Tree Widget

The Tree Widget is a powerful UI component used to visualize and interact with hierarchical data structures—like categories in a product catalog.

💡 Example: Tree Widget for Treebeard Categories

This guide walks you through setting up a Tree Widget for a hierarchical model using treebeard.MP_Node, such as your Category model.

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Prerequisites: Category Model

Your Category model must inherit from MP_Node and define path, which is used by treebeard.

models.py

from treebeard.mp_tree import MP_Node
from project.core.models import BaseDomainModel

class Category(BaseDomainModel, MP_Node):
    path = models.CharField(max_length=255)
    order_by = models.PositiveIntegerField(default=0)
    is_active = models.BooleanField(default=True, verbose_name="Is active")
    name = models.CharField(max_length=200)
    slug = models.SlugField(unique=True)
    image = models.ImageField(upload_to="categories", null=True, blank=True)

    def __str__(self):
        return self.name

    class Meta:
        verbose_name = "Category"
        verbose_name_plural = "Categories"

🛠️ Step-by-Step Setup

1. Define a Tree Widget

Create a custom widget by subclassing SBAdminTreeWidget.

catalog/sb_admin_widgets.py

from django_smartbase_admin.admin.widgets import SBAdminTreeWidget
from .models import Category

class CategoryTreeWidget(SBAdminTreeWidget):
    model = Category
    order_by = ["path"]

    @classmethod
    def get_tree_base_values(cls):
        return ["id", "path", "name"]

    @classmethod
    def get_tree_title(cls, request, item):
        return item.get("name")

    @classmethod
    def get_label(cls, request, item):
        return item.name

2. Enable Tree View in Admin List

Update your admin to use a tree list view with reorder support.

catalog/sb_admin.py

@admin.register(Category, site=sb_admin_site)
class CategorySBAdmin(SBAdmin):
    model = Category
    change_list_template = "sb_admin/actions/tree_list.html"
    sbadmin_list_display = ("name",)
    sbadmin_list_display_data = ["depth", "path"]
    sbadmin_list_reorder_field = "path"
    ordering = ["path"]
    use_tree_ordering = True

    def get_extra_context(self, request, extra_context=None):
        extra_context = extra_context or {}
        extra_context["tree_strings"] = CategoryTreeWidget.tree_strings
        extra_context["tree_json_url"] = self.get_action_url("tree_list_json")
        return extra_context

Use Tree Selector in Inlines

Allow users to select categories via an interactive tree in a form or inline

catalog/sb_admin_forms.py

from django import forms
from django_smartbase_admin.admin.admin_base import SBAdminBaseForm
from .models import Product, Category
from .sb_admin_widgets import CategoryTreeWidget

class ProductCategoryTreeInlineForm(SBAdminBaseForm):
    category = forms.ModelMultipleChoiceField(
        queryset=Category.objects.all(),
        required=False,
        label="Category",
        to_field_name="path",  # required for MP_Node trees
        widget=CategoryTreeWidget(inline=True, multiselect=True, value_field="path"),
    )

    class Meta:
        model = Product
        fields = ["category"]

Plug it into a fake inline:

catalog/sb_admin.py

class ProductCategoryTreeInline(SBAdminFakeInlineMixin, SBAdminTableInline):
    model = Product
    form = ProductCategoryTreeInlineForm
    title = _("Categories - Tree Widget example")

    def has_add_permission(self, request, obj=None):
        return False

    def filter_fake_inline_identifier_by_parent_instance(self, inline_queryset, parent_instance):
        return inline_queryset.filter(pk=parent_instance.id)

You can learn more about Fake Inlines in 🔗Fake inlines section.

Tree Filter Widget

The Tree Filter Widget enables users to filter data using hierarchical structures such as categories, departments etc...

💡 Example: Category Tree Filter for Product SBAdmin View

1. Create widget

Create a filter-specific widget by combining the base tree widget and SBAdminTreeFilterWidget:

catalog/sb_admin_widgets.py

class CategoryTreeFilterWidget(CategoryTreeWidget, SBAdminTreeFilterWidget):
    template_name = "sb_admin/filter_widgets/tree_select_filter.html"

2. Add the Filter to Your Admin

Use the custom widget in a SBAdminField in your admin class to enable tree-based filtering:

catalog/sb_admin.py

python title="catalog/sb_admin.py"
@admin.register(Product, site=sb_admin_site)
class ProductSBAdmin(SBAdmin):
    model = Product
    sbadmin_list_display = (
         # ... Other fields
        SBAdminField(
            name="categories",
            title="Categories",
            annotate="categories__name",
            filter_widget=CategoryTreeFilterWidget(
                search_query_lambda=lambda request, qs, model, search_term, language_code: qs.filter(
                    name__icontains=search_term
                ),
                filter_query_lambda=lambda request, filter_value: Q(
                    is_active=True
                ),
            ),
        ),
    )

⚙️ Key Options

• multiselect: True for multiple selections, False for single.
• value_field: Typically "path" for MP_Node trees.
• search_query_lambda: Optional search support inside the tree.
• filter_query_lambda: Filter values in widget.