Accessing +data from the physical sensors of a device

The Sensor Service +API allows widgets to access data provided by the +physical sensors of a device. The data from a given sensor is mapped to one +or more sensor channels, which the API can listen to. The available sensors +depend on the device. You can use the Sensor Service to create widgets that:

Search for sensor channels available on a device
Listen for data provided by one or more sensor channels
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Retrieve information about sensor channel properties
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Sensor information involves the following concepts:

Sensor is a physical sensor on a device (a piece of +hardware combined with a software plugin). A single sensor can provide multiple +sensor channels, such as a raw data channel and event channels, or incorporate +multiple sensor readings into a single sensor channel.
Sensor property is a configuration value of a sensor. +The property affects all sensor channels that draw data from the sensor.
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Channel is an abstraction of a physical sensor. Data +from one physical sensor can be mapped to multiple sensor channels.
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Channel property is a configuration value of a sensor +channel. The property affects all clients listening to the channel.
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Accessing the API and supported methods

To create a service +object for the Sensor Service API, use Service.Sensor to +identify the service provider and ISensor to identify +the supported interface:

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var so = device.getServiceObject("Service.Sensor", "ISensor");

The ISensor interface provides the following methods:

FindSensorChannel()
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Use the FindSensorChannel() method to search for +sensor channels available on the device.
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RegisterForNotification()
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Use the RegisterForNotification() method to receive +data from one sensor channel.
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Cancel()
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Use the Cancel() method to stop receiving data +provided by a RegisterForNotification() call.
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GetChannelProperty()
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Use the GetChannelProperty() method to retrieve +information about a sensor channel property.
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Using the service in a widget

To access sensor data on a device using the Sensor Service API:

Create a service +object for the API using device.getServiceObject().
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Define the +tasks you want to perform and choose the correct methods for them.
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Optionally, +define how you want the results filtered.
Define methods +to process the results.
Retrieve the +results using the methods from step 2. Use asynchronous methods together with callback().
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Process the +results using the methods defined in step 4.

For the complete source of a sample widget that demonstrates how to +use this service, see the +full example.