class Colour(models):
...
def colour_preview(self):
return format_html(...)
class ColourTheme(models):
colour1 = models.ForeignKey(Colour)
colour2 = models.ForeignKey(Colour)
colour3 = models.ForeignKey(Colour)
...
def preview(self):
for field in self._meta.get_fields(include_parents=False):
if (field.related_model == Colour):
field.colour_preview()
I have a ColourTheme model with multiple Colour foreign keys, and I want to call a function on each of the Colour objects referred to by those fields. The last line of code above fails. I would like to call colour_preview on all Colour fields without hardcoding them (self.colour1.colour_preview() works but not ideal).
How might I achieve this?
You cannot refer to the field in order to access related object method.
Try something like this (I haven't tested it):
class ColourTheme(models):
colour1 = models.ForeignKey(Colour)
colour2 = models.ForeignKey(Colour)
colour3 = models.ForeignKey(Colour)
...
def preview(self):
for field in self._meta.get_fields(include_parents=False):
if (field.related_model == Colour):
field_obj = field.value_from_obj(self) # To get obj reference
field_obj.colour_preview()
Related
In Odoo 10, I want to change the value of a variable when the forecasted quantity of a product is changed. I tried using the #api.onchange decorator, but it doesn't work. The forecasted quantity change, but the variable keeps the same value. I have this:
class MyProduct(models.Model):
_inherit = 'product.product'
was_changed = fields.Boolean(default = False)
#api.onchange('virtual_available')
def qtychanged(self):
self.was_changed = True
_logger.info('Product_Qty_Cahnged: %s',str(self.virtual_available))
In this code, if the forecasted quantity of a product would change, the variable was_changed should be set to True, but nothing happens.
After that, I tried to overwrite the write method for my custom class, like this:
class MyProduct(models.Model):
_inherit = 'product.product'
was_changed = fields.Boolean(default=False)
#api.multi
def write(self, values):
if values['virtual_available']:
values['was_changed'] = True
# THE FOLLOWING LINES WERE IN THE ORIGINAL WRITE METHOD
res = super(MyProduct, self).write(values)
if 'standard_price' in values:
self._set_standard_price(values['standard_price'])
return res
But still, I have the same result. I can't seem to get that flag to change. So, any ideas?
Try this:
class MyProduct(models.Model):
_inherit = 'product.product'
was_changed = fields.Boolean(default = False)
#api.onchange('virtual_available')
def qtychanged(self):
self.write({'was_changed': True})
_logger.info('Product_Qty_Cahnged: %s',str(self.virtual_available))
I want to get the parent class values with each child values? How can I identify child objects to fetch?
I have the Django model structure like this.
class Category(models.Model):
name = models.CharField(max_length=80)
class Place(models.Model):
name = models.CharField(max_length=50)
address = models.CharField(max_length=80)
category = models.ForeignKey('Category')
class PizzaRestaurant(Place):
serves_hot_dogs = models.BooleanField(default=False)
serves_pizza = models.BooleanField(default=False)
class PastaRestaurant(Place):
extra = models.CharField(max_length=80)
When we do operation we may save the object like below. And it saved into the db as i expected. two entry in the Place table and each entry in each child object table.
a = Category()
a.name = "pasta"
b = Category()
b.name = "pizza"
a.save()
b.save()
x = PastaRestaurant()
x.address = "Pasta Address"
x.name = "Pastamonia"
x.extra = "some extra"
x.category = a
y = PizzaRestaurant()
y.address = "Pizza Address"
y.name = "Dominos"
y.serves_hot_dogs = 1
y.serves_pizza = 0
y.category = b
x.save()
y.save()
Now I need to access the like this
p = Place.objects.get(id=1)
How can I know, which objects/attributes belongs to the place objects?
So when I fetch the place with common attributes and should be able get the corresponding child objects values also.
Or any other model design work for my need?
If you want to access the child model's attributes you need to fetch it as that model, i e PizzaRestaurant or PastaRestaurant, otherwise you will only get a Place object.
If you need to get all Places regardless of subclass take a look at InheritanceManager from django-model-utils. Using this you can implement overloaded operations to perform subclass-specific actions.
django-polymorphic does this beautifully, improving the abilities to work with model inheritance like so:
from polymorphic.models import PolymorphicModel
class Place(PolymorphicModel):
...
class PizzaRestaurant(Place):
...
class PastaRestaurant(Place:
...
>>> some_place = Place.objects.create(name="Walmart")
>>> some_pizza_place = PizzaRestaurant.objects.create(name="Slice King", address="101 Main St., Bismarck, ND", category = Category.objects.first(),serves_pizza=True)
>>> some_pizza_place.instance_of(PizzaPlace)
True
>>> PizzaRestaurant.objects.all()
queryset<['Slice King',]>
>>> Place.objects.all()
queryset<['Walmart', 'Slice King',]>
I am not sure exactly how achieve this.
I have a model defined as
class Post(ndb.Model):
author_key = ndb.KeyProperty(kind=Author)
content = ndb.StringProperty(indexed=False)
created = ndb.DateTimeProperty(auto_now_add=True)
title = ndb.StringProperty(indexed=True)
topics = ndb.StructuredProperty(Concept, repeated=True)
concise_topics = ndb.ComputedProperty(get_important_topics())
#classmethod
def get_important_topics(cls):
cls.concise_topics = filter(lambda x: x.occurrence > 2, cls.topics)
return cls.concise_topics
I like to set the value of concise_topics (Which is on the same type as topics) to a subset acheived via get_important_topics method. This should happen the moment the topics property has been set.
How do I define the "concise_topics" property in the Post class ?
With class method, you don't have access to the instance values. And also you shouldn't call the function, only pass it to the computed property, and let it call by itself.
class Post(ndb.Model):
author_key = ndb.KeyProperty(kind=Author)
content = ndb.StringProperty(indexed=False)
created = ndb.DateTimeProperty(auto_now_add=True)
title = ndb.StringProperty(indexed=True)
topics = ndb.StructuredProperty(Concept, repeated=True)
def get_important_topics(self):
return filter(lambda x: x.occurrence > 2, self.topics)
concise_topics = ndb.ComputedProperty(get_important_topics)
As far as I remember the computed property is set on each put call, so your topics should be already there by that time.
I have a model and a method on it as follows:
class Results(models.Model):
t_id = models.TextField(blank=True)
s_result_id = models.TextField(blank=True,primary_key=True)
s_name = models.TextField(blank=True)
s_score = models.FloatField(blank=True, null=True)
... (some other fields with huge data)
def get_s_score(self):
return 100 * self.s_score
On a view, I am trying to call get_s_score method from inside values. I have to use values to avoid selecting other fields with huge data.
def all_recentsiteresults(request,t_id1):
Result = Results.objects.filter(t_id=t_id1).values('s_result_uid','s_name',get_s_score())
You can't use the model's method in the values() method. But you can use the only() method to decrease the memory usage:
Results.objects.only('s_result_id', 's_name', 's_score').filter(t_id=t_id1)
I have two models:
class ModManager(models.Manager):
def myfilter(self, options = dict()):
if options.has_key('not_image'):
kwargs['image__isnull'] = False
return self.filter(**kwargs)
class Model_1(models.Model):
...
objects = MyManager()
class Model_2(models.Model):
something = models.ForeignKey(Model_1)
something_else = ...
...
How to get all data from Model_2 related to Model_1 in MyManager? I want to get one query. I have so far:
in Model_1:
def get_model_2(self):
self.model_2_objs = self.model_2_set.all()
But it generates many queries when I calling get_model_2 function.