Trait FieldAttributes 

pub trait FieldAttributes {
    // Required methods
    fn is_relative(&self) -> bool;
    fn wraps(&self) -> bool;
    fn is_nonlinear(&self) -> bool;
    fn has_no_preferred_state(&self) -> bool;
    fn has_null_state(&self) -> bool;
    fn is_buffered_bytes(&self) -> bool;
    fn is_volatile(&self) -> Option<bool>;

    // Provided methods
    fn is_absolute(&self) -> bool { ... }
    fn does_not_wrap(&self) -> bool { ... }
    fn is_linear(&self) -> bool { ... }
    fn has_preferred_state(&self) -> bool { ... }
    fn has_no_null_state(&self) -> bool { ... }
    fn is_bitfield(&self) -> bool { ... }
    fn is_nonvolatile(&self) -> Option<bool> { ... }
}

Field attributes, see Main Data Item in Section 6.2.5.

These properties come in pairs (bit set or unset in the HID report descriptor item), for readability in the caller, a function is provided for each state.

Required Methods

fn is_relative(&self) -> bool

True if the data is relative compared to a previous report

Mutually exclusive with FieldAttributes::is_absolute.

fn wraps(&self) -> bool

True if the data wraps around at the logical minimum/maximum (e.g. a dial that can spin at 360 degrees).

Mutually exclusive with FieldAttributes::does_not_wrap.

fn is_nonlinear(&self) -> bool

True if the data was pre-processed on the device and the logical range is not linear.

Mutually exclusive with FieldAttributes::is_linear.

fn has_no_preferred_state(&self) -> bool

True if the control does not have a preferred state it returns to when the user stops interacting (e.g. a joystick may return to a neutral position)

Mutually exclusive with FieldAttributes::has_preferred_state.

fn has_null_state(&self) -> bool

True if the control has a null state where it does not send data (e.g. a joystick in neutral state)

Mutually exclusive with FieldAttributes::has_no_null_state.

fn is_buffered_bytes(&self) -> bool

True if the control emits a fixed size stream of bytes.

Mutually exclusive with FieldAttributes::is_bitfield.

fn is_volatile(&self) -> Option<bool>

Indiciates whether control should be changed by the host. Volatile fields can change without host interactions.

This attribute is only available on a Field in an OutputReport or an FeatureReport. It is always None for fields in an InputReport.

Provided Methods

fn is_absolute(&self) -> bool

True if the data is absolute

Mutually exclusive with FieldAttributes::is_relative.

fn does_not_wrap(&self) -> bool

True if the data does not wrap at the logical minimum/maximum.

Mutually exclusive with FieldAttributes::wraps.

fn is_linear(&self) -> bool

True if the data was not pre-processed on the device and the logical range is linear.

Mutually exclusive with FieldAttributes::is_nonlinear.

fn has_preferred_state(&self) -> bool

True if the control has a preferred state it returns to when the user stops interacting (e.g. a joystick may return to a neutral position)

Mutually exclusive with FieldAttributes::has_no_preferred_state.

fn has_no_null_state(&self) -> bool

True if the control does not have a null state where it does not send data.

Mutually exclusive with FieldAttributes::has_null_state.

fn is_bitfield(&self) -> bool

True if the control is a single bit field (value).

Mutually exclusive with FieldAttributes::is_buffered_bytes.

fn is_nonvolatile(&self) -> Option<bool>

Indiciates whether control should be changed by the host. Volatile fields can change without host interactions.

This attribute is only available on a Field in an OutputReport or an FeatureReport. It is always None for fields in an InputReport.

Implementors

impl FieldAttributes for ArrayField

impl FieldAttributes for VariableField