Struct FocusController 

pub struct FocusController {
    pub focus: NodeId,
    pub history: Vec<NodeId>,
    pub candidates: Vec<Candidate>,
    pub selection: usize,
    /* private fields */
}

Fields

focus: NodeId

history: Vec<NodeId>

candidates: Vec<Candidate>

selection: usize

Implementations

impl FocusController

pub fn new(focus: NodeId, provider: &dyn DataProvider, limit: usize) -> Self

pub fn focus_on(&mut self, id: NodeId, provider: &dyn DataProvider)

pub fn is_pending(&self) -> bool

Whether the candidate list is currently just a pending placeholder — the neighborhood was requested but hadn’t arrived when it was last fetched.

pub fn refetch(&mut self, provider: &dyn DataProvider)

Re-run the fetch for the current focus without disturbing focus/history. Called after an async cache fill resolves a neighborhood that was pending when this controller first fetched it; the provider now returns real data.

pub fn select(&mut self, delta: i32)

pub fn select_index(&mut self, i: usize) -> bool

Move the selection to candidate i. Returns false — changing nothing — when i is out of range or the candidate is a Loading placeholder (inert by design, same as hit-testing). The id→index resolution lives in graph-explorer-wasm, which mints the scene ids; this method is deliberately just the bounds-checked cursor move.

pub fn candidates(&self) -> &[Candidate]

Read-only view for hosts that resolve ids/indices — graph-explorer-wasm’s select_id.

pub fn descend(&mut self, provider: &dyn DataProvider) -> DescendOutcome

pub fn selected(&self) -> Option<SelectionInfo>

What is selected right now, or None when there are no candidates.

pub fn back(&mut self, provider: &dyn DataProvider)