Django的窗体缓存填充形式

Question

我正在填充在Django形式的选择，

的问题是，当我在浏览器中看到的那样，今年的榜单是根据数据库的罚款，但是当我改变数据库中的某个日期，年份选择列表不会更新。

class PlanForm(forms.Form): 

    def get_prices(): 
     return forms.ChoiceField(choices=map(lambda x: (x.pk, unicode(x.length) + _(' Day Listing/') + unicode(x.pics) + _(' Photos: ') + _('$ ') + unicode(x.price) ), Pricing.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Plans'), widget=forms.RadioSelect) 

    def get_options(): 
     return forms.MultipleChoiceField(choices=map(lambda x: (x.pk, unicode(x) + _(' : $') + unicode(x.price)), PricingOptions.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Ads Options'), widget=forms.CheckboxSelectMultiple, required=False) 

    def __init__(self, *args, **kwargs): 
     print 'passou no init' 
     super(PlanForm, self).__init__(*args, **kwargs) 
     self.fields['pricing'] = self.get_prices() 
     self.fields['pricing_options'] = self.get_options() 


    pricing = get_prices() 
    pricing_options = get_options() 

我试试这个代码，但我得到的错误

get_prices（）不带任何参数（1给出）

我怎么能SOVE呢？

Answer 1

类方法（例如get_prices）至少需要一个参数self，该参数将被调用该方法的类实例填充。

Answer 2

将@staticmethod修饰符添加到您的方法中。默认情况下，Python假定函数在类中作为方法被defiened，并将“self”作为第一个参数传递。 staticmethod可防止此默认行为。

class PlanForm(forms.Form): 

    @staticmethod 
    def get_prices(): 
     return forms.ChoiceField(choices=map(lambda x: (x.pk, unicode(x.length) + _(' Day Listing/') + unicode(x.pics) + _(' Photos: ') + _('$ ') + unicode(x.price) ), Pricing.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Plans'), widget=forms.RadioSelect) 

    @staticmethod 
    def get_options(): 
     return forms.MultipleChoiceField(choices=map(lambda x: (x.pk, unicode(x) + _(' : $') + unicode(x.price)), PricingOptions.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Ads Options'), widget=forms.CheckboxSelectMultiple, required=False) 

    def __init__(self, *args, **kwargs): 
     print 'passou no init' 
     super(PlanForm, self).__init__(*args, **kwargs) 
     self.fields['pricing'] = self.get_prices() 
     self.fields['pricing_options'] = self.get_options() 


    pricing = get_prices() 
    pricing_options = get_options() 

Answer 3

试试：

class PlanForm(forms.Form): 

    def __init__(self, *args, **kwargs): 
     print 'passou no init' 
     super(PlanForm, self).__init__(*args, **kwargs) 
     self.fields['pricing'] = forms.ChoiceField(choices=map(lambda x: (x.pk, unicode(x.length) + _(' Day Listing/') + unicode(x.pics) + _(' Photos: ') + _('$ ') + unicode(x.price) ), Pricing.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Plans'), widget=forms.RadioSelect) 
     self.fields['pricing_options'] = forms.MultipleChoiceField(choices=map(lambda x: (x.pk, unicode(x) + _(' : $') + unicode(x.price)), PricingOptions.objects.filter(enable=True,site=settings.SITE_ID)),label=_('Ads Options'), widget=forms.CheckboxSelectMultiple, required=False)