Question

使用Prism4和MEF我创建了一个shell和两个模块（M1，M2）。

我确实想在M1中打开一个串口，并使用一个接口，从打开的串口发出一个带有数据的事件，我希望M2得到通知，并从串口接收数据。

更具体地说，我使用MVVM模式，因此我想在M1的ViewModel中打开串口，并在收到数据时通知M2的ViewModel。

不幸的是，我很不确定如何在PRISM工作流程中使用该界面。我很感谢每一个帮助。我真的需要一个这个问题的例子。我添加了代码只是为了让我的问题清楚。

提前致谢。

模块A.cs

[ModuleExport(typeof(ModuleA), InitializationMode = InitializationMode.OnDemand)]
public class ModuleA : IModule
{
    [ImportingConstructor]
    public ModuleB(IEventAggregator eventAggregator_)
    {
        EventAggregator = eventAggregator_;

    }

    [Import]
    public IRegionManager RegionManager { get; set; }


    public void Initialize()
    {

        this.RegionManager.RegisterViewWithRegion("RegionA", typeof(ZeroGrid1));

    }
}

模块B.cs

[ModuleExport(typeof(ModuleB), InitializationMode = InitializationMode.OnDemand)]
public class ModuleB : IModule
{
    [ImportingConstructor]
    public ModuleB(IEventAggregator eventAggregator_)
    {
        EventAggregator = eventAggregator_;

    }

    [Import]
    public IRegionManager RegionManager { get; set; }


    public void Initialize()
    {

        this.RegionManager.RegisterViewWithRegion("RegionB", typeof(ZeroGrid2));

    }
}

ZeroGrid1.xaml.cs（类似于ZeroGrid.xaml.cs）

[Export]
public partial class ZeroGrid1
{
    [ImportingConstructor]
    public ZeroGrid1(ZeroGridViewModel1 viewModel)
    {
        InitializeComponent();
        this.DataContext = viewModel;
    }
}

ModuleAViewModel.cs

[Export]
public class ModuleAViewModel: NotificationObject, IDataReciever
{
// OPEN SERIALPORT
//SEND SOMETHING SERIALPORT
//Maybe I also wanna get notification for datareceived here
}

ModuleBViewModel.cs

[Export]
public class ModuleBViewModel: NotificationObject, IDataReciever
{
//GET NOTIFIED WHEN DATARECEIVED FROM SERIALPORT AND RECEIVED DATA
}

IDataReceiver.cs

interface IDataReciever<TData>
{
event Action<TData> DataRecieved;
//some other methods, such as, for example:
//void Open();
//void Close();
}

Answer 1

通过导出从Prism的'CompositePresentationEvent'派生的类来定义复合演示事件，其中T是事件“有效载荷”的类型。

[Export]
public class DataReceivedEvent : CompositePresentationEvent<object>
{}

让您的两个ViewModel导入该事件：

[Export]
public class ModuleAViewModel: NotificationObject, IDataReciever
{

    private DataReceivedEvent _dataReceivedEvent;

    [ImportingConstructor]
    public ModuleAViewModel(DataReceivedEvent dataReceivedEvent)
    {
        _dataReceivedEvent = dataReceivedEvent;
        _dataReceivedEvent.Subscribe(OnDataReceived);
    }

    private void OnDataReceived(object payload)
    {
        // Handle received data here
    }

    // This method gets called somewhere withing this class
    private void RaiseDataReceived(object payload)
    {
        _dataReceivedEvent.Publish(payload);
    }
}

在ViewModelB中执行相同的操作，如果在应用程序中的任何位置引发事件，则会收到通知。

Answer 2

MSDN 中提供了 QuickStart 解决方案，该解决方案描述了如何从一个模块发布事件并从另一个模块订阅它。您可以在以下棱镜指南附录中找到事件聚合快速入门：

Appendix G: QuickStarts - Event Aggregation QuickStart

有关 EventAggregator 的工作原理的详情，请参阅以下棱镜指南一章：

Communicating Between Loosely Coupled Components

问候。

带事件的复合WPF GUI界面

2 个答案: