Android Kotlin, Use multiple sensors simultaniously

Question

I want to use my phone's accelerometer and gyroscope and store the data in a file (finally csv). Currently I am using the following code in onSensorChanged Function

override fun onSensorChanged(event: SensorEvent?) {
        if (event != null) {
            val timeInMills = System.currentTimeMillis() + (event.timestamp - SystemClock.elapsedRealtimeNanos()) / 1000000
            binding.tvShowDataTime.text = (timeInMills / 1000).toString()

            var accData = ""
            var gyroData = ""
            if (event.sensor.type == Sensor.TYPE_ACCELEROMETER) {
                accData += "${event!!.values[0]}," +
                        "${event!!.values[1]}," +
                        "${event!!.values[2]},"
            }

            if (event.sensor.type == Sensor.TYPE_GYROSCOPE) {
                gyroData += "${event!!.values[0]}," +
                        "${event!!.values[1]}," +
                        "${event!!.values[2]},"
            }

            val data = accData + gyroData + "\n"
            Log.d("DataSensor", data)
            writer.appendText(data)
        }

the output that I am getting in the file is as following

-0.01585245,-0.09661021,9.810872,
-9.162709E-4,1.5271181E-4,0.0015271181,
-0.012562319,-0.09421739,9.824033,
-0.0010689828,-6.1084726E-4,0.0012216945,

it is comming alternatingly on new lines

e.g.

accelerometer(x,y,z,)
gyroscope(x,y,z,)
accelerometer(x,y,z,)
gyroscope(x,y,z,) ......

but I want accelerometer and gyroscope on same line ax,ay,az,gx,gy,gz

how can I do it?

Answer 1

My suggestion is to bring in some architecture into this.
Try to separate your onSensorChanged method from the "write-file" method. You should then be able to see how to write the "combination"-function.

Suggestion for your "combination"-function:
Let your onSensorChanged-Method return/set you the a specific value. I would assume that your values are calling cyclic (and in same order) your onSensorChanged-Method? So it would be easy to just await if both values (modulo counter or boolean-flag if only 2 sensors) got updated and then fire your write-function based on this condition.