ValueChanged没有用C＃Win10点燃 [英] ValueChanged not firing with C# Win10 Iot

问题描述

看起来像 Win10 IoT - RaspBerry Pi2 ：当GPIO发生变化时，ValueChanged不被调用$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ p> public sealed class StartupTask：IBackgroundTask
{
private const int SENSOR_PIN = 17;
私人GpioPin pinSensor;

public void Run（IBackgroundTaskInstance taskInstance）
{
taskInstance.Canceled + = TaskInstance_Canceled; //destructor

var gpio = GpioController.GetDefault（）;

if（gpio！= null）
{
pinSensor = gpio.OpenPin（SENSOR_PIN）; //也尝试过GpioSharingMode.SharedReadOnly

var r = pinSensor.Read（）; //如果传感器发生变化，就进行更改用quickwatch验证

pinSensor.SetDriveMode（GpioPinDriveMode.Input）;
pinSensor.DebounceTimeout = TimeSpan.FromMilliseconds（20）;

pinSensor.ValueChanged + = PinIn_ValueChanged;
}
}

private void PinIn_ValueChanged（GpioPin sender，GpioPinValueChangedEventArgs args）
{
//从未得到...
}

private void TaskInstance_Canceled（IBackgroundTaskInstance sender，BackgroundTaskCancellationReason reason）
{
pinSensor.Dispose（）;
}
}


带领传感器和快速表示GpioPinValue在高和低...所以应该得到打击...

当我将其设置为输入后检索驱动器模式。它告诉我它实际上被设置为输入：

  var dm = pinSensor.GetDriveMode（）; 
  

如链接堆栈溢出问题的注释中所建议的那样。那我做错了什么？更重要的是：为什么？

解决方案

当Run方法结束时，除非创建延期对象，
背景应用程序结束。异步
编程的常见做法是采取如下推迟：

  var deferval = taskInstance.GetDeferral（）; 
  

参考：开发背景应用程序

It seems exactly like Win10 IoT - RaspBerry Pi2: ValueChanged not called when GPIO change I have a raspberry pi 2 with win10 IoT (creator version) and have this C# code:

public sealed class StartupTask : IBackgroundTask
{
    private const int SENSOR_PIN = 17;
    private GpioPin pinSensor;

    public void Run(IBackgroundTaskInstance taskInstance)
    {
        taskInstance.Canceled += TaskInstance_Canceled; // "destructor"

        var gpio = GpioController.GetDefault();

        if (gpio != null)
        {
            pinSensor = gpio.OpenPin(SENSOR_PIN); // also tried with GpioSharingMode.SharedReadOnly

            var r = pinSensor.Read(); // works and changes if sensor changes. Verified with quickwatch

            pinSensor.SetDriveMode(GpioPinDriveMode.Input);
            pinSensor.DebounceTimeout = TimeSpan.FromMilliseconds(20);

            pinSensor.ValueChanged += PinIn_ValueChanged;
        }
    }

    private void PinIn_ValueChanged(GpioPin sender, GpioPinValueChangedEventArgs args)
    {
        // never gets hit... 
    }

    private void TaskInstance_Canceled(IBackgroundTaskInstance sender, BackgroundTaskCancellationReason reason)
    {
        pinSensor.Dispose();
    }
}

led on sensor and quickwatch say the GpioPinValue does alternate between high and low... so should get hit...

When I retrieve the drive mode after setting it to input. It tells me it actually is set to input:

var dm = pinSensor.GetDriveMode();

as was suggested in the comment of the linked stack overflow issue. So what am I doing wrong? And more important: why?

解决方案

When the Run method ends, unless a deferral object is created, the Background Application ends. The common practice, for asynchronous programming is to take a deferral like this:

var deferval = taskInstance.GetDeferral();

Ref:Developing Background Applications

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