November, 2009

I’m taking this week off to catch up on everything I haven’t done the last two months and to celebrate the Thanksgiving holiday here in the US. PDC was a blast!  It was incredibly awesome to meet so many folks interested in WF and talking with others about how they are using (or plan to use) WF4.  I’ll be following up with a more detailed post on my talk, including demos and code, but I wanted to give a summary of the talks that came from my team at this PDC.  Below is the diagram...

One of the most commonly used designers and generally the root is the Sequence activity. Of course, we spent some amount of time adding the animation and styling to the the Sequence Activity Designer. However, due to a number of reasons(costs mainly), the activity designer is internal. However, the good news is customers can take advantage of the styling and animation that of the sequence designer so all the composite designers can avail to it and have a consistent experience throughout their workflow...

My previous post introduced the basics of how the tracking participant may be used to create custom build information through the activity context. However, as pointed out at the end of the article, the best practice for creating custom activities in Workflow 4.0 is to do so through composition, meaning that you should derive from Activity or Activity<T> . In compliance with this model we supply activities that allow you to perform the same custom information creation through activity composition...

So the last post I wrote about session wish list was a pack of lies (well the weather report was quite valid!). I skipped the code visualization talk for Christian Schormann ’s Sketchflow talk. I had been playing with Sketchflow but I had no idea you could export the entire prototype to Word to make an outline of your spec (hooray!). Also the demos that they did with coding up behaviors and drag and dropping them into the tool was really impressive. Scottgu did an awesome Silverlight demo (iPhone...

Before reading this post, you should take a moment to read Aaron Hallberg’s post on build process customization in TFS 2010 Beta 1. Now that you fully understand custom activities in Windows Workflow 4.0 (just kidding), I would like to focus on how we have made it much easier to customize the information created and stored along with the build. There are currently multiple mechanisms for getting additional information into the build process, made possible by some activities, extension methods, and...

Hello from sunny Los Angeles. I’m am shocked and pleased to be reporting to you from a place in a convention hall with actual daylight streaming through windows!!! I find all the besweatered locals amusing, personally I am wishing I brought shorts and I am wondering where I can suntan on breaks. I’m planning my day for Tuesday, which is the official start. I’m looking at sessions like: Lap around Windows Azure Expression Blend for Developers Sketchflow: Prototyping to the Rescue Code Visualization...

One fun thing we will be doing this year is using the theater in our lounge/booth area to have a few chalk style presentations.  These will be brief 30 minute demo/ q&a / conversation sessions with somebody from the product team.  These will dive a little deeper and be more interactive about topics we know you’re interested in.  We’d love you to come and just ask a ton of questions here: Thursday, 11:00-11:30 / Future Directions for State Machine Workflows  / Alan Ko Discuss...

As part of workflow authoring, it is always the case where the customer says, I like your out of box activity, however it has too many arguments/properties. I don't want to ask my user to set all these properties. And hence, now I would need to write a custom activity which has some of these properties and arguments already configured and maybe hidden as well from the user. We faced the same dilemma as we were working on our Messaging activities. We wanted the user to know about the Receive and...

The ExpressionTextBox is the basic building block for editing expressions in custom activity designers. If you’re writing a custom activity designer that uses expressions, you’ll use this control. This post is meant to provide an overview for custom activity designer developers. I’m just going to annotate a small amount of the SDK sample and walk through it step by gory step. For those with short attention spans, skip this post and just take a look at the ExpressionTextBox SDK sample instead. Start...

I’m hoping that this PDC might be a little different and I may actually get to attend some sessions, rather than just prepping for mine (or the others from my team ).  I’ve gone through all 22 pages of published talks, and I think there are some interesting ones.  So, without further ado, and with little, if any regard for actual scheduling of talks in relation to mine, here are the talks I would be interested in going to at PDC09. Hopefully I can get to 10 of them. Session Name Comment...

Lets talk about a couple of common customer scenarios/questions that I have encountered till date. 1. Workflow authors want to use the generic activities such that they can start with Activity<Object> and then dynamically without having to replace the activity on the canvas want it to be changed to Activity<string>. Specifically, this should happen without having the user to remove the activity from the canvas and then replacing it with the right generic definition, there is no simple...

In the first installment of this pre-PDC blog post series, I published the list of the sessions I’ll likely attend and a list of sessions that would be cool to see, but that isn’t really target material (for me). Microsoft has now published the time & location of each session, and I must say that [...] Blog Post by: larsw

This is what happens when you edit an expression in Visual Studio. To simplify things, pretend you started with a blank expression. Here’s what goes on behind the scenes: When you click on an ExpressionTextBox , an instance of the hostable editor is created. As you type, you will notice two things: You have IntelliSense, completion and colorization support available immediately. After a short wait, validation is called in the background. If your expression is invalid, the hosted compiler reports...

Here’s a quick one “I’d like to find out if the workflow in the designer is valid… is there someway to retrieve the validation errors?” Yes, the short answer is that you need to provide an implementation IValidationErrorService .  There is one important method to implement on this interface, ShowValidationErrors which will pass you a list of ValidationErrorInfo objects. The next thing that needs to happen is that you need to publish an instance of that new type to the editing context. Let’s...

photo courtesy of flickr user mikeweston   This is a something that the .NET team is putting together that has a contest with super cool prizes (seriously, 12 day trip to the Galapagos, for real (as my 4 year old says)).  (obligatory legalese here ). If you’ve built a sweet app with the .NET framework, we’d like to hear about it.   So check out http://www.myDotNetStory.com today and enter to win. Blog Post by: mwinkle

In this thread , one of our forum customers asked the question: “how do I find all of the variables that are in scope for a given activity in the designer?” We do not have a public API to do this.  Internally we have a helper type called VariableHelper that we use to display the list of variables in the variable designer, as well as passed into the expression text box intellisense control. One thing that I would like to point out is that if you are implementing your expression editor and want...

I’ve seen a few forum posts about providing a richer expression editing experience in a rehosted workflow designer. There are two main scenarios in which you would want to implement your own expression editor: Work around the rather unfortunate limitation that the hostable editor is not available outside of Visual Studio, so therefore there is no support for IntelliSense in a rehosted application Simplify the expression editing experience for the business analyst audience, so that analysts are not...

Here are the basic implementation details that you should know about the design time expression editing experience in the WF designer. An expression is bound to an activity argument or property. In the designer, the expressions are displayed inside of an ExpressionTextBox control. You can enter one single expression per ExpressionTextBox. Statements are not supported. The lack of statement support means that if you need to declare variables, you must declare them in the Variable designer. Inside...

Fresh on microsoft.com downloads, you can get the details of the major breaking changes that occurred for WF between Beta 1 and Beta 2. Get the document here . We will publish a similar document for any changes between Beta2 and RTM, although that list should be on the shorter side.  If you have feedback on the document, like the way something is presented or think we could have done a better job explaining it, please let me know.  Either comment here or use the “Email” link on the side...

So, we’ve reached November 1st – the day after Halloween and it’s only 15 days to the PDC! (Woohoo! ) I’m travelling with two of my colleagues and we’re staying at the Omni from the 14th, send me a message (typically on Twitter: larsw) if you want to hang out before / during the conference. [...] Blog Post by: larsw