Django Admin: Using a custom widget for only one model field

I have a DateTimeField field in my model. I wanted to display it as a checkbox widget in the Django admin site. To do this, I created a custom form widget. However, I do not know how to use my custom widget for only this one field.

The Django documentation explains how to use a custom widget for all fields of a certain type:

class StopAdmin(admin.ModelAdmin):
    formfield_overrides = {
        models.DateTimeField: {'widget': ApproveStopWidget }
    }

This is not granular enough though. I want to change it for only one field.

Create a custom ModelForm for your ModelAdmin and add 'widgets' to its Meta class, like so:

class StopAdminForm(forms.ModelForm):
  class Meta:
    model = Stop
    widgets = {
      'field_name': ApproveStopWidget(),
    }
    fields = '__all__'

class StopAdmin(admin.ModelAdmin):
  form = StopAdminForm

Done!

Documentation for this is sort of non-intuitively placed in the ModelForm docs, without any mention to it given in the admin docs. See: Creating forms from models