Enum ScrollSource 

#[non_exhaustive]
pub enum ScrollSource {
    Unknown,
    Wheel,
    Finger,
    Momentum,
}

What is driving a WindowEvent::MouseWheel event.

This lets an application treat the different kinds of scrolling differently, for example to not scroll a slider during system-driven momentum scrolling, or to implement its own momentum scrolling only on platforms where the system doesn’t.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Unknown

The platform doesn’t say.

Wheel

A physical wheel, usually on a mouse (including tilting it sideways).

Finger

Fingers moving on a touchpad.

On platforms that report a TouchPhase, the fingers are on the touchpad from TouchPhase::Started until TouchPhase::Ended.

Momentum

The system is continuing a finger scroll after the fingers were lifted, with decaying speed, such as the “momentum phase” on macOS.

On platforms that report a TouchPhase, this gets its own TouchPhase::Started … TouchPhase::Ended cycle after the ScrollSource::Finger one.

Trait Implementations

impl Clone for ScrollSource

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ScrollSource

impl Debug for ScrollSource

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

Formats the value using the given formatter.

impl Eq for ScrollSource

impl Hash for ScrollSource

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ScrollSource

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ScrollSource