Caliburn.Micro WPF：如何创建具有依赖关系的新 ViewModel？

Question

我创建了一个名为 ShellView 的窗口，它将加载或处理两个名为 AView 和 BView 的用户控件。

我已经有了这个设置：

Bootstrapper.cs

public class Bootstrapper : BootstrapperBase
{
    private SimpleContainer _container = new SimpleContainer();

    public Bootstrapper()
    {
        Initialize();
    }

    protected override void OnStartup(object sender, StartupEventArgs e)
    {
        base.OnStartup(sender, e);
        DisplayRootViewFor<ShellViewModel>();
    }

    protected override void Configure()
    {
        _container.Singleton<IWindowManager, WindowManager>();
        _container.Singleton<IEventAggregator, EventAggregator>();
        _container.RegisterPerRequest(typeof(ShellViewModel), null, typeof(ShellViewModel));
    }

    protected override object GetInstance(Type serviceType, string key)
    {
        return _container.GetInstance(serviceType, key);
    }

    protected override IEnumerable<object> GetAllInstances(Type serviceType)
    {
        return _container.GetAllInstances(serviceType);
    }

    protected override void BuildUp(object instance)
    {
        _container.BuildUp(instance);
    }
}

AViewModel.cs

public class AViewModel : Screen
{
    private IEventAggregator _eventAggregator;

    public AViewModel(IEventAggregator eventAggregator)
    {
        _eventAggregator = eventAggregator.
    }
}

这就是问题所在，如何在 ShellViewModel 中传递事件聚合器的实例？

ShellView.cs

public class ShellViewModel : Conductor<Screen>
{
    public ShellViewModel()
    {
        // Should I create an instance and pass it in? If not, how?
        ActivateItem(new AViewModel(?));
    }
}

Answer 1

Caliburn.Micro 为此有一个名为IoC 的静态类。你应该这样做：

ActivateItem(IoC.Get<AViewModel>());

如果有意义的话，您也可以这样做：

public class ShellViewModel : Conductor<Screen>
{
    private IEventAggregator _eventAggregator;

    public ShellViewModel(IEventAggregator eventAggregator)
    {
        _eventAggregator = eventAggregator;
        ActivateItem(new AViewModel(_eventAggregator));
    }
}