Question

在发布问题之前，我做了10天的研究，所以真的希望有人可以解决这个问题。

问题是任何可绑定控件一旦更改了singleton类的绑定列表就不会更新。这是多线程应用程序的常见问题。大多数（如果不是全部）解决方案提供了从父线程初始化bindlinglist或集合的建议，然后进行了一些调用。不是我想要的。如果使用静态类而不是单例，则同样的问题仍然存在。

基本上，应用程序会触发一些任务，这些任务又会在不同的业务类上创建对象。这些对象将消息发布到绑定列表中，该列表应更新UI列表框，但不会。是的，消息对象在列表中，并且在之后绑定 TASK完成工作（显示的项目）。锁定/解锁对象访问也不是问题。

感谢任何建议/解决方案

业务对象的精简版本：

namespace MyNameSpace { public class Message { private string messageSummary; public Message() { } public string MessageSummary { set { messageSummary = value; } get { return messageSummary; } } } }

执行某些操作的另一个类的精简版：

namespace MyNameSpace { public class WorkDoingClass { public WorkDoingClass() { } public void DoSomeWork() { //some routines Message messageObj = new Message(); messageObj.MessageSummary = "DoSOmrWork Finished"; } public void DoSomeOtherWork() { //some routines Message messageObj = new Message(); messageObj.MessageSummary = "DoSomeOtherWork Finished"; AllMessages.Instance.AllMessagesBindingList.Add(messageObj); } } }

的Singleton：

namespace MyNameSpace { public sealed class AllMessages { private static readonly AllMessages _instance = new AllMessages(); private BindingList<Message> _allMessagesBL; public WorkDoingClass() { _allMessagesBL = new BindingList<Message>(); } public static AllMessages Instance { get { return _instance; } } public BindingList<Message> AllMessagesBindingList { get { return _allMessagesBL}; } } }

这也是调用开始时的修剪版本：

namespace MyNameSpace { public partial class Form1 : Form { private Task _TaskSqlData; private CancellationTokenSource cTokenSourceSql; public Form1() { InitializeComponent(); listBox1.DataSource = AllMessages.Instance.AllMessagesBindingList; listBox1.DisplayMember = "MessageSummary"; } private void button1_Click(object sender, EventArgs e) { cTokenSourceSql = new CancellationTokenSource(); var tokenSqlData = cTokenSourceSql.Token; if (this._TaskSqlData != null) { if (this._TaskSqlData.Status == TaskStatus.Running) this.cTokenSourceSql.Cancel(); this._TaskSqlData.Dispose(); this._TaskSqlData = null; } _TaskSqlData = Task.Factory.StartNew(() => StartDoingWork(this, tokenSqlData, null), tokenSqlData); } public void StartDoingWork(object sender, CancellationToken ct, EventArgs e) { if (ct.IsCancellationRequested) ct.ThrowIfCancellationRequested(); WorkDoingClass work = new WorkDoingClass(); work.DoSomeOtherWork(); }

Answer 1

您的问题是制作列表框的线程（主UI线程）与修改集合的线程（工作线程）不同。

尝试以下代码。它可以解决您的问题。我使用SynchronizationContext来同步两个线程，这两个线程与Control.Invoke()具有相同的功能。

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        private Task _TaskSqlData;
        private CancellationTokenSource cTokenSourceSql;
        WorkDoingClass _work;

        public Form1()
        {
            InitializeComponent();
            listBox1.DataSource = AllMessages.Instance.AllMessagesBindingList;
            listBox1.DisplayMember = "MessageSummary";
            _work = new WorkDoingClass(SynchronizationContext.Current);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            cTokenSourceSql = new CancellationTokenSource();
            var tokenSqlData = cTokenSourceSql.Token;
            if (this._TaskSqlData != null)
            {
                if (this._TaskSqlData.Status == TaskStatus.Running)
                    this.cTokenSourceSql.Cancel();
                this._TaskSqlData.Dispose();
                this._TaskSqlData = null;
            }
            _TaskSqlData = Task.Factory.StartNew(()
                            => StartDoingWork(this, tokenSqlData, null), tokenSqlData);
        }

        public void StartDoingWork(object sender, CancellationToken ct, EventArgs e)
        {
            if (ct.IsCancellationRequested)
                ct.ThrowIfCancellationRequested();

            _work.DoSomeOtherWork();
        }
    }

    public class Message
    {
        private string messageSummary;
        public Message() { }
        public string MessageSummary
        {
            set { messageSummary = value; }
            get { return messageSummary; }
        }
    }

    public class WorkDoingClass
    {
        private SynchronizationContext _syncContext;

        public WorkDoingClass() { }

        public WorkDoingClass(SynchronizationContext _syncContext)
        {
            // TODO: Complete member initialization
            this._syncContext = _syncContext;
        }
        public void DoSomeWork()
        {
            //some routines
            Message messageObj = new Message();
            messageObj.MessageSummary = "DoSOmrWork Finished";
        }

        public void DoSomeOtherWork()
        {
            _syncContext.Send(DoWork, null);
        }

        private static void DoWork(object arg)
        {
            //some routines
            Message messageObj = new Message();
            messageObj.MessageSummary = "DoSomeOtherWork Finished";
            AllMessages.Instance.AllMessagesBindingList.Add(messageObj);
        }
    }

    public sealed class AllMessages
    {
        private static readonly AllMessages _instance = new AllMessages();
        private BindingList<Message> _allMessagesBL;

        public AllMessages() { _allMessagesBL = new BindingList<Message>(); }

        public static AllMessages Instance
        {
            get { return _instance; }
        }

        public BindingList<Message> AllMessagesBindingList
        {
            get { return _allMessagesBL; }
        }
    }
}

任务/多线程时的Singleton可绑定控件

1 个答案: