The accelerometer data can be accessed via the AccelerometerReadingEventArgs class. The class has values for the X, Y, and Z axis. The values are of type double and between -2 and 2 which related to acceleration “for each axis in gravitational units” – 1 is the gravitational force of the earth. See: http://msdn.microsoft.com/en-us/library/ff431744(v=vs.92).aspx and http://msdn.microsoft.com/en-us/library/ff431810(v=vs.92).aspx or on page 80ff, C. Petzold, Programming Windows Phone 7.
A typical exercise for understanding the accelerometer is to create a bubble level (a tool to measure if something is horizontal or vertical – e.g. for hanging pictures on the wall). You probably want to freshen up on arctan2 – at least I needed
See below the c# example reading out the accelerometer on a windows phone 7. You can also download the accelerometer project directory in a single ZIP-file.
using System;
using System.Windows;
using Microsoft.Phone.Controls;
using Microsoft.Devices.Sensors;
// A simple example to read the accelerometer and display the values
// In order to make it work you have to add the refercerence to
// Microsoft.Devices.Sensors to your project. To do this right-click
// in the Solution Explorer on References and than choose add Reference
// in the dialog then select Microsoft.Devices.Sensors
// Albrecht Schmidt, University of Stuttgart
// for a more comprehensive example see:
// http://msdn.microsoft.com/en-us/library/ff431810(v=vs.92).aspx
// http://msdn.microsoft.com/en-us/library/ff431744(v=vs.92).aspx
// and page 80ff, C. Petzold, Programming Windows Phone 7
namespace Accl_X_Y_Z
{
public partial class MainPage : PhoneApplicationPage
{
Accelerometer accelerometer;
public MainPage()
{
InitializeComponent();
// create a new instance
accelerometer = new Accelerometer();
// register a callback function for when values change
accelerometer.ReadingChanged += new EventHandler<AccelerometerReadingEventArgs>(accelerometer_ReadingChanged);
// start the accelerometer
accelerometer.Start();
}
void accelerometer_ReadingChanged(object sender, AccelerometerReadingEventArgs e)
{
// required as from here the textBlocks cannot be accessed
Deployment.Current.Dispatcher.BeginInvoke(() => ChangeUI(e));
}
void ChangeUI(AccelerometerReadingEventArgs e)
{
// show the values on the screen
textBlock1.Text = "X: " + e.X.ToString("0.000");
textBlock2.Text = "Y: " + e.Y.ToString("0.000");
textBlock3.Text = "Z: " + e.Z.ToString("0.000");
}
}
}
