Struct TreeNav 

pub struct TreeNav { /* private fields */ }

Tree navigation with collapsible sections

Handles navigation logic for hierarchical tree structures where parent nodes can be collapsed to hide their children.

Example

let mut nav = TreeNav::new();
nav.add_item(TreeItem::new(0).collapsible());  // Section
nav.add_item(TreeItem::new(1).with_parent(0)); // Child
nav.add_item(TreeItem::new(2).with_parent(0)); // Child

nav.next();  // Move to next visible item
nav.toggle_collapse();  // Collapse/expand current item

Implementations

impl TreeNav

pub fn new() -> Self

Create a new empty tree navigation

pub fn add_item(&mut self, item: TreeItem)

Add an item to the tree

pub fn clear(&mut self)

Clear all items

pub fn selected(&self) -> usize

Get current selection

pub fn selected_row(&self) -> usize

Get current row within selected item

pub fn is_collapsed(&self, id: usize) -> bool

Check if an item is collapsed

pub fn is_visible(&self, id: usize) -> bool

Check if an item is visible (not hidden by collapsed parent)

pub fn visible_items(&self) -> Vec<&TreeItem>

Get visible items

pub fn next(&mut self)

Move to next visible item

pub fn prev(&mut self)

Move to previous visible item

pub fn next_item(&mut self)

Move to next item (skip rows within item)

pub fn prev_item(&mut self)

Move to previous item (skip rows within item)

pub fn toggle_collapse(&mut self)

Toggle collapse state of current item

pub fn collapse(&mut self)

Collapse current item

pub fn expand(&mut self)

Expand current item

pub fn collapse_all(&mut self)

Collapse all collapsible items

pub fn expand_all(&mut self)

Expand all items

pub fn select(&mut self, id: usize)

Set selection by id

pub fn first(&mut self)

Go to first visible item

pub fn last(&mut self)

Go to last visible item

pub fn get_prefix(&self, id: usize) -> (String, bool)

Get tree prefix for an item

Automatically calculates the correct prefix based on item’s position in the tree hierarchy.

Arguments

• id - Item id to get prefix for

Returns

Tuple of (prefix_string, is_last)

pub fn is_last_sibling(&self, id: usize) -> bool

Check if item is the last visible sibling at its level

pub fn render_items(&self) -> Vec<(&TreeItem, String, bool)>

Get all visible items with their prefixes for rendering

Returns Vec of (item_ref, prefix_string, is_selected)

Trait Implementations

impl Default for TreeNav

fn default() -> Self

Returns the “default value” for a type.