Struct RowMotions 

pub struct RowMotions<K> { /* private fields */ }

The rows of a virtualized list or table on their way after a change the person just made (motion::ListChange): the owner notes where its shown rows stand before the change (Self::capture), and the next frame moves the survivors from there to where they are laid out now and fades arrivals in (Self::start). Only rows shown after the change move; nothing outside the viewport animates. A change nobody just asked for (a sync), a shortcut’s result and reduced motion land at once.

Implementations

impl<K> RowMotions<K>

where K: Clone + Eq + Hash,

pub fn fading_out_leavers(self) -> RowMotions<K>

Rows a change takes out of the shown ones fade out where they stood (Self::leaving): an owner that keeps what they showed paints them, as a tree does the rows a collapse folds away.

pub fn caused_by_hand(now: Instant, reduce_motion: bool) -> Option<MotionSource>

The input a change happening at now moves for: the person’s pointer or finger, a few hundred milliseconds ago. None when nobody just made it, when a key or an action did (its result lands), or under reduced motion (a list is read, not watched).

pub fn capture( &mut self, before: impl IntoIterator<Item = (K, f64)>, arrivals_fade: bool, source: Option<MotionSource>, )

Before a structural change: note where the shown rows stand (before, each row’s top). With no source (see Self::caused_by_hand) the change lands at once. Two changes before a frame move the rows from where the first found them.

pub fn cancel(&mut self)

Forget a change noted but not started: it lands at once.

pub fn has_pending(&self) -> bool

Whether a change waits for the next frame to start moving.

pub fn start( &mut self, shown: impl IntoIterator<Item = (K, f64)>, motion: EffectiveMotion, now: Instant, )

Start the motion of a change noted before this frame, for the rows shown now (shown, each row’s laid-out top), and forget rows that have arrived. A row already moving continues from where it is drawn. Asks the frame pump for frames until the last one rests.

pub fn settle(&mut self, now: Instant)

Forget the rows that have arrived and the ones that have faded out.

pub fn leaving(&self, now: Instant) -> impl Iterator<Item = (&K, f64, f32)>

The rows fading out where they stood at now: each one’s key, its top before the change and its opacity.

pub fn clear(&mut self)

Forget every row’s motion: they all stand where they are laid out.

pub fn get(&self, key: &K) -> Option<&RowMotion>

The motion of the row keyed key, while it has one.

pub fn pose(&self, key: &K, now: Instant) -> (f64, f32)

Where the row keyed key is drawn at now: how far below its laid-out place, and its opacity. (0, 1) for a row at rest.

pub fn is_empty(&self) -> bool

Whether no row is on its way.

pub fn is_moving(&self, now: Instant) -> bool

Whether any row is still moving at now (its owner asks for frames).

Trait Implementations

impl<K> Default for RowMotions<K>

fn default() -> RowMotions<K>

Returns the “default value” for a type.