Struct UseVirtualList 

pub struct UseVirtualList {
    pub scroll_offset: Signal<i32>,
    pub viewport_height: Signal<i32>,
}

Reactive state for the virtual list scroll tracking.

Contains only Copy signal fields so the struct can be freely captured inside html! closures without causing FnOnce issues.

Fields

scroll_offset: Signal<i32>

The current scroll offset in pixels.

viewport_height: Signal<i32>

The current viewport height in pixels.

Implementations

impl UseVirtualList

Implementation of virtual list functionality.

pub fn use_scroll_state() -> UseVirtualList

Creates virtual list state signals for tracking scroll offset and viewport height.

Returns

• UseVirtualList - The virtual list state containing scroll offset and viewport height signals.

pub fn on_scroll(self) -> Option<Rc<dyn Fn(Event)>>

Creates a scroll event handler that tracks the container scroll position and viewport height.

Reads scrollTop and clientHeight from the scroll container element referenced by VIRTUAL_LIST_CONTAINER_ID and updates the corresponding signals.

Returns

• Option<Rc<dyn Fn(Event)>> - A scroll handler for the virtual list container.

pub fn update_viewport_height(self)

Reads the container clientHeight and writes it to the viewport height signal.

Should only be called when the DOM is already present (e.g. inside a resize callback or after the first paint). For initial mount use schedule_measure instead.

pub fn schedule_measure(self)

Schedules a viewport height measurement on the next animation frame.

Uses an atomic guard to ensure only one measurement is pending at a time — if a previous callback hasn’t fired yet, subsequent calls are silently ignored. This prevents accumulating redundant animation-frame callbacks when the component re-renders frequently.

pub fn try_get_container() -> Option<Element>

Returns the virtual list container element by its default id.

Returns

• Option<Element> - The container element, if found in the document.

pub fn try_get_container_by_id<C>(container_id: C) -> Option<Element>

where C: AsRef<str>,

Returns the virtual list container element by its id.

Arguments

• C: AsRef<str> - The container element id.

Returns

• Option<Element> - The container element, if found in the document.

impl UseVirtualList

pub fn get_scroll_offset(&self) -> Signal<i32>

pub fn get_mut_scroll_offset(&mut self) -> &mut Signal<i32>

pub fn set_scroll_offset(&mut self, val: Signal<i32>) -> &mut Self

pub fn get_viewport_height(&self) -> Signal<i32>

pub fn get_mut_viewport_height(&mut self) -> &mut Signal<i32>

pub fn set_viewport_height(&mut self, val: Signal<i32>) -> &mut Self

impl UseVirtualList

pub fn new(scroll_offset: Signal<i32>, viewport_height: Signal<i32>) -> Self

Trait Implementations

impl Clone for UseVirtualList

fn clone(&self) -> UseVirtualList

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for UseVirtualList

impl Debug for UseVirtualList

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

Formats the value using the given formatter.

impl Default for UseVirtualList

fn default() -> UseVirtualList

Returns the “default value” for a type.

impl Eq for UseVirtualList

impl Ord for UseVirtualList

fn cmp(&self, other: &UseVirtualList) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for UseVirtualList

fn eq(&self, other: &UseVirtualList) -> 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 PartialOrd for UseVirtualList

fn partial_cmp(&self, other: &UseVirtualList) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for UseVirtualList