Struct Tree 

pub struct Tree { /* private fields */ }

Tree widget for rendering hierarchical data.

Implementations

impl Tree

pub fn new(root: TreeNode) -> Self

Create a tree widget with the given root node.

pub fn with_show_root(self, show: bool) -> Self

Set whether to show the root node.

pub fn with_guides(self, guides: TreeGuides) -> Self

Set the guide character style.

pub fn with_guide_style(self, style: Style) -> Self

Set the style for guide characters.

pub fn with_label_style(self, style: Style) -> Self

Set the style for node labels.

pub fn with_root_style(self, style: Style) -> Self

Set the style for the root label.

pub fn with_persistence_id(self, id: impl Into<String>) -> Self

Set a persistence ID for state saving.

pub fn persistence_id(&self) -> Option<&str>

Get the persistence ID, if set.

pub fn hit_id(self, id: HitId) -> Self

Set a hit ID for mouse interaction.

pub fn with_search_query(self, query: impl Into<String>) -> Self

Apply a case-insensitive search query filter.

pub fn without_search_query(self) -> Self

Clear search filtering.

pub fn root(&self) -> &TreeNode

Get a reference to the root node.

pub fn root_mut(&mut self) -> &mut TreeNode

Get a mutable reference to the root node.

impl Tree

pub fn undo_id(&self) -> UndoWidgetId

Get the undo widget ID for this tree.

pub fn handle_key( &mut self, key: &KeyEvent, selected_visible_index: usize, ) -> bool

Handle keyboard navigation at the currently selected visible row.

Supported keys:

• Enter / Space: Toggle expand/collapse on the selected node.
• Right: Expand the selected node (if collapsed and has children).
• Left: Collapse the selected node (if expanded).

Returns true when an expand/collapse action was applied.

pub fn handle_mouse( &mut self, event: &MouseEvent, hit: Option<(HitId, HitRegion, u64)>, expected_id: HitId, ) -> MouseResult

Handle a mouse event for this tree.

Hit data convention

The hit data (u64) encodes the flattened visible row index. When the tree renders with a hit_id, each visible row registers HitRegion::Content with data = visible_row_index as u64.

Clicking a parent node (one with children) toggles its expanded state and returns Activated. Clicking a leaf returns Selected.

Arguments

• event — the mouse event from the terminal
• hit — result of frame.hit_test(event.x, event.y), if available
• expected_id — the HitId this tree was rendered with

pub fn node_at_visible_index_mut( &mut self, target: usize, ) -> Option<&mut TreeNode>

Get a mutable reference to the node at the given visible (flattened) index.

The traversal order matches render_node(): if show_root is true the root is row 0; otherwise children of the root are the top-level rows. Only expanded nodes’ children are visited.

Trait Implementations

impl Clone for Tree

fn clone(&self) -> Tree

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Tree

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Stateful for Tree

type State = TreePersistState

The state type that gets persisted.

fn state_key(&self) -> StateKey

Unique key identifying this widget instance.

fn save_state(&self) -> TreePersistState

Extract current state for persistence.

fn restore_state(&mut self, state: TreePersistState)

Restore state from persistence.

fn state_version() -> u32

State schema version for forward-compatible migrations.

impl TreeUndoExt for Tree

fn is_node_expanded(&self, path: &[usize]) -> bool

Check if a node is expanded.

fn expand_node(&mut self, path: &[usize])

Expand a node.

fn collapse_node(&mut self, path: &[usize])

Collapse a node.

impl UndoSupport for Tree

fn undo_widget_id(&self) -> UndoWidgetId

Get the widget’s unique ID for undo tracking.

fn create_snapshot(&self) -> Box<dyn Any + Send>

Create a snapshot of the current state for undo purposes.

fn restore_snapshot(&mut self, snapshot: &dyn Any) -> bool

Restore state from a snapshot.

impl Widget for Tree

fn render(&self, area: Rect, frame: &mut Frame<'_>)

Render the widget into the frame at the given area.

fn is_essential(&self) -> bool

Whether this widget is essential and should always render.