Enum Field 

pub enum Field {
    Variable(VariableField),
    Array(ArrayField),
    Constant(ConstantField),
}

A single field inside a Report.

Fields may be Variable and represent a single element of data or they may be a Array that represent multiple elements.

Fields of type Constant should be ignored by the caller.

Given a set of bytes that is a HID Report use VariableField::extract() or ArrayField::extract() to extract the value for this field, for example:

  let val = field.extract(bytes).unwrap();
  if val.is_signed() {
    let unsigned: u32 = val.into();
  } else {
    let signed: i32 = val.into();
  }

Variants

Variable(VariableField)

A single element of data

Array(ArrayField)

A set of multiple fields

Constant(ConstantField)

Padding

Implementations

impl Field

pub fn id(&self) -> FieldId

Return the unique (within this report descriptor) ID for this field.

The FieldId does not exist in the actual ReportDescriptor, it is a unique ID assigned by this crate to later identify a given field for data extraction and/or further parsing.

pub fn bits(&self) -> &Range<usize>

Returns the bit range that make up this field.

pub fn collections(&self) -> &[Collection]

Return the set of collections this Field belongs to or the empty slice.

Trait Implementations

impl Clone for Field

fn clone(&self) -> Field

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Field

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

Formats the value using the given formatter.