Struct ScrollTree 

pub struct ScrollTree { /* private fields */ }

Directed graph of scrollable containers, keyed by DOM node index.

The parent chain defines how unconsumed scroll delta bubbles up. Rebuilt after each layout pass from the fragment tree.

Implementations

impl ScrollTree

pub fn new() -> Self

pub fn set(&mut self, dom_id: u32, node: ScrollNode)

pub fn get(&self, dom_id: u32) -> Option<&ScrollNode>

pub fn clear(&mut self)

Remove all nodes. Called before re-syncing from a new fragment tree.

pub fn contains(&self, dom_id: u32) -> bool

pub fn root_scroller(&self) -> Option<u32>

The root scroller — cached during set() / sync(). O(1).

pub fn chain(&self, start: u32) -> ScrollChain<'_>

Iterate the scroll chain from start toward the root scroller.

pub fn sync(&mut self, root: &Fragment)

Rebuild from the fragment tree. Finds all scrollable boxes and builds the parent-child scroll chain.

Chrome: ScrollTree::UpdateScrollTree() — runs after layout.

Trait Implementations

impl Clone for ScrollTree

fn clone(&self) -> ScrollTree

Returns a duplicate of the value.

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

Performs copy-assignment from source.