Questions & Answers

This error is occurring because the filer app is trying to use the CustomUser model in its admin interface, but it is not able to find a registered admin for that model. To fix this, you will need to create an admin class for your CustomUser model that is compatible with the filer app.

You can do this by subclassing filer.admin.permissionadmin.PermissionAdmin or filer.admin.folderadmin.FolderAdmin instead of the default admin.ModelAdmin class, and then registering your custom admin class with the CustomUser model.

For example, you can create a file named admin.py in your app directory and add the following code:

from django.contrib import admin
from filer.admin.folderadmin import FolderAdmin
from myapp.models import CustomUser

class CustomUserAdmin(FolderAdmin):
    pass

admin.site.unregister(CustomUser)
admin.site.register(CustomUser, CustomUserAdmin)

This code is creating a custom admin class CustomUserAdmin that inherits from filer.admin.folderadmin.FolderAdmin and then registering it to the CustomUser model using the admin.site.register() method.

You should also be aware that subclassing filer.admin.folderadmin.FolderAdmin also requires subclassing filer.admin.permissionadmin.PermissionAdmin, so you may need to create another custom admin class that inherit from filer.admin.permissionadmin.PermissionAdmin and register it to CustomUser as well.

Here is the code after update:

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from filer.admin.folderadmin import FolderAdmin
from myapp.models import CustomUser

class CustomUserAdmin(UserAdmin, FolderAdmin):
    pass

admin.site.unregister(CustomUser)
admin.site.register(CustomUser, CustomUserAdmin)

This code creates a custom admin class CustomUserAdmin that inherits from both UserAdmin and FolderAdmin and then register it to CustomUser model.

You may also need to do the same thing with PermissionAdmin if you experience any issues