Question

我正在使用django-ajax-selects，这是一个免费提供的django应用程序，可提供jquery自动完成功能。

我已经完成了它 - 即它自动填充我想要的表单字段。但是我有一个问题......我在ModelForm中使用它，它将Partnership对象添加到数据库中：

class Skater(models.Model):
    name = models.CharField(max_length=64)
    surname = models.CharField(max_length=64)
    gender = models.CharField(max_length=1, choices=GENDER_CHOICES)

class Partnership(models.Model):
    female_partner = models.ForeignKey(Skater, limit_choices_to = {'gender': FEMALE}, related_name='female_partner_set')
    male_partner = models.ForeignKey(Skater, limit_choices_to = {'gender': MALE}, related_name='male_partner_set')

我希望用户能够在female_partner和male_partner字段中输入名称和姓氏，即使这样的Skater对象不存在，我也希望创建该对象。我该怎么做呢？我不能将代码放在表单的save方法中，因为该字段不会验证（它不是有效的Skater）。

编辑1： 添加更多代码...

表格：

class PartnershipAddForm(forms.ModelForm):
    female_partner = AutoCompleteSelectField('female_skater',required=True)
    male_partner = AutoCompleteSelectField('male_skater',required=True)

    class Meta:
        model = Partnership

settings.py：

AJAX_LOOKUP_CHANNELS = {
    'female_skater' : ('skaters.lookups', 'FemaleLookup'),
    'male_skater' : ('skaters.lookups', 'MaleLookup'),
}

lookups.py（MaleLookup除了gender = MALE之外是相同的）：

class FemaleLookup(object):

    def get_query(self,q,request):
        """ return a query set.  you also have access to request.user if needed """
        return Skater.objects.filter(Q(gender=FEMALE) & (Q(name__istartswith=q) | Q(surname__istartswith=q)))

    def format_item(self,skater):
        """ simple display of an object when it is displayed in the list of selected objects """
        return unicode(skater)

    def format_result(self,skater):
        """ a more verbose display, used in the search results display.  may contain html and multi-lines """
        return "%s<br/>" % unicode(skater)

    def get_objects(self,ids):
        """ given a list of ids, return the objects ordered as you would like them on the admin page.
            this is for displaying the currently selected items (in the case of a ManyToMany field)
        """
        return Skater.objects.filter(pk__in=ids).order_by('name','surname')

Answer 1

AutoCompleteSelectField保存对象的id而不是文本，这就是我一直有“必需”错误的原因（以及为什么Daniel的解决方案不起作用）。值变量为空，因为不存在的Skater没有id。

我不确定这是最好的方法，但我最终使用的是AutoCompleteField而不是AutoCompleteSelectField。 AutoCompleteField保存文本，但它不会为我创建Skater对象。

代码：

class PartnershipAddForm(forms.ModelForm):
    female_partner = AutoCompleteField('female_skater',required=True)
    male_partner = AutoCompleteField('male_skater',required=True)

    class Meta:
        model = Partnership

    def save(self):
        partners = [self.cleaned_data['female_partner'],
                    self.cleaned_data['male_partner']]
        name = ['','']
        surname = ['','']
        for i in [0,1]:
            name[i],surname[i] = get_name_surname(partners[i])
        partners = [None,None]
        partners_created = [None,None]
        gender = [FEMALE,MALE]
        for i in [0,1]:        
            partners[i],partners_created[i] = Skater.objects.get_or_create(
                                            name=name[i],
                                            surname=surname[i],
                                            gender=gender[i]
                                        )

         partnership, created = Partnership.objects.get_or_create(
                                    female_partner=partners[0],
                                    male_partner=partners[1],
                                )
         return partnership

Answer 2

看起来您需要从ajax选择子类化AutoCompleteSelectField并覆盖其clean方法。

def clean(self, value):
    if value:
        lookup = get_lookup(self.channel)
        objs = lookup.get_objects( [value] )
        if objs:
            return objs[0]
        else:
            firstname, surname = value.split(" ")
            gender = self.channel.split("_")[0]
            new_skater = Skater(name=firstname, surname=surname, gender=gender)
            return new_skater
    else:
        if self.required:
            raise forms.ValidationError(self.error_messages['required'])
        return None

Answer 3

我们能看到你的表格是什么样的吗？我认为您需要覆盖ModelForm中的save（）方法，因此首先保存female_partner和male_partner，然后保存表单实例（又名Parntership实例）。

django-ajax-choices app：当数据库中还没有新对象时，如何创建新对象？

3 个答案: