Topic: He made it there again

[LE3]

It is a preview...

http://through-the-interface.typepad.com/through_the_interface/2010/07/preview-of-augusts-plugin-of-the-month-refucsspy.html

Kudos Glenn R. !

[vegbruiser]

Aye, well done that man!

[Glenn R]

Thanks lads - just a little something to share with the community.

[It's Alive!]

Nice work, even though it demonstrates pointless and wasteful event handling 

[Glenn R]

Yeah, pisser about that eh? Funny, but that's how you do it in ARX as well if memory serves...go figure...

[It's Alive!]

You always do top notch coding, thanks for sharing your talents   

[Glenn R]

Thanks for the kind words Dan and glad to help where I can.

[Bryco]

Well done Glenn.
I see you didn't dispose the TaskDialog, is there no need?
I ask as they look kind of handy and I'll probably start using them a bit.

[Glenn R]

Thanks Bryce. From memory, TaskDialog doesn't implement IDisposable. When I wrote this, I automatically wrapped it in a 'using', which went bang with a nasty compiler error the first time I compiled.

[kaefer]

Hello, friends!

I'm new here and this is my first post.
My question is: What are your opinions on using Observables for event handlers, now available in .NET 4.0?

As an example take the DocData class inspired by Glenn's RefUcsSpy and Tony's subsequent comments.
Alas, it is not C#, it's in F#; but should be straightforward to port.

Code: [Select]

type DocData(doc: Document) =
    let obs =
        doc.CommandWillStart
        |> Observable.filter
            (fun e ->
                DocDataModule.Contains e.GlobalCommandName &&
                not acadApp.WcsCurrent &&
                not acadApp.ScriptActive &&
                DocDataModule.RequestUserConfirmation() )
        |> Observable.subscribe
            (fun _ ->
                let ucsFollow = acadApp.UcsFollow
                let currentUCS = doc.Editor.CurrentUserCoordinateSystem
                let commandEnded = ref null
                commandEnded :=
                    doc.CommandCancelled
                    |> Observable.merge doc.CommandEnded
                    |> Observable.merge doc.CommandFailed
                    |> Observable.subscribe
                        (fun _ ->
                            acadApp.UcsFollow <- ucsFollow
                            doc.Editor.CurrentUserCoordinateSystem <- currentUCS
                            (!commandEnded).Dispose() )
                acadApp.UcsFollow <- false
                doc.Editor.CurrentUserCoordinateSystem <-
                    Matrix3d.Identity )

    member x.Stop() =
        obs.Dispose()

Look ma, no mutable state.