net.hadess.SensorProxy.Compass
net.hadess.SensorProxy.Compass — D-Bus proxy to access Compass sensors
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Description
After checking the availability of the sensor type you want to monitor,
call the net.hadess.SensorProxy.ClaimCompass() method to start updating
the properties from the hardware readings.
The object path will be "/net/hadess/SensorProxy/Compass".
Method Details
The ClaimCompass() method
ClaimCompass ();
To start receiving compass heading updates from the proxy, the
application must call the net.hadess.SensorProxy.ClaimCompass() method. It can do so
whether a compass is available or not, updates would then be sent
when such a sensor appears.
Applications should call net.hadess.SensorProxy.ReleaseCompass() when readings are
not required anymore. This prevents the sensor proxy from polling the device, thus
increasing wake-ups and reducing battery life.
Note that Compass information is only available to Geoclue by default, which will
proxy the magnetic heading information, and transform it to True North heading.
The ReleaseCompass() method
ReleaseCompass ();
This should be called as soon as readings are not required anymore. Note
that resources are freed up if a monitoring application exits without
calling net.hadess.SensorProxy.ReleaseCompass(), crashes or the sensor disappears.
Property Details
The "HasCompass" property
HasCompass readable b
Whether a supported compass is present on the system.
The "CompassHeading" property
CompassHeading readable d
The compass heading in degrees with respect to magnetic North direction, in
clockwise order. That means North becomes 0 degree, East: 90 degrees,
South: 180 degrees, West: 270 degrees and so on. When unknown,
it's set to -1.0.