在 WinRT 上获取加速度计的设备 ID（或在后台监控加速度计）

Question

正在研究后台监控加速度计的方法

我们可以获得 Windows Phone 的示例，它在 MSDN 实现了它。

根据示例代码，需要加速度计的id。但是，没有属性获取 WinRT 的设备 ID。

var rs = await BackgroundExecutionManager.RequestAccessAsync();
if (rs != BackgroundAccessStatus.AllowedMayUseActiveRealTimeConnectivity
|| rs != BackgroundAccessStatus.AllowedWithAlwaysOnRealTimeConnectivity) return;

var btb = new BackgroundTaskBuilder() {
    Name = TaskName,
    TaskEntryPoint = TaskEntryPoint
};
btb.SetTrigger(trigger);
taskregist = btb.Register();
taskregist.Completed += new BackgroundTaskCompletedEventHandler(OnBackgroundTaskCompleted);

try {
    var dres = await trigger.RequestAsync();    // Requires the accelerometer's device-id
    switch (dres) {
    case DeviceTriggerResult.Allowed:
        break;
    case DeviceTriggerResult.LowBattery:
        break;
    case DeviceTriggerResult.DeniedBySystem:
        break;
    default:
        break;
    }
} catch (InvalidOperationException) {
}

我可以在 WinRT 设备的后台观察加速度计的状态吗？

Answer 1

基于 msdn，DeviceUseTrigger 后台任务只能从 Windows 运行时 phone 应用程序中访问传感器 API，其他 winrt 设备不能'支持

Sensors support in Windows Phone Store apps When running on a phone, a DeviceUseTrigger background task can access the sensors API only from within a Windows Runtime app. Using a DeviceUseTrigger background task to access the sensors API from within a Windows Phone Silverlight app is not supported.

这里是支持的列表

And 最后是一个通过处理 ReadingChanged 事件

使用加速度计数据的基本示例

public MainPage()
    {
        this.InitializeComponent();
        this.InitializeAccelerometer();
    }
    private Accelerometer _accelerometer;
    private void InitializeAccelerometer()
    {

        this._accelerometer = Accelerometer.GetDefault();
        if (_accelerometer == null)
        {
            AccelerometerTextBlock.Text = "No accelerometer found.";
            return;
        }

        uint minReportInterval = _accelerometer.MinimumReportInterval;
        var desiredReportInterval = minReportInterval > 16 ? minReportInterval : 16;
        this._accelerometer.ReportInterval = desiredReportInterval;
        this._accelerometer.ReadingChanged += Accelerometer_ReadingChanged;
    }
    private async void Accelerometer_ReadingChanged(Accelerometer sender, AccelerometerReadingChangedEventArgs args)
    {
        if (args.Reading != null)
        {
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                AccelerometerTextBlock.Text = String.Format(
                    "X: {0,5:0.00} - Y: {1,5:0.00} - Z: {2,5:0.00} - Timestamp: {3}",
                    args.Reading.AccelerationX,
                    args.Reading.AccelerationY,
                    args.Reading.AccelerationZ,
                    args.Reading.Timestamp);
            });
        }
    }

在 WinRT 上获取加速度计的设备 ID（或在后台监控加速度计）

Get an accelerometer's device id(or monitor an accelerometer in the backbround) on WinRT

c#

accelerometer

background-process

windows-8

windows-runtime