Tree

Added in version 0.6.0

A tree control widget.

• Focusable
• Container

Example

The example below creates a simple tree.

Outputtree.py

from textual.app import App, ComposeResult
from textual.widgets import Tree


class TreeApp(App):
    def compose(self) -> ComposeResult:
        tree: Tree[str] = Tree("Dune")
        tree.root.expand()
        characters = tree.root.add("Characters", expand=True)
        characters.add_leaf("Paul")
        characters.add_leaf("Jessica")
        characters.add_leaf("Chani")
        yield tree


if __name__ == "__main__":
    app = TreeApp()
    app.run()

Tree widgets have a "root" attribute which is an instance of a TreeNode. Call add() or add_leaf() to add new nodes underneath the root. Both these methods return a TreeNode for the child which you can use to add additional levels.

Reactive Attributes

Name	Type	Default	Description
show_root	bool	True	Show the root node.
show_guides	bool	True	Show guide lines between levels.
guide_depth	int	4	Amount of indentation between parent and child.

Messages

• Tree.NodeCollapsed
• Tree.NodeExpanded
• Tree.NodeHighlighted
• Tree.NodeSelected

Bindings

The tree widget defines the following bindings:

Key(s)	Description
enter	Select the current item.
space	Toggle the expand/collapsed state of the current item.
up	Move the cursor up.
down	Move the cursor down.

Component Classes

The tree widget provides the following component classes:

Class	Description
tree--cursor	Targets the cursor.
tree--guides	Targets the indentation guides.
tree--guides-hover	Targets the indentation guides under the cursor.
tree--guides-selected	Targets the indentation guides that are selected.
tree--highlight	Targets the highlighted items.
tree--highlight-line	Targets the lines under the cursor.
tree--label	Targets the (text) labels of the items.

---

Bases: Generic[TreeDataType], ScrollView

A widget for displaying and navigating data in a tree.

Parameters:

Name	Type	Description	Default
label	TextType	The label of the root node of the tree.	required
data	TreeDataType | None	The optional data to associate with the root node of the tree.	None
name	str | None	The name of the Tree.	None
id	str | None	The ID of the tree in the DOM.	None
classes	str | None	The CSS classes of the tree.	None
disabled	bool	Whether the tree is disabled or not.	False

BINDINGS class-attribute

BINDINGS = [
    Binding(
        "shift+left",
        "cursor_parent",
        "Cursor to parent",
        show=False,
    ),
    Binding(
        "shift+right",
        "cursor_parent_next_sibling",
        "Cursor to next ancestor",
        show=False,
    ),
    Binding(