textual/docs/widgets/tree.md

Tree

A tree control widget.

• Focusable
• Container

Example

The example below creates a simple tree.

=== "Output"

```{.textual path="docs/examples/widgets/tree.py"}
```

=== "tree.py"

```python
--8<-- "docs/examples/widgets/tree.py"
```

Tree widgets have a "root" attribute which is an instance of a [TreeNode][textual.widgets.tree.TreeNode]. Call [add()][textual.widgets.tree.TreeNode.add] or [add_leaf()][textual.widgets.tree,TreeNode.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

NodeSelected

The Tree.NodeSelected message is sent when the user selects a tree node.

Attributes

attribute	type	purpose
node	[TreeNode][textual.widgets.tree.TreeNode]	Selected node.

NodeExpanded

The Tree.NodeExpanded message is sent when the user expands a node in the tree.

Attributes

attribute	type	purpose
node	[TreeNode][textual.widgets.tree.TreeNode]	Expanded node.

NodeCollapsed

The Tree.NodeCollapsed message is sent when the user expands a node in the tree.

Attributes

attribute	type	purpose
node	[TreeNode][textual.widgets.tree.TreeNode]	Collapsed node.

See Also

• [Tree][textual.widgets.Tree] code reference
• [TreeNode][textual.widgets.tree.TreeNode] code reference