MEF & Silverlight 4 Beta - Part 2, Imports & Exports | mtaulty

gpatnew

Very cool!

samcov
Which pill did I take?

This was a great refresher for me, however, if I hadn't been playing with MEF for awhile, I can't see how a someone new to MEF could possibly follow this.

mtaulty
Mike Taulty

In reply to samcov

#Dec 31st, 2009 @ 3:02 PM

Hi Sam,

Ah - my apologies. If you could let me know whether it's

Too fast
Too deep
Assumes too much knowledge of MEF - too little conceptual stuff up front?
Too much code
Too simple - i.e. using such a simple example causes confusion

or something else that makes this not work for you then that'd be great and I'll take that on board for future work.

If other people want to chip in as to whether they were new to MEF and whether they could follow what was going on, that'd be helpful.

Thanks,

Mike.

mike kidder

Mike I would have to disagree with Sam on this. Your video tutorials are fantastic and perfect to get a real understanding of what MEF can provide. I can only point to a hand full of video tutorials that are of this cabiler; yours is top notch!

Thank you very much for these!

Whirly101

Hey Mike,

Excellent stuff as usual. Apart from looking at part one, I haven't looked at MEF at all and I was able to follow it no problem. If the problem is lack of background, then there are better places to get the in depth theory of why MEF is useful than here. For me, it's perfect pace and content. Loving it.

Whirly.

samcov
Which pill did I take?

In reply to mtaulty

#Jan 1st @ 3:27 AM

I think you missed my point, it worked GREAT for me, but if I had seen this when I knew nothing about MEF, I don't think it would have been as effective.

I reference the pace with which you presented Unity. I had never used or looked into Unity, and I got it clear and clean.

I have to admit, this is total opinion because I can't unlearn what I already knew about MEF, so the better judge would be someone fresh to the subject.

@Mike Kidder - While you may disagree, you provided no basis for that disagreement. The only possible metric would be that you knew nothing about MEF, and got a good grasp of it here. If that was the case, you should have stated it, and if that is the case, you would be the person with the superior view of the way it was presented.

@Whirily - Perhaps if you re-read my post you might have a better understanding of what I said. Your assumption is totally off.

Too bad there wasn't a test at the end of the video, lol.

BartCzernicki

In reply to mtaulty

#Jan 1st @ 3:27 AM

@Mike,

I really liked these videos. It is probably the most detailed MEF video/intro that is out there.

MEF is not for beginers and it should be noted as an "advanced" topic. Devs who are not familiar with attributes, interfaces, lazy loading patterns, Silverlight app structure and to some extent Visual Studio 2010 are simply going to be scratching their heads after the first few minutes.

The only feedback I would give is to possibly the source code for each video (as you state, you change the code from video to video in some cases) and if someone created a lab for this that would be great as well.

The next evolution of MEF needs to be some "best practice" guidance from Microsoft on using MEF.

mglaze

Hi guys,

I'm brand new to MEF and just saw these first two videos.

First, Mike - awesome videos - I agree with everyone else here, yours is an example for all other tutorials on channel9 to follow!

Second, in response to the comments about whether a noob could follow this at all: I am definitely a noob to MEF, having never heard of it until I came across these videos. However, I'm not a junior developer at all, and I also have a good deal of experience with other Dependency Injection / Container frameworks. Currently in my projects I'm using Autofaq.

So, I've had no trouble following any of the concepts presented so far, even though its the first time I'm seeing MEF, and I've also just barely scratched the surface of Silverlight and VS2010 also. As I'm watching, I'm comparing to Autofaq and other frameworks to get a sense of how MEF offers similar features.

But I would agree, anyone completely new to both MEF and DI/IOC would probably be a bit lost, not because MEF is particularly hard to use (it's not) but because DI/IOC are pretty tough for developers to get to grips with at first, and there's really no easy way to just "dive right in" with someone who is still thinking in terms of passing dependencies around.

So far I really like what I see, but admittedly the controversy is going to come out as we get to the more advanced concepts. Looking forward to continuing on though, and I'm already considering how I could go about ripping out Autofaq and replacing it with MEF in my current project.

I do have one question though: watching these videos, and also reading through some of the content on the MEF homepage, I don't really see any mention of DI/IOC as concepts, and while most DI frameworks seem to use more or less the same terminology (Containers, Singletons, Prototypes, etc.), MEF seems to have invented a completely new set of terminology for what appear to be all the same concepts. I am still new to this, but so far my conclusion is that either (1) the developers of MEF have no idea that they are reinventing the wheel (but potentially much better); or (2) this is the intention, but all of the theoretical stuff has been purposefully left out in the videos and in the content, to avoid further confusing noobs; or (3) I'm completely misunderstanding things, and MEF is not intended to have anything to do with DI/IOC? Please enlighten me!

Thanks!

mtaulty
Mike Taulty

In reply to mglaze

#Jan 6th @ 6:46 AM

Hi,

Thanks for the feedback - really useful for me to get that view so much appreciated.

To answer your question - the answer is pretty much (2). I made a conscious decision to try and avoid saying DI and IoC with these videos. I wanted to try and introduce MEF as a practical technology for extensible applications without getting too bogged down in DI/IoC.

I made some videos about Prism and Unity and I spent maybe 1-3 whole videos trying to talk about dependencies and getting to the idea of IoC and containers like Unity and;

1) I felt that to do that again here would involve some repetition.

2) I got some feedback on those videos from some folks saying "Hey, I know what DI and IoC is - you don't need to spell it out".

3) MEF is not "just" about DI/IoC and so I didn't want to muddy the water by starting from that point-of-view.

So, I tried to do what you say in your point (2) above.

Now, I'm not a developer on MEF so I can't really answer point (1) but I can say that I feel >100% confident that the MEF guys "get it" ( a lot better than I do, I should add ) and they understand the landscape around their framework. I'd recommend looking at Glenn's blog for discussions around IoC as he has quite a lot of deep discussion on there.

Hope that helps!

Mike.