Django: How to reference a context variable created in one class-based view from another class-based view

Question

In the simplified example below, how do I reference the context variable "Elephant" (created in the class Lion) from inside the class Leopard?

I have researched and tried a number of ways, including the last line below which results in a KeyError for "Elephant".

views.py

class Lion(ListView):
   
    def get_context_data(self, **kwargs):
        context super().get_context_data()
        context[“Elephant”] = Rhinoceros 
        context["Giraffe"] = Eagle
        return context

class Leopard(ListView):
    Buffalo = Lion.get_context_data(context[“Elephant”])

Answer 1

One option is to create your own ListView super class:

class AnimalListView(ListView):
    def get_context_data(self, *args, **kwargs):
        super().get_context_data(*args, **kwargs)
        return {
            "Elephant": Rhinoceros,
            "Giraffe": Eagle,
        }

Now your other list views can inherit this instead of inheriting form ListView directly:

class LionList(AnimalListView):
    ...

class LeopartList(AnimalListView):
    ...

Alternatively, you can make the class a mixin:

class AnimalContextMixin:
    def get_context_data(self, *args, **kwargs):
        super().get_context_data(*args, **kwargs)
        return {
            "Elephant": Rhinoceros,
            "Giraffe": Eagle,
        }

And then your list views should inherit from both ListView and this mixin:

class LionList(AnimalContextMixin, ListView):
    ...

class LeopartList(AnimalContextMixin, ListView):
    ...