[Fixed]-Django admin different inlines for change and add view

It works with Django 1.5+ and seems fine & elegant:

// admin.py
class BoxAdmin(ModelAdmin):

    inlines = ()

    def change_view(self, request, object_id, form_url='', extra_context=None):
        self.inlines = (ItemChangeInline, )
        return super(BoxAdmin, self).change_view(request, object_id)

    def add_view(self, request, form_url='', extra_context=None):
        self.inlines = (ItemAddInline, )
        return super(BoxAdmin, self).add_view(request)

hope it can be useful for anyone

Here is the code that seems to be working:

class BoxAdmin(admin.ModelAdmin):
   def change_view(self, request, obj_id):
        self.inlines=[ItemChangeInline,]
        for inline_class in self.inlines:
            inline_instance = inline_class(self.model, self.admin_site)
            self.inline_instances.append(inline_instance)
        return super(BoxAdmin, self).change_view(request, obj_id)
    def add_view(self, request):
        self.inlines=[ItemAddInline,]
        for inline_class in self.inlines:
            inline_instance = inline_class(self.model, self.admin_site)
            self.inline_instances.append(inline_instance)
        return super(BoxAdmin, self).add_view(request)

However, this looks inelegant, cause this part:

            for inline_class in self.inlines:
            inline_instance = inline_class(self.model, self.admin_site)
            self.inline_instances.append(inline_instance)

is a copy-paste from init method of admin.ModelAdmin (so it is run twice).

Why in add_view you have .add_view(self, request) and in change view you have .change_view(self.request, ..)? I believe, you don’t need self in add_view, since you use super.

I had a situation where I needed to show an Inline based on the admin site that you were on for a given story.

Expanding on alekwisnia’s answer, I was able to get dynamic inlines working for Django 1.3 using the following code:

In highlights/admin.py

class HighlightInline(generic.GenericTabularInline):
    model = Highlight
    extra = 1
    max_num = 4
    fields = ('order', 'highlight')
    template = 'admin/highlights/inline.html'

class HighlightAdmin(admin.ModelAdmin):
    def regulate_highlight_inlines(self):
        highlights_enabled = Setting.objects.get_or_default('highlights_enabled', default='')
        highlight_inline_instance = HighlightInline(self.model, self.admin_site)
        highlight_found = any(isinstance(x, HighlightInline) for x in self.inline_instances)
        if highlights_enabled.strip().lower() == 'true':
            if not highlight_found:
                self.inline_instances.insert(0, highlight_inline_instance)
        else:
            if highlight_found:
                self.inline_instances.pop(0)
        print self.inline_instances

    def change_view(self, request, object_id, form_url='', extra_context=None):
        self.regulate_highlight_inlines()
        return super(HighlightAdmin, self).change_view(request, object_id)

    def add_view(self, request, form_url='', extra_context=None):
        self.regulate_highlight_inlines()   
        return super(HighlightAdmin, self).add_view(request, form_url, extra_context)

In story/admin.py

class StoryAdmin(HighlightAdmin):

One thing to note is that I’m not merely manipulating inline classes(HighlightInline) but rather, I’m changing inline instances(HighlightInline(self.model, self.admin_site)). This is because django has already constructed a list of inline instances based on a list of inline classes during the initial construction of the admin class.

Another solution to Django 1.3

class BoxAdmin(admin.ModelAdmin):

    def change_view(self, request, object_id, form_url='', extra_context=None):
        self.inline_instances = [ItemChangeInline(self.model, self.admin_site)]
        return super(BoxAdmin, self).change_view(request, object_id, extra_context)

    def add_view(self, request, form_url='', extra_context=None):
        self.inline_instances = [ItemAddInline(self.model, self.admin_site)]
        return super(BoxAdmin, self).add_view(request, form_url, extra_context)

Inspired by you guys answer,
I was able to add more custom views to the admin.site.

Many times, just want add and change pages of different settings, not real extra views

# admin.py
class FooAdmin(admin.ModelAdmin):
    ....
    def edit_tag(self, obj):              # add a Link tag to change-list page
        return mark_safe('<a href="{}?edit=True">Edit</a>'.format(obj.get_absolute_url()))

    edit_tag.short_description = u'Extra Action'

    def change_view(self, request, object_id, form_url='', extra_context=None):
        if request.GET.get('edit', False):
            self.readonly_fields = (
                'total_amount',
            )
            self.inlines = []
        else:
            self.readonly_fields = (
                'name', 'client', 'constructor', 'total_amount'
            )
            self.inlines = [TransactionInline]
        return super(ProjectAdmin, self).change_view(request, object_id)

    def add_view(self, request, form_url='', extra_context=None):
        self.readonly_fields = (
            'total_amount',
        )
        self.inlines = []
        return super(ProjectAdmin, self).add_view(request)

After this I’ll have three views:

1. add view – without inline formset, no need to add related objects.
   

2. change view 1 – with inline formset, only for adding inline data(related objects), the the object’s field is readonly.
   

3. change view 2 – without inline formset, only for changing the object.
   

Really simple, and we can do more, thanks everyone.