Performance & motion

PERF_VEHICLE_SPEED

What it is

Speed of the vehicle

The value must be positive when the vehicle is moving forward and negative when the vehicle is moving backward. This value is independent of gear value (CURRENT_GEAR or GEAR_SELECTION), for example, if GEAR_SELECTION is GEAR_NEUTRAL, PERF_VEHICLE_SPEED is positive when the vehicle is moving forward, negative when moving backward, and zero when not moving.

How the ID is built

A property ID is a 32-bit value packing four fields. Reading 0x11600207 apart:

Field	Mask	Value	Means
Group	0xf0000000	0x10000000	SYSTEM
Area	0x0f000000	0x01000000	GLOBAL
Type	0x00ff0000	0x00600000	FLOAT
Ordinal	0x0000ffff	0x00000207	0x207

Reading it from an app

CarPropertyManager mgr = (CarPropertyManager)
        car.getCarManager(Car.PROPERTY_SERVICE);

mgr.registerCallback(callback,
        VehiclePropertyIds.PERF_VEHICLE_SPEED,
        CarPropertyManager.SENSOR_RATE_ONCHANGE);

This property is read-only — writes are rejected. It changes continuously, so subscribe at a sample rate rather than polling.