在Myo集线器初始化过程中未触发调度程序

Question

我正在将Myo臂章的初始化代码移植到WPF应用程序，该应用程序使用C#包装器http://goo.gl/HfwqQe与设备交互。

但是，当我在用户控件后面的代码中添加InitializeComponent();下的初始化代码时，永远不会触发更新具有连接状态的文本框的行，this.Dispatcher.Invoke((Action)(() =>。

我在dispatcher代码之前在行上设置一个断点来调试它，它被称为hub.MyoConnected += (sender, e) =>，这意味着Myo已经连接，但是在更新之后的dispatcher行永远不会调用和跳过statusTbx。

有人知道这是什么导致的吗？

我不知道为什么它不会将连接状态输出到textbox。这段代码以前同样有效，但这是我正在使用的C#包装器的一个新版本。

控制台示例运行良好，http://goo.gl/RFHLym和输出连接到控制台，但我无法让它输出到textbox的连接。

这是获取Myo arm波段连接状态的完整代码：

using MyoSharp.Communication;
using MyoSharp.Device;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace MyoTestv4
{
    /// <summary>
    /// Interaction logic for ProductsView.xaml
    /// </summary>
    public partial class AdductionAbductionFlexionView : UserControl
    {
        public AdductionAbductionFlexionView()
        {
            InitializeComponent();



            // create a hub that will manage Myo devices for us
            using (var channel = Channel.Create(ChannelDriver.Create(ChannelBridge.Create())))
            using (var hub = Hub.Create(channel))
            {
                 //set a bpoint here, gets triggered
                // listen for when the Myo connects
                hub.MyoConnected += (sender, e) =>
                {
                     //set a bpoint here, doesn't get triggered
                    this.Dispatcher.Invoke((Action)(() =>
                    {
                        statusTbx.Text = "Myo has connected! " + e.Myo.Handle;
                        //Console.WriteLine("Myo {0} has connected!", e.Myo.Handle);
                        e.Myo.Vibrate(VibrationType.Short);

                    }));
                };

                // listen for when the Myo disconnects
                hub.MyoDisconnected += (sender, e) =>
                {
                    this.Dispatcher.Invoke((Action)(() =>
                    {
                        statusTbx.Text = "Myo has disconnected!";
                        //Console.WriteLine("Oh no! It looks like {0} arm Myo has disconnected!", e.Myo.Arm);
                        e.Myo.Vibrate(VibrationType.Medium);
                    }));
                };

                // start listening for Myo data
                channel.StartListening();
            }
        }
    }
}

Answer 1

您将得到此错误，因为channel和hub在调用后立即被释放。

channel.StartListening();

using是一种方便的方式来为您释放对象，在这种情况下，这是不需要的。请参考使用语句(C#引用)获得更多信息。

尝试以下步骤来解决问题。1.将通道和集线器声明为类的私有字段。2.不要使用using关键字。3.当hub和channel被释放时，记住要处理AdductionAbductionFlexionView和AdductionAbductionFlexionView。

public partial class AdductionAbductionFlexionView : UserControl
{
    IChannel channel;
    IHub hub;

    public AdductionAbductionFlexionView()
    {
        InitializeComponent();

        // create a hub that will manage Myo devices for us
        channel = Channel.Create(ChannelDriver.Create(ChannelBridge.Create()));
        hub = Hub.Create(channel);

        //set a bpoint here, gets triggered
        // listen for when the Myo connects
        hub.MyoConnected += (sender, e) =>
        {
            //set a bpoint here, doesn't get triggered
            this.Dispatcher.Invoke((Action)(() =>
            {
                statusTbx.Text = "Myo has connected! " + e.Myo.Handle;
                //Console.WriteLine("Myo {0} has connected!", e.Myo.Handle);
                e.Myo.Vibrate(VibrationType.Short);

            }));
        };

        // listen for when the Myo disconnects
        hub.MyoDisconnected += (sender, e) =>
        {
            this.Dispatcher.Invoke((Action)(() =>
            {
                statusTbx.Text = "Myo has disconnected!";
                //Console.WriteLine("Oh no! It looks like {0} arm Myo has disconnected!", e.Myo.Arm);
                e.Myo.Vibrate(VibrationType.Medium);
            }));
        };

        // start listening for Myo data
        channel.StartListening();
    }
}