Call WebView page method from referenced WinRT Component with AllowForWeb class

I have a XAML page with WebView inside (for example MainPage.xaml). Also I have WinRT Component with class marked with [AllowForWeb] attribute. This component is referenced from project where MainPage.xaml located and in code-behind AddWebAllowedObject method is used. And I can't reference main project back because of circular dependency.

How to call MainPage.xaml.cs methods from component class? Very usual situation. Is there are some standard way to do it?

For example. I have a method inside RT component that could be called from JavaScript

     public void ShowMessage(string message)
    {
       // I want to call here function from MainPage.xaml.cs
    }

Thankfully to @Elvis Xia who has gived me idea, I has found a solution how to do it without C++.

I have create a third project as Class Library. It doesn't has restrictions to use Action. This library I have referenced from main project and from WinRT component. Code of class inside library:

    public class BridgeClass
{
    public static event Action<string> MessageReceived;

    public static void Broadcast(string message)
    {
        if (MessageReceived != null) MessageReceived(message);
    }
} 

Code inside main project with webview is:

  // place somewhere 
  BridgeClass.MessageReceived += ShowMessage;

  // ....... and add a method
   void ShowMessage(string msg)
    {

    }

And now i can call this code from WinRT component:

 public void ShowMessage(string message)
{
      BridgeClass.Broadcast("lalala");
}