bob wrote:
> Here is the *correct* (until proven otherwise) version of a compass for a
> device lying flat on a table:
>
>
As long as you have the device lying flat, i.e., with no roll, then the
Meier version is fine, if computationally
expensive per the documentation.
> package com.magnet_test;
>
> Do you own the domain "magnet_test.com"?
You should (roughly) conform to the Java Coding Conventions.
import android.hardware.Sensor;
> import android.hardware.SensorEvent;
> import android.hardware.SensorEventListener;
>
> public class Magnet_Listener implements SensorEventListener {
>
The Java Coding Conventions call for underscores only in constant variable
names.
Otherwise, use camel case.
>
> private float[] magneticFieldValues;
>
> @Override
> public void onAccuracyChanged(Sensor sensor, int accuracy) {
>
> }
>
> @Override
> public void onSensorChanged(SensorEvent sensorEvent) {
> if (sensorEvent.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD)
> magneticFieldValues = sensorEvent.values;
> float x = magneticFieldValues[0];
> float y = magneticFieldValues[1];
> float angle = (float) Math.atan2(y, x);
> float angle_in_degrees = (float) Math.toDegrees(angle) + 180;
> System.out.println("angle = " + angle_in_degrees);
>
> }
> }
>
>
> *Inspired by code from Reto Meier.*
>
>
> On Thursday, September 27, 2012 10:33:31 AM UTC-5, bob wrote:
>>
>> So, I'm trying to learn how to make an android compass.
>>
>> Naturally, I used a site called google and typed the following in:
>>
>> "making an android compass"
>>
>> I found myself at this URL:
>>
>>
>> http://android-er.blogspot.com/2010/08/simple-compass-sensormanager-and.html
>>
>> After looking thru it, I'm thinking it's incorrect.
>>
>> There is this suspiciously simple method:
>>
>> public void onSensorChanged(SensorEvent event) {
>> // TODO Auto-generated method stub
>> myCompassView.updateDirection((float)event.values[0]);
>> }
>>
>>
>>
>> Basically, it seems like they are using the x component of the force
>> vector as if it were an angle. Can someone else look at this and let me
>> know what you think?
>>
>>
--
You received this message because you are subscribed to the Google
Groups "Android Developers" group.
To post to this group, send email to android-developers@googlegroups.com
To unsubscribe from this group, send email to
android-developers+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/android-developers?hl=en
