c# - UWP 上的 Accelerometer.Shaken 事件不起作用，有什么解决方案吗？

Question

我试图对 Accelerometer.Shaken 事件实现某种处理程序，然后我发现 Windows 10 尚不支持此事件，从 answer here 可以看出。

现在，即使 shaken 事件不起作用，Accelerometer.ReadingChanged 事件也能正常工作。所以我在想，是否可以从该数据中手动检测摇晃手势？我的意思是，这可能是可能的，但我真的不知道从哪里开始，有人知道吗？

您每 x 毫秒获得一次 X、Y 和 Z 坐标，一定有某种方法可以根据该数据计算摇动手势。

感谢您的帮助!

Answer 1

没关系，我最终编写了自己的类来解决问题，我会把它留在这里以防它对其他人有用:

/// <summary>
/// A static class that manages the Shaken event for the Accelerometer class
/// </summary>
public static class CustomAccelerometer
{
    // The minimum acceleration value to trigger the Shaken event
    private const double AccelerationThreshold = 2;

    // The minimum interval in milliseconds between two consecutive calls for the Shaken event
    private const int ShakenInterval = 500;

    private static bool _AccelerometerLoaded;

    private static Accelerometer _DefaultAccelerometer;

    /// <summary>
    /// Gets the current Accelerometer in use
    /// </summary>
    private static Accelerometer DefaultAccelerometer
    {
        get
        {
            if (!_AccelerometerLoaded)
            {
                _AccelerometerLoaded = true;
                _DefaultAccelerometer = Accelerometer.GetDefault();
            }
            return _DefaultAccelerometer;
        }
    }

    private static DateTime _ShakenTimespan = DateTime.Now;

    private static bool _Enabled;

    /// <summary>
    /// Gets or sets whether or not the Accelerometer is currently enabled and can raise the Shaken event
    /// </summary>
    public static bool Enabled
    {
        get { return _Enabled; }
        set
        {
            if (_Enabled != value && DefaultAccelerometer != null)
            {
                if (value) DefaultAccelerometer.ReadingChanged += _DefaultAccelerometer_ReadingChanged;
                else DefaultAccelerometer.ReadingChanged -= _DefaultAccelerometer_ReadingChanged;
            }
            _Enabled = value;
        }
    }

    // Handles the ReadingChanged event and raises the Shaken event when necessary
    private static void _DefaultAccelerometer_ReadingChanged(Accelerometer sender, AccelerometerReadingChangedEventArgs args)
    {
        double g = Math.Round(args.Reading.AccelerationX.Square() + args.Reading.AccelerationY.Square() + args.Reading.AccelerationZ.Square());
        if (g > AccelerationThreshold && DateTime.Now.Subtract(_ShakenTimespan).Milliseconds > ShakenInterval)
        {
            _ShakenTimespan = DateTime.Now;
            Shaken?.Invoke(null, EventArgs.Empty);
        }
    }

    /// <summary>
    /// Raised whenever the Accelerometer detects a shaking gesture
    /// </summary>
    public static event EventHandler Shaken;
}

要使用它，只需启用它并订阅它的事件:

CustomAccelerometer.Enabled = true;
CustomAccelerometer.Shaken += (s, e) =>
{
    Debug.WriteLine("The device was shaken!");
};

编辑:忘记添加Square方法代码，这里是:

/// <summary>
/// Returns the square of the given double value
/// </summary>
/// <param name="value">The input value</param>
public static double Square(this double value) => value * value;