Can an event be used as an event listener?
I'm trying to expose some events from a private object which is contained inside the object I am creating and it looks like the compiler is happy with this:
private WindowUpdateServer _windowUpdateServer;
public event WindowUpdateHandler WindowUpd开发者_JAVA技巧ated;
public RecieveWindowFramesManager() {
_windowUpdateServer = new WindowUpdateServer();
_windowUpdateServer.ExistingWindowUpdated += WindowUpdated; // ExistingWindowUpdated is a WindowUpdateHandler
}
But after RecieveWindowFramesManager is initialized _windowUpdateServer.ExistingWindowUpdated == null.
Am I missing something here - it seems this should work?
It is worth noting that after RecieveWindowFramesManager is initialized I attach an event listener to WindowUpdated but it never gets called (even though _windowUpdateServer.ExistingWindowUpdated gets fired).
I'm not sure, but I think this only assigns those handlers from the WindowUpdated event, that were set when the += operation took place. Since it is a constructor, the list was empty. To do what you want, create your own event handler for ExistingWindowUpdated and fire the WindowUpdated event from there.
I'd do something like this:
public event WindowUpdateEventHandler WindowUpdated
{
add{ _windowUpdateServer.ExistingWindowUpdated += value; }
remove{ _windowUpdateServer.ExistingWindowUpdated -= value; }
}
It has some issues if you're actually using the sender argument in the event handlers, though; it'll point to the inner object rather than the one you're getting the events from.
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