问题
你好。我试图找出使用一种形式创建一个父对象然后创建 0-n 个子对象的最佳方法。我假设 ModelForms 是我需要做的,但我很难理解如何构建模板和视图。有人愿意解释如何创建 n 个子对象吗?
这项研究
我已经阅读了与此相关的其他几篇文章和帖子:
- django model/modelForm - 如何在choiceField中获得动态选择?
- https://stackoverflow.com/questions/5575560/how-do-i-create-a-drop-down-menu-in-django-using-a-modelform-with-dynamic-values
- http://collingrady.wordpress.com/2008/02/18/editing-multiple-objects-in-django-with-newforms/
- 覆盖 Django ModelForm 中的保存方法
仅举几例。
细节
我有两个这样的模型:
// 模型.py
class DataItem(models.Model):
name = models.CharField(max_length=255)
date_created = models.DateTimeField(auto_now_add=True)
date_last_updated = models.DateTimeField(auto_now_add=True)
owner = models.ForeignKey(User, blank=False)
def __unicode__(self):
return self.name
class DataItemSet(models.Model):
item = models.ForeignKey(DataItem, blank=False)
type_ind = models.IntegerField()
我创建了两个 ModelForms 来对应:
// 表单.py
class CreateDataItemForm(forms.ModelForm):
class Meta:
model = DataItem
exclude = ('owner',)
def save(self, user, commit=True):
item = super(CreateDataItemForm,self).save(commit=False)
item.owner = user
if commit:
item.save()
return item
class CreateDataItemSetForm(forms.ModelForm):
class Meta:
model = DataItemSet
exclude = ('item',)
def save(self, parent, commit=True):
set = super(CreateDataItemSetForm,self).save(commit=False)
set.item = parent
if commit:
set.save()
return set
DataItem
在我看来,我正在尝试让一个表单提交DataItemSet
由DataItem
. 以下是表单输出的示例:
和模板:
<form action="." method="post">
{% csrf_token %}
<table>
{{ create_form.as_table }}
</table>
<table>
<tr>
<th>What to track:</th>
<td>
<select>
<option value="1">Number</option>
<option value="2">Currency ($)</option>
<option value="3">Date</option>
<option value="4">Day</option>
<option value="5">Time</option>
</select>
</td>
<td>
</td>
</tr>
<tr>
<th>What to track:</th>
<td>
<select>
<option value="1">Number</option>
<option value="2">Currency ($)</option>
<option value="3">Date</option>
<option value="4">Day</option>
<option value="5">Time</option>
</select>
</td>
<td>
<button type="button">+</button>
</td>
</tr>
</table>
<p>
<button type="submit">Create</button>
</p>
</form>
最后,观点:
// 视图.py
@login_required
@csrf_protect
def create_data_item(request):
create_form = CreateDataItemForm()
c = {'create_form':create_form}
c.update(csrf(request))
if request.method == 'POST':
data = request.POST.copy()
form = CreateDataItemForm(data, instance=DataItem())
item_sets = [CreateDataItemSetForm(request.POST, prefix=str(x), instance=DataItemSet()) for x in range(0,9)]
if form.is_valid():
# create new data item
new_item = form.save(request.user)
#create new set of stuff to track
for item_set in item_sets:
new_item_set = item_set.save(new_item)
# return to the add entry page
return redirect('/add')
else:
return render_to_response('internal/create_data_item.html',c)
我错过了如何允许从form
. 我无法用 ModelForm 弄清楚。
谢谢你的帮助!