Struct SelectionModel 

pub struct SelectionModel { /* private fields */ }

Index-based multi-selection state. Indices are opaque usizes the owning widget assigns to its items (typically the row/cell order).

Implementations

impl SelectionModel

pub fn new() -> SelectionModel

An empty selection.

pub fn is_empty(&self) -> bool

true when nothing is selected.

pub fn len(&self) -> usize

Number of selected indices.

pub fn is_selected(&self, index: usize) -> bool

Whether index is currently selected.

pub fn selected(&self) -> Vec<usize>

The selected indices in ascending order.

pub fn selected_set(&self) -> &BTreeSet<usize>

Borrow the selected set directly (ascending iteration order).

pub fn primary(&self) -> Option<usize>

The cursor / last-touched index, if any.

pub fn anchor(&self) -> Option<usize>

The current range anchor, if any.

pub fn remap_indices(&mut self, map: impl Fn(usize) -> Option<usize>)

Follow items when their owning collection changes row order. Map each old position to its new position, or None if the item disappeared. The cursor and range anchor remain independent of the selected set, including a cursor left on an item deselected by Ctrl-click.

pub fn clear(&mut self)

Drop everything — no selection, no anchor, no cursor.

pub fn replace_indices( &mut self, selected: impl IntoIterator<Item = usize>, primary: Option<usize>, )

Replace the selection after a model refresh while preserving the logical primary item. Callers map stable item identities to their new indices first; indices absent from selected cannot become primary.

pub fn select_only(&mut self, i: usize)

Replace the selection with the single index i. Resets the anchor and cursor to i. This is the plain-click / plain-arrow behaviour and the public primitive other code can call directly.

pub fn toggle(&mut self, i: usize)

Toggle i in/out of the selection (Ctrl-click). The anchor and cursor both move to i so a subsequent Shift gesture extends from here.

pub fn select_range_to(&mut self, i: usize, additive: bool)

Select the inclusive range from the anchor to i: unioned with the existing selection when additive (Ctrl+Shift), else replacing it (Shift). The anchor is preserved so repeated Shift gestures pivot around the same origin. Falls back to select_only when there is no anchor to extend from.

pub fn apply_click(&mut self, index: usize, ctrl: bool, shift: bool)

Apply a pointer click at index with the given modifier state. This is the one call most widgets need from a mouse handler.

pub fn move_to(&mut self, index: usize, extend: bool)

Move the keyboard cursor to index. With extend (Shift held) it grows the contiguous range from the anchor; otherwise it becomes a single selection. This is the one call most widgets need from a key handler after computing the target index.

pub fn select_all(&mut self, count: usize)

Select every index in 0..count. Anchor at 0, cursor at the last index. No-op for an empty range.

pub fn clamp_to(&mut self, count: usize) -> bool

Drop any selected/anchor/primary index that is >= count. Call this after the underlying item list shrinks (e.g. a directory change) so the model never points past the end. Returns true if anything was pruned.

Trait Implementations

impl Clone for SelectionModel

fn clone(&self) -> SelectionModel

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SelectionModel

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

Formats the value using the given formatter.

impl Default for SelectionModel

fn default() -> SelectionModel

Returns the “default value” for a type.

impl PartialEq for SelectionModel

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for SelectionModel

impl StructuralPartialEq for SelectionModel