Enum fidl_fuchsia_ui_pointer::EventPhase

#[repr(u32)]
pub enum EventPhase {
    Add = 1,
    Change = 2,
    Remove = 3,
    Cancel = 4,
}

The possible states of a pointer event. These phases of events in a stream follow a state machine that starts with the ADD phase, followed by zero or more CHANGE phases, and finally terminates with REMOVE or CANCEL phase.

ADD ---> CHANGE* -+-> REMOVE
                  |
                  +-> CANCEL

A finite sequence of pointer events that follows this state machine, starting from the initial state, is called an interaction. A closed (or past) interaction is one where it has reached the terminal state; an open (or current) interaction is one where it has not.

For a given device pointer, a stream of events is observed as a succession of zero or more closed interactions (the past history of user engagement), followed by at most one open interaction (the current user engagement).

When we need to group pointer events by their interaction, an event carries an interaction id that is unique in that pointer stream. This common reference makes it possible to operate on a closed interaction, as well as an open interaction.

For example, touch events are typically observed as a succession of interactions, as fingers engage and disengage with the display.

Variants

Add = 1

The device has started tracking the pointer.

Change = 2

The device has reported an update to the pointer state.

Remove = 3

The device has stopped tracking the pointer.

Cancel = 4

The pointer is no longer available.

Implementations

impl EventPhase

pub fn from_primitive(prim: u32) -> Option<Self>

pub const fn into_primitive(self) -> u32

pub fn is_unknown(&self) -> bool

👎Deprecated: Strict enums should not use is_unknown

Trait Implementations

impl Clone for EventPhase

fn clone(&self) -> EventPhase

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for EventPhase

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

Formats the value using the given formatter.

impl Decode<EventPhase> for EventPhase

fn new_empty() -> Self

Creates a valid instance of Self. The specific value does not matter, since it will be overwritten by decode.

unsafe fn decode( &mut self, decoder: &mut Decoder<'_>, offset: usize, _depth: Depth ) -> Result<()>

Decodes an object of type T from the decoder’s buffers into self.

impl Encode<EventPhase> for EventPhase

unsafe fn encode( self, encoder: &mut Encoder<'_>, offset: usize, _depth: Depth ) -> Result<()>

Encodes the object into the encoder’s buffers. Any handles stored in the object are swapped for Handle::INVALID.

impl Hash for EventPhase

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 Ord for EventPhase

fn cmp(&self, other: &EventPhase) -> 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 + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for EventPhase

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for EventPhase

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

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl TypeMarker for EventPhase

type Owned = EventPhase

The owned Rust type which this FIDL type decodes into.

fn inline_align(_context: Context) -> usize

Returns the minimum required alignment of the inline portion of the encoded object. It must be a (nonzero) power of two.

fn inline_size(_context: Context) -> usize

Returns the size of the inline portion of the encoded object, including padding for alignment. Must be a multiple of inline_align.

fn encode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and encoding requires no validation. When true, we can optimize encoding arrays and vectors of Self::Owned to a single memcpy.

fn decode_is_copy() -> bool

Returns true if the memory layout of Self::Owned matches the FIDL wire format and decoding requires no validation. When true, we can optimize decoding arrays and vectors of Self::Owned to a single memcpy.

impl ValueTypeMarker for EventPhase

type Borrowed<'a> = EventPhase

The Rust type to use for encoding. This is a particular Encode<Self> type cheaply obtainable from &Self::Owned. There are three cases:

fn borrow<'a>(value: &'a <Self as TypeMarker>::Owned) -> Self::Borrowed<'a>

Cheaply converts from &Self::Owned to Self::Borrowed.

impl Copy for EventPhase

impl Eq for EventPhase

impl StructuralPartialEq for EventPhase