Question

我回电话说我是从固件中获取的。当我收到该回叫时，我想以适当的状态更新我的UI。所以我为每次回调都提出了属性更改事件，并且我在后台线程中订阅了该事件。

请在!WorkDone中查看（DoWork）时的相似内容。我阻止了调用，因为我希望后台线程保留在DoWork中直到更新完成（我应该使用ManualResetEvent？）。问题是即使我在WorkDone中将PropertyChanged设置为true它永远不会被设置，并且我更新UI的CurrentStatus永远不会更新并且程序进入无限循环。请帮忙。

private void StartCurrentRun(bool obj)
{
    this.worker = new BackgroundWorker();
    this.worker.WorkerReportsProgress = true;
    this.worker.WorkerSupportsCancellation = true;
    StartTimer();
    PropertyCallBackChangedInstance.PropertyChanged -= PropertyCallBackChangedInstance_PropertyChanged;
    WhenCancelledBlurVolumesGrid = false;
    OriginalTime = SelectedVolumeEstimatedTime();
    this.worker.DoWork += this.DoWork;
    this.worker.ProgressChanged += this.ProgressChanged;
    this.worker.RunWorkerCompleted += Worker_RunWorkerCompleted;
    IsLiveProgress = true;
    this.worker.RunWorkerAsync();
}

private void DoWork(object sender, DoWorkEventArgs e)
{
    try
    {
        CreateEventLogs.WriteToEventLog(string.Format("Run with Assay:{0} Volume{1} has been started", SelectedAssay, SelectedVolume), LogInformationType.Info);
        var instance = ConnectToInstrument.InstrumentConnectionInstance;
        instance.InitalizeRun(PopulateRespectiveVolumes());
        PropertyCallBackChangedInstance.PropertyChanged += PropertyCallBackChangedInstance_PropertyChanged;
        while (!WorkDone)
        {
            continue;
        }
    }
    catch (Exception ex)
    {
        CreateEventLogs.WriteToEventLog(string.Format("{0} - {1}", "Error occured during Run", ex.Message), LogInformationType.Error);
    }
}

private void PropertyCallBackChangedInstance_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
    //bool stepDone = false;
    if (e.PropertyName == "RunStepStatusName")
    {
        var value = sender as InstrumentCallBackProperties;
        Dispatcher.CurrentDispatcher.BeginInvoke((Action)(() => {
            CurrentStatus = value.RunStepStatusName;

            if (value.RunStepStatusName == "Step5")
            {
                WorkDone = true;
            }
        }));
        //stepDone = true;
    }
}

private void ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    this.ProgressValue = e.ProgressPercentage;
}

这是我调用它时的InitailizeRun方法我得到了回电

public async void InitalizeRun(VolumeInfo volumeInfo)
{
    AssayInfo AssayInfo = new AssayInfo();
    AssayInfo.IVolume = volumeInfo;
    CartridgeStepStatus StepStatus = new CartridgeStepStatus();
    StepStatus.Data = AssayInfo;
    await Task.Run(() => _instrument.ProcessCartridge(StepStatus));
}

这是每当我得到它时的回电我正在更新属性

public void ProcessCartidge<T>(T data)
{
    InstrumentCallBackPropertiesInstance.RunStepStatusName = data.ToString();
}

Answer 1

您可以将BackgroundWorker替换为Task.Run，因为它与async和await无效。

Task.Run启动后台线程，并且应该包含需要在单独的线程上运行的代码。如果要报告进度，则应使用IProgress参数。

这个例子可以让你朝着正确的方向前进。您可以基于此构建最终解决方案。

protected override async void OnLoadAsync( EventArgs e )
{
    base.OnLoad( e );

    try
    {
        IsLiveProgress = true;
        await StartCurrentRunAsync( true );
    }
    catch ( Exception ex )
    {
        CreateEventLogs.WriteToEventLog( string.Format( "{0} - {1}" , "Error occured during Run" , ex.Message ) , LogInformationType.Error );
    }
    finally
    {
        IsLiveProgress = false;
    }
}

private Task StartCurrentRunAsync( bool obj )
{
    StartTimer();
    PropertyCallBackChangedInstance.PropertyChanged -= PropertyCallBackChangedInstance_PropertyChanged;
    WhenCancelledBlurVolumesGrid = false;
    OriginalTime = SelectedVolumeEstimatedTime();

    return Task.Run( () =>
    {
        CreateEventLogs.WriteToEventLog( string.Format( "Run with Assay:{0} Volume{1} has been started" , SelectedAssay , SelectedVolume ) ,
            LogInformationType.Info );
        var instance = ConnectToInstrument.InstrumentConnectionInstance;
        return instance.InitalizeRun( PopulateRespectiveVolumes() );
    } );
}

private void PropertyCallBackChangedInstance_PropertyChanged( object sender , PropertyChangedEventArgs e )
{
    //bool stepDone = false;
    if ( e.PropertyName == "RunStepStatusName" )
    {
        var value = sender as InstrumentCallBackProperties;
        Dispatcher.CurrentDispatcher.BeginInvoke( ( Action ) ( () =>
        {
            CurrentStatus = value.RunStepStatusName;

            if ( value.RunStepStatusName == "Step5" )
            {
                WorkDone = true;
            }
        } ) );
        //stepDone = true;
    }
}

后台工作程序不会更新UI并进入无限循环

1 个答案: