Struct FocusRing 

pub struct FocusRing {
    pub order: Vec<AnnotId>,
    pub degenerate: bool,
}

The focus ring for one page, in traversal order.

degenerate reports that the banding could not make progress and the remainder was appended in index order — the recovery that replaces the oracle’s hang.

Fields

order: Vec<AnnotId>

The annotations, in traversal order.

degenerate: bool

Whether the banding degenerated.

Implementations

impl FocusRing

pub fn next(&self, current: AnnotId) -> Option<AnnotId>

The annotation after current, or None at the end.

Focus does not wrap: the last annotation has no next, which is what makes a fifth Tab across four fields report the event unconsumed.

pub fn prev(&self, current: AnnotId) -> Option<AnnotId>

The annotation before current, or None at the start.

pub fn first(&self) -> Option<AnnotId>

The first annotation, which a forward Tab from nothing lands on.

pub fn last(&self) -> Option<AnnotId>

The last annotation, which a backward Tab from nothing lands on.

That the two differ is the whole reason both exist: with nothing focused, forward and backward Tab land on different annotations, because the cursor starts between the ends rather than before them.

pub fn len(&self) -> usize

How many annotations are in the ring.

pub fn is_empty(&self) -> bool

Whether nothing is focusable.

Trait Implementations

impl Clone for FocusRing

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FocusRing

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

Formats the value using the given formatter.

impl PartialEq for FocusRing

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for FocusRing