Systemic::BluetoothLE::Characteristic Class Reference

Represents a service's characteristic of a Bluetooth Low Energy (BLE) peripheral. More...

#include <Characteristic.h>

Public Member Functions
Destructor
	~Characteristic ()
	Destroys the Characteristic instance.
Getters
std::uint16_t	handle () const
	Gets the 16 bits handle of the BLE characteristic.
winrt::guid	uuid () const
	Gets the UUID of the characteristic.
std::underlying_type< CharacteristicProperties >::type	properties () const
	Gets the standard BLE properties of the characteristic.
bool	canWrite () const
	Indicates whether the characteristic can be written.
bool	canRead () const
	Indicates whether the characteristic can be read.
bool	canNotify () const
	Indicates whether the characteristic can notify its value changes.

Characteristic operations
std::future< std::vector< std::uint8_t > >	readValueAsync ()
	Reads the value from the characteristic.
std::future< BleRequestStatus >	writeAsync (const std::vector< std::uint8_t > &data, bool withoutResponse=false)
	Writes the given data to the value of the characteristic.
std::future< BleRequestStatus >	subscribeAsync (const std::function< void(const std::vector< std::uint8_t > &)> &onValueChanged)
	Subscribes for value changes of the characteristic.
std::future< BleRequestStatus >	unsubscribeAsync ()
	Unsubscribes from value changes of the characteristic.

Detailed Description

Represents a service's characteristic of a Bluetooth Low Energy (BLE) peripheral.

A characteristic may be queried for its properties, and its underlying value may be read and/or written depending on the characteristic's capabilities. A characteristic with the notifiable property may be subscribed to get notified when its value changes.

Those operations are asynchronous and return a std::future.

The Characteristic class internally stores a WinRT's GattCharacteristic object.

Member Function Documentation

canNotify()

bool Systemic::BluetoothLE::Characteristic::canNotify

(

)

const

Indicates whether the characteristic can notify its value changes.

Returns

Whether the characteristic can notify.

canRead()

bool Systemic::BluetoothLE::Characteristic::canRead

(

)

const

Indicates whether the characteristic can be read.

Returns

Whether the characteristic can be read.

canWrite()

bool Systemic::BluetoothLE::Characteristic::canWrite

(

)

const

Indicates whether the characteristic can be written.

Returns

Whether the characteristic can be written.

handle()

std::uint16_t Systemic::BluetoothLE::Characteristic::handle

(

)

const

Gets the 16 bits handle of the BLE characteristic.

Returns

The 16 bits handle of the characteristic.

properties()

std::underlying_type< CharacteristicProperties >::type Systemic::BluetoothLE::Characteristic::properties

(

)

const

Gets the standard BLE properties of the characteristic.

Returns

The properties of the characteristic. See CharacteristicProperties for the different values (it may be a combination of them).

readValueAsync()

std::future< std::vector< std::uint8_t > > Systemic::BluetoothLE::Characteristic::readValueAsync

(

)

Reads the value from the characteristic.

The call fails if the characteristic is not readable.

Returns

A future with the read value as a vector of bytes.

subscribeAsync()

std::future< BleRequestStatus > Systemic::BluetoothLE::Characteristic::subscribeAsync

(

const std::function< void(const std::vector< std::uint8_t > &)> &

onValueChanged

)

Subscribes for value changes of the characteristic.

Replaces a previously registered value change callback. The call fails if the characteristic doesn't support notifications.

Parameters

onValueChanged

Called when the value of the characteristic changes.

Returns

A future with the resulting request status.

unsubscribeAsync()

std::future< BleRequestStatus > Systemic::BluetoothLE::Characteristic::unsubscribeAsync

(

)

Unsubscribes from value changes of the characteristic.

Returns

A future with the resulting request status.

uuid()

winrt::guid Systemic::BluetoothLE::Characteristic::uuid

(

)

const

Gets the UUID of the characteristic.

Returns

The UUID of the characteristic.

writeAsync()

std::future< BleRequestStatus > Systemic::BluetoothLE::Characteristic::writeAsync	(	const std::vector< std::uint8_t > &	data,
		bool	withoutResponse = false
	)

Writes the given data to the value of the characteristic.

The call fails if the characteristic is not writable.

Parameters

data	The data to write to the characteristic (may be empty).
withoutResponse	Whether to wait for the peripheral to respond.

Returns

A future with the resulting request status.

---

The documentation for this class was generated from the following file:

• WinRTBle/src/LibWinRTBle/Systemic/BluetoothLE/Characteristic.h