, **kwargs):
super(StudentRegisterForm, self).__init__(*args, **kwargs)
self.fields['department'].required = True
def clean_department(self):
value = self.cleaned_data.get('department')
if len(value) > 1:
raise forms.ValidationError("You can't select more than one department!")
return value
def save(self, commit=True):
user = super().save(commit=False)
user.save()
student = Student.objects.create(user=user)
student.department.add(self.cleaned_data.get('department')) <-- got error on this line
return (user, student)
When the CustomUser object is created, the Student object will also be created within save method. But for some reasons it gave me an error
TypeError: Field 'id' expected a number but got <QuerySet [<Department: GEE>]>.
Noticed that the Department objects were created within admin panel and also the department field within the Student model works just fine if I create it inside admin panel.
I fixed it by adding * into the add method like this
student.department.add(*self.cleaned_data.get('department'))
I'm playing around in Django, and wondering if there is a way to loop through instances of two different models I have created?
/ models.py:
class Tran(models.Model):
name = models.CharField(max_length=300)
description = models.CharField(max_length=2000)
type = models.ForeignKey(TransactionType)
def __str__(self):
return self.name
class DocLink(models.Model):
trann = models.ForeignKey(Transaction)
t_link = models.CharField(max_length=2000)
t_display = models.CharField(max_length=1000)
p_display = models.CharField(max_length=300)
p_link = models.CharField(max_length=2000)
def __str__(self):
return self.link
What I want to do:
Look through each of the Tran instances and create a default value for the links/displays in the DocLink table instead of doing it manually.
Is there anyway I can be pointed in the right direction?
If you want to set links/displays default value in DocLink instance based on trann field you can override model's save method.
For example following code shows how to set t_link if it doesn't have a value:
class DocLink(models.Model):
trann = models.ForeignKey(Transaction)
t_link = models.CharField(max_length=2000)
t_display = models.CharField(max_length=1000)
p_display = models.CharField(max_length=300)
p_link = models.CharField(max_length=2000)
def __str__(self):
return self.link
def save(self, *args, **kwargs):
if not self.t_link:
pass # TODO set self.t_link based on trann
super(DocLink, self).save(*args, **kwargs)
Also you can change model's trann field to:
trann = models.ForeignKey(Transaction, related_name="doclinks")
And then access to all DocLinks of a Tran with:
# t is an instance of Tran class
t.doclinks.all()
So you can loop through this list and do what you want.
Hi there pretty new to django but considering the below models, with their relationships, how do I create a read only field for the object that is a reference to a field in another class? I've looked for a while on stackoverflow, but not sure what kind of model reference that would be.
The basic logic for this being:
I have this server rack that sites on a floor in a server room, and I'm associating it to a rack position, and row to manage power consumption and other goodies. Just for my end-user's reference I want a read only field to show them what row this rack lives in, and its derived from the rack position. I'd been fiddling around with creating a method to look it up, but can't seem to figure out the syntax or find something related on the django admin pages.
Any ideas would be super appreciated, I really could use the help as I've been staring through docs forever, and can't seem to find a relevant model reference for this.
class rack(models.Model):
class Meta:
verbose_name = "Rack"
verbose_name_plural = "Racks"
def __unicode__(self):
return str(self.position)
def row(self, obj):
return self.position.row
position = models.OneToOneField("rackposition")
row = row(position.row.row)
asstag = models.CharField("Asset Tag", max_length=200, unique=True)
rackunits = models.IntegerField("Rack Units")
class rackposition(models.Model):
class Meta:
verbose_name = "Rack Position"
verbose_name_plural = "Rack Positions"
def __unicode__(self):
return str(self.position)
position = models.CharField("Position", max_length=35, primary_key=True)
row = models.ForeignKey("row")
class row(models.Model):
class Meta:
verbose_name = "Row"
verbose_name_plural = "Rows"
def __unicode__(self):
return str(self.row) + "." + str(self.suite)
row = models.CharField("Row ID", max_length=200, unique=True)
suite = models.ForeignKey(suite, blank=False)
power_budget = models.IntegerField("Power Budget")
power_volt = models.IntegerField("Power Voltage")
dual_bus = models.BooleanField("Dual Bus", default=False)
You don't need a method. Assuming you have a rack instance called my_rack, you can get its row with my_rack.position.row.
Note, you should really follow PEP8 and use CamelCase for your class names.
If you want to see it as a readonly field in the admin, you will need to define a method either on the model or on the ModelAdmin class. For example:
class RackAdmin(admin.ModelAdmin):
model = Rack
readonly_fields = ('row',)
def row(self, obj):
return obj.position.row
taking my initial lessons with django ModelForm ,I wanted to give the user ,ability to edit an entry in a blog.The BlogEntry has a date,postedTime, title and content.I want to show the user an editform which shows all these fields,but with only title and content as editable. The date and postedTime should be shown as uneditable.
class BlogEntry(models.Model):
title = models.CharField(unique=True,max_length=50)
description = models.TextField(blank=True)
date = models.DateField(default=datetime.date.today)
postedTime = models.TimeField(null=True)
...
For adding an entry ,I use a ModelForm in the normal way..
class BlogEntryAddForm(ModelForm):
class Meta:
model = BlogEntry
...
But how do I create the edit form?I want it to show the date,postedTime as uneditable (but still show them on the form) and let the user edit the title and description.
if I use,exclude in class Meta for date and postedTime,that will cause them not to appear on the form.So,how can I show them as uneditable?
class BlogEntryEditForm(ModelForm):
class Meta:
model = BlogEntry
...?...
In the form object, declare the attribute of the field as readonly:
form.fields['field'].widget.attrs['readonly'] = True
Is date field represent a date when the entry first created or when it was modified last time? If first then use auto_now_add option else use auto_now. That is:
date = models.DateField(auto_now_add=True)
will set date to now when entry will be created.
auto_now_add makes field uneditable. For other cases use editable option to make any field uneditable. For example
postedDate = models.TimeField(null=True, editable=False)
Also, likely you will add posted boolean field to Entry model, so it is convinient to set auto_now on postedDate. It will set postedDate to now every time you modify a Entry including one when you set posted to True.
I implemented it this way: https://djangosnippets.org/snippets/10514/
this implementation uses the data of model instance for all read-only fields and not the data obtained while processing the form
below the same code but using his example
from __future__ import unicode_literals
from django.utils import six
from django.utils.encoding import force_str
__all__ = (
'ReadOnlyFieldsMixin',
'new_readonly_form_class'
)
class ReadOnlyFieldsMixin(object):
"""Usage:
class MyFormAllFieldsReadOnly(ReadOnlyFieldsMixin, forms.Form):
...
class MyFormSelectedFieldsReadOnly(ReadOnlyFieldsMixin, forms.Form):
readonly_fields = ('field1', 'field2')
...
"""
readonly_fields = ()
def __init__(self, *args, **kwargs):
super(ReadOnlyFieldsMixin, self).__init__(*args, **kwargs)
self.define_readonly_fields(self.fields)
def clean(self):
cleaned_data = super(ReadOnlyFieldsMixin, self).clean()
for field_name, field in six.iteritems(self.fields):
if self._must_be_readonly(field_name):
cleaned_data[field_name] = getattr(self.instance, field_name)
return cleaned_data
def define_readonly_fields(self, field_list):
fields = [field for field_name, field in six.iteritems(field_list)
if self._must_be_readonly(field_name)]
map(lambda field: self._set_readonly(field), fields)
def _all_fields(self):
return not bool(self.readonly_fields)
def _set_readonly(self, field):
field.widget.attrs['disabled'] = 'true'
field.required = False
def _must_be_readonly(self, field_name):
return field_name in self.readonly_fields or self._all_fields()
def new_readonly_form_class(form_class, readonly_fields=()):
name = force_str("ReadOnly{}".format(form_class.__name__))
class_fields = {'readonly_fields': readonly_fields}
return type(name, (ReadOnlyFieldsMixin, form_class), class_fields)
Usage:
class BlogEntry(models.Model):
title = models.CharField(unique=True,max_length=50)
description = models.TextField(blank=True)
date = models.DateField(default=datetime.date.today)
postedTime = models.TimeField(null=True)
# all fields are readonly
class BlogEntryReadOnlyForm(ReadOnlyFieldsMixin, forms.ModelForm):
class Meta:
model = BlogEntry
# selected fields are readonly
class BlogEntryReadOnlyForm2(ReadOnlyFieldsMixin, forms.ModelForm):
readonly_fields = ('date', 'postedTime')
class Meta:
model = BlogEntry
or use the function
class BlogEntryForm(forms.ModelForm):
class Meta:
model = BlogEntry
BlogEntryFormReadOnlyForm = new_readonly_form_class(BlogEntryForm, readonly_fields=('description', ))
This will prevent any user from hacking the request:
self.fields['is_admin'].disabled = True
Custom form example:
class MemberShipInlineForm(forms.ModelForm):
is_admin = forms.BooleanField(required=False)
def __init__(self, *args, **kwargs):
super(MemberShipInlineForm, self).__init__(*args, **kwargs)
if 'instance' in kwargs and kwargs['instance'].is_group_creator:
self.fields['is_admin'].disabled = True
class Meta:
model = MemberShip
fields = '__all__'
From the documentation,
class BlogEntryEditForm(ModelForm):
class Meta:
model = BlogEntry
readonly_fields = ['date','postedTime']
I am trying to use the ModelForm to add my data. It is working well, except that the ForeignKey dropdown list is showing all values and I only want it to display the values that a pertinent for the logged in user.
Here is my model for ExcludedDate, the record I want to add:
class ExcludedDate(models.Model):
date = models.DateTimeField()
reason = models.CharField(max_length=50)
user = models.ForeignKey(User)
category = models.ForeignKey(Category)
recurring = models.ForeignKey(RecurringExclusion)
def __unicode__(self):
return self.reason
Here is the model for the category, which is the table containing the relationship that I'd like to limit by user:
class Category(models.Model):
name = models.CharField(max_length=50)
user = models.ForeignKey(User, unique=False)
def __unicode__(self):
return self.name
And finally, the form code:
class ExcludedDateForm(ModelForm):
class Meta:
model = models.ExcludedDate
exclude = ('user', 'recurring',)
How do I get the form to display only the subset of categories where category.user equals the logged in user?
You can customize your form in init
class ExcludedDateForm(ModelForm):
class Meta:
model = models.ExcludedDate
exclude = ('user', 'recurring',)
def __init__(self, user=None, **kwargs):
super(ExcludedDateForm, self).__init__(**kwargs)
if user:
self.fields['category'].queryset = models.Category.objects.filter(user=user)
And in views, when constructing your form, besides the standard form params, you'll specify also the current user:
form = ExcludedDateForm(user=request.user)
Here example:
models.py
class someData(models.Model):
name = models.CharField(max_length=100,verbose_name="some value")
class testKey(models.Model):
name = models.CharField(max_length=100,verbose_name="some value")
tst = models.ForeignKey(someData)
class testForm(forms.ModelForm):
class Meta:
model = testKey
views.py
...
....
....
mform = testForm()
mform.fields["tst"] = models.forms.ModelMultipleChoiceField(queryset=someData.objects.filter(name__icontains="1"))
...
...
Or u can try something like this:
class testForm(forms.ModelForm):
class Meta:
model = testKey
def __init__(self,*args,**kwargs):
super (testForm,self ).__init__(*args,**kwargs)
self.fields['tst'].queryset = someData.objects.filter(name__icontains="1")
I know this is old; but its one of the first Google search results so I thought I would add how I found to do it.
class CustomModelFilter(forms.ModelChoiceField):
def label_from_instance(self, obj):
return "%s %s" % (obj.column1, obj.column2)
class CustomForm(ModelForm):
model_to_filter = CustomModelFilter(queryset=CustomModel.objects.filter(active=1))
class Meta:
model = CustomModel
fields = ['model_to_filter', 'field1', 'field2']
Where 'model_to_filter' is a ForiegnKey of the "CustomModel" model
Why I like this method:
in the "CustomModelFilter" you can also change the default way that the Model object is displayed in the ChoiceField that is created, as I've done above.
is the best answer:
BookDemoForm.base_fields['location'] = forms.ModelChoiceField(widget=forms.Select(attrs={'class': 'form-control select2'}),queryset=Location.objects.filter(location_for__fuel=True))