Or, how to create an event handler where there wasn't one.
So, what to do? How can I know when the window is closed? Well, a procedural programmer might simply poll the window handle periodically until the window is closed. An object-oriented programmer would decry the lack of an observer pattern in the 3rd-party's object model, and fall back to wrapping the procedural approach in a bunch of classes. What about the functional programmer? The answer looks something like this:
In the code above, getWindow returns a window object reference, 'Close' is the method called to close a window, and refreshScreen is a function object that we want to call when the close method returns. Take a moment to drink that in... What this code describes is a standard way to create your own event handler. In plain English, what the code above does (I'll show you how in a moment) can be stated as, "whenReturning from the getWindow().Close method, refreshScreen". That's powerful.
The semantics are different from wiring up event handlers; we're not making an assignment to an "OnXXXX" property of the object. In the .NET parlance, we're not making a "type safe assignment of a delegate instance to a multicast delegate". To a functional programmer, this semantic is more natural. To folks acquainted with aspect-oriented programming, this may also seem familiar. The function "whenReturning" is providing advice ("refreshScreen") at a join-point ("getWindow().Close"). In fact, this is the perspective of the article where I first picked up this technique.
If you're looking for a quick solution, you might have better luck using dojo.event.connect. Here's a snippet from their site, "[...] lets say that I want exampleObj.bar() to get called whenever exampleObj.foo() is called. We can set this up the same way that we do with DOM events:"
dojo.event.connect(exampleObj, "foo", exampleObj, "bar");
Building off of William Taysom's work, we could extend this advice to all instances of the window (RadWindow) object by modifying the prototype. That may be the subject of a future post. Until then, dear reader, best wishes.