Struct SelectData 

pub struct SelectData { /* private fields */ }

The selectedness of a <select> element’s list of options, plus whether its drop-down is showing.

Positions, not node ids. selectedIndex is the spec’s own handle on an option, and a position cannot dangle the way a stored id does once the option is removed from the tree. The list of options itself is recomputed from the subtree on every read, so a stale position is at worst out of range rather than pointing at some unrelated node.

A Vec<bool> rather than a single index because <select multiple> can have any number of options selected at once, and a single index would make the multiple case unrepresentable rather than merely unsupported.

Implementations

impl SelectData

pub fn new(selected: Vec<bool>) -> Self

Seed the state with one entry per option, in the select’s list order.

pub fn resize(&mut self, len: usize)

Grow or shrink to len options, keeping the selectedness of the options that are still there.

Layout construction runs again on every resolve, so this is the only place a script-added <option> gets an entry of its own. Re-seeding from the selected content attributes instead would throw away whatever the user had actually chosen the moment anything else on the page changed.

pub fn len(&self) -> usize

The number of options the state has entries for.

pub fn is_empty(&self) -> bool

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

Whether the option at index is selected. Out of range reads false.

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

The first selected option, which is selectedIndex for a single select.

pub fn set_selected(&mut self, index: usize, selected: bool) -> bool

Set one option’s selectedness without touching the others. Returns whether it changed.

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

Select index and clear every other option. Returns whether anything changed.

pub fn clear_selection(&mut self) -> bool

Deselect every option. Returns whether anything changed.

pub fn is_open(&self) -> bool

Whether the drop-down list is showing.

pub fn set_open(&mut self, open: bool)

Trait Implementations

impl Clone for SelectData

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 SelectData

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

Formats the value using the given formatter.

impl Default for SelectData

fn default() -> Self

Returns the “default value” for a type.

impl Eq for SelectData

impl PartialEq for SelectData

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for SelectData