I use the django admin for updating various data on the MySQL database. I use the basic django admin for this. When entering in new data, I would like to be able to have it so people can only select from a few options to enter in new text data.
For example:
The table holds colors, so instead of letting the admin person (data entry individual in our case) just enter in anything into the text box, how can I get the django admin to only give them several options to choose from?
This can be done via the model field argument choices
myfield = models.CharField(max_length=256, choices=[('green', 'green'), ('red', 'red')])
The only problem with this is that if you already have a value in the database that doesn't match one of these, django might just default it to one of the choices.
If that's a problem and you want to preserve those values, I might override the admin form and either only supply the ChoiceField on add operations or dynamically add whatever is in the DB as one of the valid choices.
class MyForm(ModelForm):
MY_CHOICES = [('green', 'green'), ('red', 'red')]
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwargs)
if self.instance.id:
CHOICES_INCLUDING_DB_VALUE = [(self.instance.field,)*2] + self.MY_CHOICES
self.fields['my_field'] = forms.ChoiceField(
choices=CHOICES_INCLUDING_DB_VALUE)
class MyAdmin(admin.ModelAdmin):
form = MyForm
It's better to define a "models.CharField" field type in your model
your_choices = (
('1', u'yello'),
('2', u'red'),
('3', u'black'),
)
types = models.CharField(max_length=32, choices=your_choices, null=True, blank=True)
Then in "admin.py" you should add this new field in your custom admin class like below.
class YourModelAdmin(admin.ModelAdmin):
fields = ('types', )
admin.site.register(YourModel, YourModelAdmin)
Related
I'm trying to set up a form that allows a tattoo shop to book consultations. There are 2 select fields: select an artist and select a tattoo style. Instead of the default first option of the select field being '--------', I would like them to say 'Preferred Artist' and 'Tattoo Style', respectively.
models.py:
class ConsultationRequest(models.Model):
tattoo_styles = [
('water-color', 'Water Color'),
('blackwork', 'Blackwork'),
]
preferred_artist = models.ForeignKey(Artist, on_delete=models.CASCADE)
tattoo_style = models.CharField(max_length=50, choices = tattoo_styles )
forms.py:
class ArtInformationForm(ModelForm):
class Meta:
model = ConsultationRequest
fields = ['preferred_artist', 'tattoo_style']
def __init__(self, *args, **kwargs):
super(ArtInformationForm, self).__init__(*args, **kwargs)
self.fields['preferred_artist'].empty_label = 'Preferred Artist' # this works
self.fields['tattoo_style'].empty_label = 'Tattoo Style' # this doesn't work
When I display this form in a template, the first option for selecting an artist is 'Preferred Artist', but the first option for selecting a tattoo style is still the default dashes. Not sure why this is. I am thinking it has something to do with them being two different kinds of fields, one being a ForeignKey and one being a CharField. Thanks for any help with this.
I want to provide multiple field names in Django's modelChoiceField's to_field_name
something like
field1 = forms.ModelChoiceField(queryset=myModel.objects.all(), required=False,
empty_label="--------",
to_field_name=["col1, col2"],
widget=forms.Select(attrs={'class':'form-control'}),
)
I have a model like
class Codes(models.Model):
item_code = models.CharField(max_length=50)
item_name = models.CharField(max_length=50)
def __str__(self):
return self.item_code + self.item_name
Now I can set queryset as
field1 = forms.ModelChoiceField(queryset=Codes.objects.all(), required=False,
empty_label="--------",
widget=forms.Select(attrs={'class':'form-control'}),
)
And I will get the combination of two fields in my select tag options
everything works but when I open the edit page, the select box doesn't show the default selected value
Also, I want a combination of fields because when item_code repeats in the database, to_field_name gives an error.
I believe you are interpreting to_field_name wrong:
According to the Django website (Django to_field_name explained):
This optional argument is used to specify the field to use as the value of the choices in the field’s widget. Be sure it’s a unique field for the model, otherwise the selected value could match more than one object. By default it is set to None, in which case the primary key of each object will be used...
Which means you can use the to_field_name to address the form object in HTML.
But it does not say anything about multiple to_field_name values.
Normally the primary key is used to address the object. If you set the to_field_name then that field will be used.
To actually add data into the modelChoiceField object, you would need to do something like this.
class CustomForm(ModelForm):
muscles = forms.ModelMultipleChoiceField(
queryset=None,
to_field_name='name',
required=False,)
def __init__(self, *args, **kwargs):
super(CustomForm, self).__init__(*args, **kwargs)
self.fields['name'].queryset = Users.objects.all()
I have a Django model with a ManyToManyField.
1) When adding a new instance of this model via admin view, I would like to not see the M2M field at all.
2) When editing an existing instance I would like to be able to select multiple options for the M2M field, but display only a subset of the M2M options, depending on another field in the model. Because of the dependence on another field's actual value, I can't just use formfield_for_manytomany
I can do both of the things using a custom ModelForm, but I can't reliably tell whether that form is being used to edit an existing model instance, or if it's being used to create a new instance. Even MyModel.objects.filter(pk=self.instance.pk).exists() in the custom ModelForm doesn't cut it. How can I accomplish this, or just tell whether the form is being displayed in an "add" or an "edit" context?
EDIT: my relevant code is as follows:
models.py
class LimitedClassForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(LimitedClassForm, self).__init__(*args, **kwargs)
if not self.instance._adding:
# Edit form
clas = self.instance
sheets_in_course = Sheet.objects.filter(course__pk=clas.course.pk)
self.Meta.exclude = ['course']
widget = self.fields['active_sheets'].widget
sheet_choices = []
for sheet in sheets_in_course:
sheet_choices.append((sheet.id, sheet.name))
widget.choices = sheet_choices
else:
# Add form
self.Meta.exclude = ['active_sheets']
class Meta:
exclude = []
admin.py
class ClassAdmin(admin.ModelAdmin):
formfield_overrides = {models.ManyToManyField: {
'widget': CheckboxSelectMultiple}, }
form = LimitedClassForm
admin.site.register(Class, ClassAdmin)
models.py
class Course(models.Model):
name = models.CharField(max_length=255)
class Sheet(models.Model):
name = models.CharField(max_length=255)
course = models.ForeignKey(Course)
file = models.FileField(upload_to=getSheetLocation)
class Class(models.model):
name = models.CharField(max_length=255)
course = models.ForeignKey(Course)
active_sheets = models.ManyToManyField(Sheet)
You can see that both Sheets and Classes have course fields. You shouldn't be able to put a sheet into active_sheets if the sheet's course doesn't match the class's course.
I need to make a form, which have 1 select and 1 text input. Select must be taken from database.
model looks like this:
class Province(models.Model):
name = models.CharField(max_length=30)
slug = models.SlugField(max_length=30)
def __unicode__(self):
return self.name
It's rows to this are added only by admin, but all users can see it in forms.
I want to make a ModelForm from that. I made something like this:
class ProvinceForm(ModelForm):
class Meta:
CHOICES = Province.objects.all()
model = Province
fields = ('name',)
widgets = {
'name': Select(choices=CHOICES),
}
but it doesn't work. The select tag is not displayed in html. What did I wrong?
UPDATE:
This solution works as I wanto it to work:
class ProvinceForm(ModelForm):
def __init__(self, *args, **kwargs):
super(ProvinceForm, self).__init__(*args, **kwargs)
user_provinces = UserProvince.objects.select_related().filter(user__exact=self.instance.id).values_list('province')
self.fields['name'].queryset = Province.objects.exclude(id__in=user_provinces).only('id', 'name')
name = forms.ModelChoiceField(queryset=None, empty_label=None)
class Meta:
model = Province
fields = ('name',)
Read Maersu's answer for the method that just "works".
If you want to customize, know that choices takes a list of tuples, ie (('val','display_val'), (...), ...)
Choices doc:
An iterable (e.g., a list or tuple) of
2-tuples to use as choices for this
field.
from django.forms.widgets import Select
class ProvinceForm(ModelForm):
class Meta:
CHOICES = Province.objects.all()
model = Province
fields = ('name',)
widgets = {
'name': Select(choices=( (x.id, x.name) for x in CHOICES )),
}
ModelForm covers all your needs (Also check the Conversion List)
Model:
class UserProvince(models.Model):
user = models.ForeignKey(User)
province = models.ForeignKey(Province)
Form:
class ProvinceForm(ModelForm):
class Meta:
model = UserProvince
fields = ('province',)
View:
if request.POST:
form = ProvinceForm(request.POST)
if form.is_valid():
obj = form.save(commit=True)
obj.user = request.user
obj.save()
else:
form = ProvinceForm()
If you need to use a query for your choices then you'll need to overwrite the __init__ method of your form.
Your first guess would probably be to save it as a variable before your list of fields but you shouldn't do that since you want your queries to be updated every time the form is accessed. You see, once you run the server the choices are generated and won't change until your next server restart. This means your query will be executed only once and forever hold your peace.
# Don't do this
class MyForm(forms.Form):
# Making the query
MYQUERY = User.objects.values_list('id', 'last_name')
myfield = forms.ChoiceField(choices=(*MYQUERY,))
class Meta:
fields = ('myfield',)
The solution here is to make use of the __init__ method which is called on every form load. This way the result of your query will always be updated.
# Do this instead
class MyForm(forms.Form):
class Meta:
fields = ('myfield',)
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
# Make the query here
MYQUERY = User.objects.values_list('id', 'last_name')
self.fields['myfield'] = forms.ChoiceField(choices=(*MYQUERY,))
Querying your database can be heavy if you have a lot of users so in the future I suggest some caching might be useful.
the two solutions given by maersu and Yuji 'Tomita' Tomita perfectly works, but there are cases when one cannot use ModelForm (django3 link), ie the form needs sources from several models / is a subclass of a ModelForm class and one want to add an extra field with choices from another model, etc.
ChoiceField is to my point of view a more generic way to answer the need.
The example below provides two choice fields from two models and a blank choice for each :
class MixedForm(forms.Form):
speaker = forms.ChoiceField(choices=([['','-'*10]]+[[x.id, x.__str__()] for x in Speakers.objects.all()]))
event = forms.ChoiceField(choices=( [['','-'*10]]+[[x.id, x.__str__()] for x in Events.objects.all()]))
If one does not need a blank field, or one does not need to use a function for the choice label but the model fields or a property it can be a bit more elegant, as eugene suggested :
class MixedForm(forms.Form):
speaker = forms.ChoiceField(choices=((x.id, x.__str__()) for x in Speakers.objects.all()))
event = forms.ChoiceField(choices=(Events.objects.values_list('id', 'name')))
using values_list() and a blank field :
event = forms.ChoiceField(choices=([['','-------------']] + list(Events.objects.values_list('id', 'name'))))
as a subclass of a ModelForm, using the one of the robos85 question :
class MixedForm(ProvinceForm):
speaker = ...
I want to make a form used to filter searches without any field being required. For example given this code:
models.py:
class Message(models.Model):
happened = models.DateTimeField()
filename = models.CharField(max_length=512, blank=True, null=True)
message = models.TextField(blank=True, null=True)
dest = models.CharField(max_length=512, blank=True, null=True)
fromhost = models.ForeignKey(Hosts, related_name='to hosts', blank=True, null=True)
TYPE_CHOICES = ( (u'Info', u'Info'), (u'Error', u'Error'), (u'File', u'File'), (u'BPS', u'BPS'),)
type = models.CharField(max_length=7, choices=TYPE_CHOICES)
job = models.ForeignKey(Jobs)
views.py:
WHEN_CHOICES = ( (u'', ''), (1, u'Today'), (2, u'Two days'), (3, u'Three Days'), (7, u'Week'),(31, u'Month'),)
class MessageSearch(ModelForm): #Class that makes a form from a model that can be customized by placing info above the class Meta
message = forms.CharField(max_length=25, required=False)
job = forms.CharField(max_length=25, required=False)
happened = forms.CharField(max_length=14, widget=forms.Select(choices=WHEN_CHOICES), required=False)
class Meta:
model = Message
That's the code I have now. As you can see it makes a form based on a model. I redefined message in the form because I'm using an icontains filter so I didn't need a giant text box. I redefined the date mostly because I didn't want to have to mess around with dates (I hate working with dates! Who doesnt?) And I changed the jobs field because otherwise I was getting a drop down list of existing jobs and I really wanted to be able to search by common words. So I was able to mark all of those as not required
The problem is it's marking all my other fields as required because in the model they're not allowed to be blank.
Now in the model they can't be blank. If they're blank then the data is bad and I don't want it in the DB. However the form is only a filter form on a page to display the data. I'm never going to save from that form so I don't care if fields are blank or not. So is there an easy way to make all fields as required=false while still using the class Meta: model = Message format in the form? It's really handy that I can make a form directly from a model.
Also this is my first serious attempt at a django app so if something is absurdly wrong please be kind :)
You can create a custom ModelForm that suit your needs. This custom ModelForm will override the save method and set all fields to be non-required:
from django.forms import ModelForm
class SearchForm(ModelForm):
def __init__(self, *args, **kwargs):
super(SearchForm, self).__init__(*args, **kwargs)
for key, field in self.fields.iteritems():
self.fields[key].required = False
So you could declare your forms by simply calling instead of the ModelForm, e.g.:
class MessageForm(SearchForm):
class Meta:
model = Message
You could also pass empty_permitted=True when you instantiate the form, e.g.,
form = MessageSearch(empty_permitted=True)
that way you can still have normal validation rules for when someone does enter data into the form.
I would give a try to the django-filter module :
http://django-filter.readthedocs.io/en/develop/
fields are not required. these are filters actually. It would look like this :
import django_filters
class MessageSearch(django_filters.FilterSet):
class Meta:
model = Message
fields = ['happened', 'filename', 'message', '...', ]
# django-filter has its own default widgets corresponding to the field
# type of the model, but you can tweak and subclass in a django way :
happened = django_filters.DateFromToRangeFilter()
mandatory, hidden filters can be defined if you want to narrow a list of model depending on something like user rights etc.
also : setup a filter on a 'reverse' relationship (the foreignkey is not in the filtered model : the model is referenced elsewhere in another table), is easy, just name the table where the foreign key of the filtered model field is :
# the 'tags' model has a fk like message = models.ForeignKey(Message...)
tags= django_filters.<some filter>(name='tags')
quick extendable and clean to setup.
please note I didn't wrote this module, I'm just very happy with it :)