在django上編輯實際對象之前保存相關對象admin

Question

在django管理員表單上編輯實際對象之前是否可以保存相關對象？

例如：

在models.py

class Parent(model.Model): 
    pass 

class Child(model.Model): 
    parent = models.ForeignKey(Parent) 

@receiver(post_save,sender = Parent) 
def notify_parent_save(sender, instance=None, **kwargs): 
    print "Parent save" 

@receiver(post_save,sender = Child) 
def notify_child_save(sender, instance=None, **kwargs): 
    print "Child saved" 

在admin.py

class ChildInline(admin.TabularInline): 
    model = Child 
    extra = 1 

class ParentsAdmin(admin.ModelAdmin): 
    inlines = [ChildInline] 

admin.site.register(Parent,ParentsAdmin) 

現在，Django管理，如果我救一個父對象，它會在控制檯上輸出。

Parent save 
Child save 

我需要這在revese順序發生：根據你究竟想在你的信號做

Child save 
Parent save 

Answer 1

下面將先救孩子：

class ParentAdmin(admin.ModelAdmin): 
    inlines = [ChildInline] 

    def save_model(self, request, obj, form, change): 
     pass # don't actually save the parent instance 

    def save_formset(self, request, form, formset, change): 
     formset.save() # this will save the children 
     form.instance.save() # form.instance is the parent 

Answer 2

，可你只需要改變的post_save到pre_save爲兒童模式？

Answer 3

ccrisan的回答使我在正確的軌道上，但我認爲這是關於保存那些尚未存在於數據庫實例的行爲缺陷。在這種情況下，不可能首先保存相關的對象，因爲沒有可以指向的外鍵。對我來說，下面的擴展做的伎倆：

class ParentAdmin(admin.ModelAdmin): 
    inlines = [ChildInline] 

    def save_model(self, request, obj, form, change): 
     if not obj.pk: # call super method if object has no primary key 
      super(ParentAdmin, self).save_model(request, obj, form, change) 
     else: 
      pass # don't actually save the parent instance 

    def save_formset(self, request, form, formset, change): 
     formset.save() # this will save the children 
     form.instance.save() # form.instance is the parent 

Answer 4

我是有在這個職位的答案的問題，所以我想出了一個更簡潔的答案。我遇到了一個問題，因爲使用django-fsm，這裏的其他答案會嘗試多次保存模型（每個表單集一次），而不是最後一次。

def save_model(self, request, obj, form, change): 
    if not obj.pk: # call super method if object has no primary key 
     super(YourAdmin, self).save_model(request, obj, form, change) 
    else: 
     pass # don't actually save the parent instance 

def save_related(self, request, form, formsets, change): 
    form.save_m2m() 
    for formset in formsets: 
     self.save_formset(request, form, formset, change=change) 
    super(YourAdmin, self).save_model(request, form.instance, form, change) 

這一基本只是翻轉save_model的順序和save_related如稱爲Django ModelAdmin source