get tilt angle Android

Question

I'm trying to get the tilt angle, roll angle from my sensors from my android phone but with no success so far,

when I click on my button which should give me the 3 angles, I get "results: 0.0 -0.0 -0.0"

package com.example;

import android.app.Activity;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Button;
import android.view.View;


public class MyActivity extends Activity
{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        final float[] mValuesMagnet      = new float[3];
        final float[] mValuesAccel       = new float[3];
        final float[] mValuesOrientation = new float[3];
        final float[] mRotationMatrix    = new float[9];

        final Button btn_valider = (Button) findViewById(R.id.btn1);
        final TextView txt1 = (TextView) findViewById(R.id.textView1);
        final SensorEventListener mEventListener = new SensorEventListener() {
            public void onAccuracyChanged(Sensor sensor, int accuracy) {
            }

            public void onSensorChanged(SensorEvent event) {
                // Handle the events for which we registered
                switch (event.sensor.getType()) {
                    case Sensor.TYPE_ACCELEROMETER:
                        System.arraycopy(event.values, 0, mValuesAccel, 0, 3);
                        break;

                    case Sensor.TYPE_MAGNETIC_FIELD:
                        System.arraycopy(event.values, 0, mValuesMagnet, 0, 3);
                        break;
                }
            };
        };
        btn_valider.setOnClickListener(new View.OnClickListener()
        {
            public void onClick(View view)
            {
                SensorManager.getRotationMatrix(mRotationMatrix, null, mValuesAccel, mValuesMagnet);
                SensorManager.getOrientation(mRotationMatrix, mValuesOrientation);
                final CharSequence test;
                test = "results: " + mValuesOrientation[0] +" "+mValuesOrientation[1]+ " "+ mValuesOrientation[2];
                txt1.setText(test);
            }
        });

    }
}

Answer 1

Your almost there with the code Mike, but to enable the data to be retrieved by the event listener for any of the sensors, the event listener and sensor wanted must be registered with the SensorManager class using:

SensorManager _sensorManager;

_sensorManager.registerListener(mEventListener, _sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), 
                SensorManager.SENSOR_DELAY_NORMAL);

Below is your code adapted to show the data that I believe is what you want to see.

import android.app.Activity;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Button;
import android.view.View;


public class StackOverflowTestingGroundActivity extends Activity
{   
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);        

        SensorManager sensorManager = (SensorManager) this.getSystemService(SENSOR_SERVICE);        

        final float[] mValuesMagnet      = new float[3];
        final float[] mValuesAccel       = new float[3];
        final float[] mValuesOrientation = new float[3];
        final float[] mRotationMatrix    = new float[9];

        final Button btn_valider = (Button) findViewById(R.id.btn1);
        final TextView txt1 = (TextView) findViewById(R.id.textView1);
        final SensorEventListener mEventListener = new SensorEventListener() {
            public void onAccuracyChanged(Sensor sensor, int accuracy) {
            }

            public void onSensorChanged(SensorEvent event) {
                // Handle the events for which we registered
                switch (event.sensor.getType()) {
                    case Sensor.TYPE_ACCELEROMETER:
                        System.arraycopy(event.values, 0, mValuesAccel, 0, 3);
                        break;

                    case Sensor.TYPE_MAGNETIC_FIELD:
                        System.arraycopy(event.values, 0, mValuesMagnet, 0, 3);
                        break;
                }
            };
        };

        // You have set the event lisetner up, now just need to register this with the
        // sensor manager along with the sensor wanted.
        setListners(sensorManager, mEventListener);

        btn_valider.setOnClickListener(new View.OnClickListener()
        {
            public void onClick(View view)
            {
                SensorManager.getRotationMatrix(mRotationMatrix, null, mValuesAccel, mValuesMagnet);
                SensorManager.getOrientation(mRotationMatrix, mValuesOrientation);
                final CharSequence test;
                test = "results: " + mValuesOrientation[0] +" "+mValuesOrientation[1]+ " "+ mValuesOrientation[2];
                txt1.setText(test);
            }
        });

    }

    // Register the event listener and sensor type.
    public void setListners(SensorManager sensorManager, SensorEventListener mEventListener)
    {
        sensorManager.registerListener(mEventListener, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), 
                SensorManager.SENSOR_DELAY_NORMAL);
        sensorManager.registerListener(mEventListener, sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD), 
                SensorManager.SENSOR_DELAY_NORMAL);
    }
}