Windows UWP Sensor API Reference

Devices/Sensors API

This section provides reference documentation for the Windows Universal Platform (UWP) APIs related to device sensors. UWP apps can leverage a wide range of device sensors to gather environmental data, track user motion, and enhance user experiences.

Core Concepts

UWP sensor APIs are designed to provide a consistent and simplified interface for accessing hardware sensors. Key concepts include:

• Sensor Types: A variety of sensor types are supported, such as accelerometers, gyroscopes, magnetometers, barometers, light sensors, and more.
• Data Access: Apps can read sensor data asynchronously, typically receiving readings at a specified report interval.
• Permissions: Access to certain sensors requires user consent, managed through app manifest declarations.
• Sensor States: APIs allow checking sensor availability, reading capabilities, and managing sensor power states.

Key Classes and Interfaces

The primary namespace for sensor interactions is Windows.Devices.Sensors. Here are some of the most commonly used classes:

Getting Started with Sensors

Here's a simplified example of how to access accelerometer data:

using Windows.Devices.Sensors;
using System;

public sealed partial class MainPage : Page
{
    private Accelerometer _accelerometer;
    private uint _desiredReportInterval;

    public MainPage()
    {
        this.InitializeComponent();
        InitializeSensor();
    }

    private void InitializeSensor()
    {
        _accelerometer = Accelerometer.GetDefault();

        if (_accelerometer != null)
        {
            // Set the desired report interval to the fastest supported by the sensor
            _desiredReportInterval = _accelerometer.MinimumReportInterval;
            _accelerometer.ReportInterval = _desiredReportInterval;

            // Subscribe to the ReadingChanged event
            _accelerometer.ReadingChanged += Accelerometer_ReadingChanged;

            // Enable sensor reporting
            _accelerometer.ReportLatency = 0; // Get readings as soon as they are available
        }
        else
        {
            // Handle case where no accelerometer is found
            System.Diagnostics.Debug.WriteLine("No accelerometer found.");
        }
    }

    private void Accelerometer_ReadingChanged(Accelerometer sender, AccelerometerReadingChangedEventArgs args)
    {
        // Get the latest reading
        AccelerometerReading reading = args.Reading;

        // Update UI on the UI thread
        var dispatcher = CoreWindow.GetForCurrentThread().Dispatcher;
        if (dispatcher.HasThreadAccess)
        {
            UpdateSensorReadings(reading);
        }
        else
        {
            dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => UpdateSensorReadings(reading));
        }
    }

    private void UpdateSensorReadings(AccelerometerReading reading)
    {
        // Display X, Y, and Z values
        XValueTextBlock.Text = $"X: {reading.AccelerationX:F2}";
        YValueTextBlock.Text = $"Y: {reading.AccelerationY:F2}";
        ZValueTextBlock.Text = $"Z: {reading.AccelerationZ:F2}";
    }

    // Remember to unsubscribe from events and potentially disable sensors when the page is unloaded
    protected override void OnNavigatedFrom(NavigationEventArgs e)
    {
        if (_accelerometer != null)
        {
            _accelerometer.ReadingChanged -= Accelerometer_ReadingChanged;
        }
        base.OnNavigatedFrom(e);
    }
}
            

Additional Resources

• Design Guidelines for Sensors
• Getting Sensor Data (UWP)
• Accelerometer Sample