Struct OutlinerState 

pub struct OutlinerState<Id>
where
    Id: Hash + Eq + Clone + Send + Sync,
{ /* private fields */ }

State for an outliner widget instance.

This struct tracks which collection nodes are expanded and which node (if any) is currently being edited. The state is generic over the node ID type and integrates with egui’s memory system for automatic persistence.

Type Parameters

• Id - The type used to identify nodes. Must implement Hash, Eq, and Clone.

Examples

use egui_arbor::OutlinerState;
use std::collections::HashSet;

let mut state = OutlinerState::<String>::default();
 
// Toggle expansion state
state.toggle_expanded(&"node1".to_string());
assert!(state.is_expanded(&"node1".to_string()));

// Start editing a node
state.start_editing("node2".to_string(), "Node 2".to_string());
assert!(state.is_editing(&"node2".to_string()));

Implementations

impl<Id> OutlinerState<Id>

where Id: Hash + Eq + Clone + Send + Sync,

pub fn load(ctx: &Context, id: Id) -> Self

where Id: 'static,

Loads the outliner state from egui’s memory system.

If no state exists for the given ID, returns a default empty state.

Parameters

• ctx - The egui context to load state from
• id - The unique identifier for this outliner instance

Examples

let state = OutlinerState::<String>::load(ctx, egui::Id::new("my_outliner"));

pub fn store(&self, ctx: &Context, id: Id)

where Id: 'static,

Stores the outliner state to egui’s memory system.

The state will be persisted across frames and can be retrieved using load with the same ID.

Parameters

• ctx - The egui context to store state in
• id - The unique identifier for this outliner instance

Examples

let mut state = OutlinerState::<String>::default();
state.toggle_expanded(&"node1".to_string());
state.store(ctx, egui::Id::new("my_outliner"));

pub fn is_expanded(&self, id: &Id) -> bool

Checks if a node is currently expanded.

Parameters

• id - The ID of the node to check

Returns

true if the node is expanded, false otherwise.

Examples

let mut state = OutlinerState::<String>::default();
state.set_expanded(&"node1".to_string(), true);
assert!(state.is_expanded(&"node1".to_string()));

pub fn toggle_expanded(&mut self, id: &Id)

Toggles the expansion state of a node.

If the node is currently expanded, it will be collapsed. If the node is currently collapsed, it will be expanded.

Parameters

• id - The ID of the node to toggle

Examples

let mut state = OutlinerState::<String>::default();
state.toggle_expanded(&"node1".to_string());
assert!(state.is_expanded(&"node1".to_string()));
state.toggle_expanded(&"node1".to_string());
assert!(!state.is_expanded(&"node1".to_string()));

pub fn set_expanded(&mut self, id: &Id, expanded: bool)

Sets the expansion state of a node.

Parameters

• id - The ID of the node to modify
• expanded - true to expand the node, false to collapse it

Examples

let mut state = OutlinerState::<String>::default();
state.set_expanded(&"node1".to_string(), true);
assert!(state.is_expanded(&"node1".to_string()));
state.set_expanded(&"node1".to_string(), false);
assert!(!state.is_expanded(&"node1".to_string()));

pub fn is_editing(&self, id: &Id) -> bool

Checks if a node is currently being edited.

Parameters

• id - The ID of the node to check

Returns

true if the node is being edited, false otherwise.

Examples

let mut state = OutlinerState::<String>::default();
state.start_editing("node1".to_string(), "Node 1".to_string());
assert!(state.is_editing(&"node1".to_string()));

pub fn start_editing(&mut self, id: Id, initial_text: String)

Starts editing a node.

This will stop editing any previously edited node, as only one node can be edited at a time.

Parameters

• id - The ID of the node to start editing
• initial_text - The initial text to display in the edit field

Examples

let mut state = OutlinerState::<String>::default();
state.start_editing("node1".to_string(), "Initial Name".to_string());
assert!(state.is_editing(&"node1".to_string()));

pub fn stop_editing(&mut self)

Stops editing the currently edited node, if any.

Examples

let mut state = OutlinerState::<String>::default();
state.start_editing("node1".to_string(), "Name".to_string());
state.stop_editing();
assert!(!state.is_editing(&"node1".to_string()));

pub fn editing_text_mut(&mut self) -> &mut String

Returns a mutable reference to the editing text.

This allows the text edit widget to modify the text directly.

pub fn editing_text(&self) -> &str

Returns a reference to the editing text.

pub fn drag_drop(&self) -> &DragDropState<Id>

Returns a reference to the drag-drop state.

Examples

let state = OutlinerState::<String>::default();
assert!(!state.drag_drop().is_dragging());

pub fn drag_drop_mut(&mut self) -> &mut DragDropState<Id>

Returns a mutable reference to the drag-drop state.

Examples

let mut state = OutlinerState::<String>::default();
state.drag_drop_mut().start_drag("node1".to_string());
assert!(state.drag_drop().is_dragging());

pub fn set_last_selected(&mut self, id: Option<Id>)

Sets the last selected node for shift-click range selection.

Parameters

• id - The ID of the last selected node

pub fn last_selected(&self) -> Option<&Id>

Returns the ID of the last selected node, if any.

pub fn start_box_selection(&mut self, start_pos: Pos2)

Starts a box selection operation.

Parameters

• start_pos - The starting position in screen coordinates

pub fn box_selection(&self) -> Option<&BoxSelectionState>

Returns the current box selection state, if any.

pub fn end_box_selection(&mut self)

Ends the current box selection operation.

pub fn set_dragging_nodes(&mut self, nodes: Vec<Id>)

Sets the nodes being dragged in a multi-drag operation.

pub fn dragging_nodes(&self) -> &[Id]

Returns the nodes being dragged in a multi-drag operation.

pub fn clear_dragging_nodes(&mut self)

Clears the dragging nodes list.

Trait Implementations

impl<Id> Clone for OutlinerState<Id>

where Id: Hash + Eq + Clone + Send + Sync + Clone,

fn clone(&self) -> OutlinerState<Id>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<Id> Debug for OutlinerState<Id>

where Id: Hash + Eq + Clone + Send + Sync + Debug,

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

Formats the value using the given formatter.

impl<Id> Default for OutlinerState<Id>

where Id: Hash + Eq + Clone + Send + Sync,

fn default() -> Self

Creates a new outliner state with no expanded nodes and no editing node.