Using the Accelerometer Class

Accelerometer, like the other sensor types, uses an event-based model for monitoring changes to sensor readings.

The event to use is the base class SensorBase event: CurrentValueChanged. Subscribing to the event can be done as follows:

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var accelerometer = new Accelerometer();
accelerometer.CurrentValueChanged += HandleSensorValueChanged;
accelerometer.Start();

When the CurrentValueChanged event is raised, the event handler receives a SensorReadingEventArgs<AccelerometerReading> object, as shown:

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void HandleSensorValueChanged(
    object sender, SensorReadingEventArgs<AccelerometerReading> e)
{
    ProcessReading(e.SensorReading);
}

SensorReadingEventArgs provides a reference to the Accelerometer via its single Sensor property. AccelerometerReading contains an Acceleration property, which is a Microsoft.Xna.Framework.Vector3. XAML apps do not have a type representing a three-dimensional vector baked into the SDK; thus, there is some crossover here, and Vector3 is used throughout the phone sensor API.

Rather than relying on the XNA Vector3 type in the sample code, a custom ThreeDimensionalVector class is used that has a markedly simpler implementation and uses properties rather than fields to access vector dimension values, which improves its compatibility with the XAMLdata binding infrastructure.