So I have a parent class BaseAdd that I'm trying to subclass. The BaseAdd uses self.left and self.right, I want to use self.nodes to make it easier to access both left and right at once:
class BaseAdd():
def __init__(self, leftright):
self.left = leftright[0]
self.right = leftright[1]
class Add(BaseAdd):
def __init__(self, leftright):
self.nodes = leftright
#property
def left(self):
return self.nodes[0]
#left.setter
def left(self, value):
self.nodes[0] = value
foo = Add(('L', 'R'))
foo.left = "new"
print(foo.left, foo.nodes[0])
>>> ('new', 'L')
The problem is that the setter is never getting called, my hunch is that it's using the BaseAdd.left somehow instead. How can I make the setter properly set the list element?
Related
I have a model:
class PastStudy(Model):
grade_average = FloatField(null=True)
I have a modelform as below:
class PastStudyForm(ModelForm):
class Meta:
model = PastStudy
fields = ('grade_average', )
What I have in view:
...
if request.POST:
past_study_form = PastStudyForm(request.POST)
if past_study_form.is_valid():
return HttpResponse(past_study_form.cleaned_data['grade_average'])
else:
profile_filter_past_study_form = ProfileFilterPastStudyForm()
...
What I need is that I want to write a clean method for PastStudyForm so that in case I entered 90 as grade average, HttpResponse converts it two 0-20 grading scheme and returns 18.
I tried this and I was still getting 90 not 18
class PastStudyForm(ModelForm):
class Meta:
model = PastStudy
fields = ('grade_average', )
def clean(self):
cleaned_data = super().clean()
grade_average = self.cleaned_data['grade_average']
self.cleaned_data['grade_average'] = grade_average/5
return cleaned_data
and This:
class PastStudyForm(ModelForm):
class Meta:
model = PastStudy
fields = ('grade_average', )
def clean_grade_average(self):
grade_average = self.cleaned_data['grade_average']
data = grade_average/5
return data
However, I still get 90. I also have tried a few other methods but I still was getting 90 in HttpResponse
Maybe using clean method be wrong and I should do something else!
The real code is huge and I have summarized it in here and other aspects of the problem are not explained in here. That is why I prefer and expect to get a response in which I am advised how to it in the form definition, not other methods such as converting it in the view.
in your clean method, you assign the result of your calculation method into self.cleaned_data,
while you are returning cleaned_data not self.cleaned_data.
it is different variable.
try this instead:
self.cleaned_data = super().clean()
grade_average = self.cleaned_data['grade_average']
self.cleaned_data['grade_average'] = grade_average/5
return self.cleaned_data
I'm making a big mess trying to access the object that I passed from the view to the form.
class PrenotaForm(forms.ModelForm):
ORARI_CHOICES = ()
def __init__(self, *args, **kwargs):
DICT_ORARI_CHOICES = kwargs.pop('ORARI_CHOICES_NEW', {})
ORARI_CHOICES_NEW = []
for key, value in DICT_ORARI_CHOICES.items():
temp = [key,value]
ORARI_CHOICES_NEW.append(temp)
super(PrenotaForm, self).__init__(*args, **kwargs)
self.ORARI_CHOICES = ORARI_CHOICES_NEW
print("EEEEEEEEEEEEEEE" + str(self.ORARI_CHOICES))
print(ORARI_CHOICES)
I don't understand why inside the init the ORARI_CHOICES is populated as shown in console output:
EEEEEEEEEEEEEEE[['è uguale', 'Indifferente'], ['845', '08:45'], ['900', '09:00'], ['915', {'label': '09:15', 'disabled': 'disabled'}], ['930', {'label': '09:30', 'disabled': 'disabled'}], ['945', '09:45'], ['1000', '10:00'], ['1015', '10:15'], ['1030', '10:30'], ['1045', '10:45'], ['1100', '11:00'], ['1115', '11:15'], ['1130', '11:30'], ['1145', '11:45']]
but outside the init the ORARI_CHOICE is still empty:
print(ORARI_CHOICES)
since the print does not output nothing.
How can I override the ORARI_CHOICES = () and make it avalable globally in the class after every GET request performed in the view?
if request.method == 'GET':
size_gruppi = 30
print("gruppi size is : " + str(size_gruppi))
ORARI_CHOICES = (
('è uguale', "Indifferente"),
('845', "08:45"),
('900', "09:00"),
('915', "09:15"),
('930', "09:30"),
('945', "09:45"),
('1000', "10:00"),
('1015', "10:15"),
('1030', "10:30"),
('1045', "10:45"),
('1100', "11:00"),
('1115', "11:15"),
('1130', "11:30"),
('1145', "11:45"),
)
orari_map = map(list,ORARI_CHOICES)
orari_dict = dict(ORARI_CHOICES)
print(orari_dict)
counter = 0
for key in orari_map:
if key[0] != 'è uguale':
tot_in_fascia = sum(filter(None, Iscritto.objects.filter(fasce_orarie=key[0]).aggregate(Sum('size_adulti'), Sum('size_giovani')).values()))
print(tot_in_fascia)
if tot_in_fascia >= size_gruppi:
print("fascia " + key[0] + " è al completo ")
orari_dict.update({key[0]: {'label': key[1], 'disabled': 'disabled'}})
form = PrenotaForm(ORARI_CHOICES_NEW = orari_dict)
return render(request, "prenota.html", {'form': form, 'posti_liberi': posti_disponibili, 'giovani_iscritti': giovani_iscritti})
You should set ORARI_CHOICES as a class/static attribute.
class PrenotaForm(forms.ModelForm):
ORARI_CHOICES = []
def __init__(self, *args, **kwargs):
DICT_ORARI_CHOICES = kwargs.pop('ORARI_CHOICES_NEW', {})
# ORARI_CHOICES_NEW = []
for key, value in DICT_ORARI_CHOICES.items():
temp = [key,value]
self.__class__.ORARI_CHOICES.append(temp)
super(PrenotaForm, self).__init__(*args, **kwargs)
print("EEEEEEEEEEEEEEE" + str(self.ORARI_CHOICES))
Now, PrenotaForm.ORARI_CHOICES is already accessible. PrenotaForm.ORARI_CHOICES will always be accessible, but it returns empty list, untill you do not create instance of PrenotaForm. After instance creation of PrenotaForm, __init__ method will be called and data will be added inside ORARI_CHOICES.
I am trying to update 4 StringVar() with values read only after a file is opened. I'm trying to use an abstract method set_values() on the class TestPage to update the 4 StringVar().
...
class TestPage(Tk.Frame):
def __init__(self, parent, *controller):
Tk.Frame.__init__(self, parent)
self.x = Tk.StringVar()
self.y = Tk.StringVar()
self.z = Tk.StringVar()
self.w = Tk.StringVar()
...
x_label = ttk.Label(self, textvariable=self.x)
y_label = ttk.Label(self, textvariable=self.x)
z_label = ttk.Label(self, textvariable=self.x)
w_label = ttk.Label(self, textvariable=self.x)
...
def set_values(self):
self.x.set(some.list[0])
self.y.set(some.other_list.last_index)
self.z.set(some.list_total_entries)
self.w.set('herro worr')
...
TestPage inherets from Tk.Frame. I believe I 'instantiate' the TestPage object when I call show_frame() in the main Application class, which inherets from Tk:
# ***** Tkinter Gui classes *****
# Main container, called by app.gui.Application() in main.py
class Application(Tk.Tk):
def __init__(self, *args, **kwargs):
Tk.Tk.__init__(self, *args, **kwargs)
container = Tk.Frame(self, name='container')
container.pack(side="top", fill="both", expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0, weight=1)
self.frames = {}
for F in (EntryPage, TestPage):
frame = F(container, self)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame(EntryPage)
# ***** Change view/frame *****
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
# ***** Open file *****
def open_file(self):
functions.load_file()
...
I would like to call set_values() from my existing load_file function which is in a seperate functions module. I call load_file() to do some populating of graphs, and to parse the file selected for openening.
...
def load_file():
...
if file_name:
gui.TestPage.set_values()
...
...
When I try I get the error:
TypeError: unbound method set_values() must be called with TestPage instance as first argument (got nothing instead)
I need to call the method on the instantiated instance of TestPage, but I do not understand what parameter to supply to set_values() to indicate self or the current instance of TestPage. In the Application class I thought I was instantiating TestPage as frame in the line frame = F(container, self). But I have not been able to reference set_values() using frame either.
I am not even sure this is the best way to do it. I tried to replace the method with binds, events, and also #classmethod and #staticmethod, but with no real succes. Should I be using an abstract method for this?
The values you are changing are attributes of an object, so you need to change them via the instance. In other words, don't pass something to the "self" parameter of a class or abstract function, simply call the function on the object itself.
For example:
...
testfile = TestPage(...)
...
load_file(testpage)
...
def load_file(page):
...
page.set_values()
Playing around with inheritance and came across an error stating that I am inputing too many arguments. What could I be doing wrong?
This first file is called media.py
class Video():
def __init__(self, title, duration):
self.title = title
self.duration = duration
class Movie(Video):
def __init__(self, movie_story, movie_poster, trailer_youtube):
Video.__init__(self, title, duration)
self.storyline = movie_story
self.poster_image_url = movie_poster
self.trailer_youtube_url = trailer_youtube
def show_trailer(self):
webbrowser.open(self.trailer_youtube_url)
class TvShow(Video):
def __init__(self, season, episode, tv_station):
Video.__init__(self, title, duration)
self.season = season
self.episode = episode
self.tv_station = tv_station
This second file creates the objects.
import fresh_tomatoes
import media
family_guy = media.TvShow("Family Guy",
"2000-Present",
"Fifteen Seasons",
"Twenty-Eight",
"Fox")
print family_guy.title
The terminal output states I'm passing 6 arguments when only 4 may be accepted. Why is that?
Calling the parent __init__ will only invoke it , but you still need to pass in the arguments to it.
So when you invoke __init__ method for TvShow it only expects 3 +1(self) arguments , while you were trying to send more than that. So to solve the issue you just need to increase the number of arguments excepted by the __init__.
class Video():
def __init__(self, title, duration):
self.title = title
self.duration = duration
class Movie(Video):
def __init__(self, movie_story, movie_poster, trailer_youtube):
Video.__init__(self, title, duration)
self.storyline = movie_story
self.poster_image_url = movie_poster
self.trailer_youtube_url = trailer_youtube
def show_trailer(self):
webbrowser.open(self.trailer_youtube_url)
class TvShow(Video):
def __init__(self, season, episode, tv_station, title, duration):
Video.__init__(self, title, duration)
self.season = season
self.episode = episode
self.tv_station = tv_station
I'm writing a custom EnumMeta class in Python 2.7 that will collect enum keys and values from some class and augment that class with some additional fields.
class EnumMeta(type):
def __init__(cls, name, bases, props):
cls.__all_values__ = [...] # collect all interesting properties
def __contains__(cls, value):
return value in cls.__all_values__
class TheFellowshipOfTheRing(object):
__metaclass__ = EnumMeta
FRODO = 'Frodo Baggins'
SAM = 'Samwise "Sam" Gamgee'
MERRY = 'Meriadoc "Merry" Brandybuck'
PIPPIN = 'Peregrin "Pippin" Took'
GANDALF = 'Gandalf the Grey'
ARAGORN = 'Aragorn (Strider)'
LEGOLAS = 'Legolas'
GIMLI = 'Gimli'
BOROMIR = 'Boromir'
print 'Gandalf the Grey' in TheFellowshipOfTheRing
# True
print 'Saruman' in TheFellowshipOfTheRing
# False
I'm wondering if implementing container-specific functions, such as __contains__, on a metaclass is a dangerous thing to do, and if so, why?