admin.py 文件源码

def field_choices(self, field, request, model_admin):
        mptt_level_indent = getattr(model_admin, 'mptt_level_indent', self.mptt_level_indent)
        language_bidi = get_language_bidi()
        initial_choices = field.get_choices(include_blank=False)
        pks = [pk for pk, val in initial_choices]
        models = field.related_model._default_manager.filter(pk__in=pks)
        levels_dict = {model.pk: getattr(model, model._mptt_meta.level_attr) for model in models}
        choices = []
        for pk, val in initial_choices:
            padding_style = ' style="padding-%s:%spx"' % (
                'right' if language_bidi else 'left',
                mptt_level_indent * levels_dict[pk])
            choices.append((pk, val, mark_safe(padding_style)))
        return choices

    # Ripped from contrib.admin.filters,RelatedFieldListFilter Django 1.8 to
    # yield padding_style