Retrieving heart rate data from Android watch face service

Question

Does anyone have links to sample code that shows how to set up heart sensor data retrieval directly from CanvasWatchFaceService or CanvasWatchFaceService.Engine ?

(Most of the code I've seen thus far perform sensor data retrieval from a wearable's Activity class, but not from a watch face environment.)

I've tried setting things up this way:

private class Engine extends CanvasWatchFaceService.Engine implements SensorEventListener {
    ...
    ... // implement interface methods
}

But I keep getting a null object for my sensor.

My manifest contains:

<uses-feature android:name="android.hardware.type.watch" />
<uses-permission android:name="android.permission.BODY_SENSORS" />

Answer 1

Check if you requested android.permission.BODY_SENSORS permission in your both mobile and wearable AndroidManifest.

Also, look into the logcat of your wearable device and grep for android.permission.BODY_SENSORS.