The Building Coder

Filter for Views and the IsTemplate Predicate

Several people encountered issues when retrieving views in Revit 2011. The reason is that the most direct approach to filtering for view elements using the new element filtering also returns view templates, which were not accessible in the Revit 2010 API. Here is the initial issue: Question: I tried to extract all PlanView elements from the model and found something weird: besides the expected and obvious plan views such as Level 1, Level 2 and Site, some other unexpected ones... Read more →

Add-In Manifest and Guidize

Developers have always had a lot of complaints about the Revit.ini add-in registration facility. It was hard to access and modify the file in the Revit installation directory and the same file is shared by all users. Revit 2011 offers a completely new and vastly improved add-in registration facility using add-in manifest files. The new mechanism supports a number of new options and there is no reason to continue using the obsolete Revit.ini mechanism. Let's have a look at this... Read more →

Asynchronous API Calls and Idling

I discussed the Idling event yesterday, and since received a note from the venerable Revit API guru Guy Robinson who finds this new event just as momentous and exciting as I do and therefore promoted it to the Revit 2011 API standout feature. If Guy likes it, it's the real thing, for sure. Since this once again dives full into the topic of controlling Revit from an external application or a modeless dialogue, here is a very apt comprehensive summary... Read more →

Idling Event

One of the most exciting of the many new Revit 2011 API features which opens up completely new possibilities for applications to interact with Revit is the Idling event. The What's New section of the Revit API help file RevitAPI.chm describes it as follows: The new event UIApplication.Idling is raised when it is safe for the API application to access the active document between user interactions. This event is raised only when the Revit UI is in a state where... Read more →

Matt Mason's API News

I just noticed from Matt Mason's comment on the plug-in migration steps that he is running a very interesting series of posts on the new Revit 2011 API as well. Here is his current table of contents: Upgrading Existing Revit API commands/applications New Deployment Methods The New UI vs. Database split. New Ribbon Capabilities Element Iteration Changes Ooh-ooh Pick Me! New Selection Methods Dynamic Model Update Event Model Changes RevitLookup: The New RevitMgdDbg What’s New in Element Creation? What Kinds... Read more →

Failure API

A very frequent question from developers in the past has been about suppressing various warning and error messages in Revit. One of the many new Revit 2011 API features specifically targeted at allowing an add-in to integrate very tightly with Revit and its user interface is the new Failure API, providing the ability for an add-in to react to and suppress failures as well as define its own new ones and post them. This is the description in the What's... Read more →

Plug-In Migration Steps

We discussed the migration of The Building Coder samples from the Revit 2010 to the Revit 2011 API and noted some of the required steps there, but skipped a lot of the obvious and onerous detailed information. Luckily, my colleague Joe Ye was more patient and precise when he migrated our Revit Structure labs and analysis link sample, and kept track of the required steps in great detail. So, without further ado, here are Joe's Revit 2011 plug-in project migration... Read more →

Regeneration Option Best Practices

Our discussion of the risks of using the manual regeneration option triggered several very interesting comments and suggestions. Here are some important fundamental things to note about the regeneration modes: The automatic mode is not new. It is the mode that Revit has been using all along so far. Developers complained that it is too slow, so we introduced the SuspendUpdating mechanism and now the manual option, providing more and more optimisation possibilities. There is no need to overcomplicate things.... Read more →

Revit 2011 API Webcast

Here is a last-minute reminder to register for the Revit 2011 API webcast that we are holding on Wednesday April 21st, in eleven hour's time. To register, you can visit the Autodesk Developer Network (ADN) DevTech API training schedule site, filter for 'Revit 2011 New APIs', and click on the register link. This webcast is open to all developers, regardless of ADN membership. Sorry for the late notice, I was too caught up in the discussion on the regeneration option... Read more →

Retrieve Stairs on Level

As mentioned in the discussion on selecting model elements, stairs are not represented by an own class in the Revit API, but using the generic Revit Element class instead. They do have a valid built-in category assigned to them, however, which makes it easy to retrieve them from the database and use the generic element and parameter access to retrieve and modify a lot of their data. We also discussed other aspects of stairs in the past, such as listing... Read more →

Manual Regeneration Option Danger

Here is a serious issue that several developers have already run into when migrating to the Revit 2011 API, including myself. It sometimes causes pretty obscure errors which are hard to understand and very easy to resolve, once you understand the source. Obviously it is best and most efficient to completely avoid running into the problem at all, which I hope this post will help you do. The issue is the regeneration option, one of the required attributes that must... Read more →

Retrieving Newly Created Elements in Revit 2011

Here is a largish post which will hopefully keep you happily occupied over the weekend. We looked at the topic of retrieving newly created elements in Revit 2010 last year. Since the method presented there is based on simply retrieving sequential entries from the Revit element collection, and that collection is no longer directly accessible in Revit 2011, I was curious to see whether the approach presented there would still work. To my surprise, with some adaptation, it really does.... Read more →

XYZ Immutable

As mentioned in the overview of the Revit 2011 changes, new classes for XYZ, UV, and ElementId were introduced in the Revit 2011 API. These ubiquitous objects have been promoted to classes now, some of their methods renamed, and generic .NET collections replace many of the custom Revit collection classes. The Revit API help What's New section describes these changes in some more detail. One of the changes which may affect existing code is the immutability of the XYZ coordinate... Read more →

Debugging with Visual Studio 2010 and RvtSamples

Rod Howarth just published a description of a problem debugging a Revit 2011 add-in with Visual Studio 2010. He found a related thread on the Microsoft Connect Visual Studio discussion forum describing the same issue with Revit 2010 and presenting a solution for it: The issue that you are encountering is that Visual Studio 2010 is launching Revit under the default debugger (v4.0) but since you are building a project against the 2.0 framework (3.5 runs on the CLR 2.0)... Read more →

Public Revit 2011 SDK Posting

The Revit 2011 SDK is now available on the public Revit Developer Center site. Here are some of the last-minute changes documented between the beta version and this one: Refactored Document properties related to transactions Two existing properties have been re-implemented to better complement the changes in the transaction framework: Document.IsReadOnly indicates that a document is in read-only state, either temporarily or permanently. If it is read-only, new transactions may not be started in that document, and thus the model... Read more →

Element Level Events

From my point of view, one of the most important enhancements to the Revit API is the availability of element level events. This allows an application to react to modifications to the database, including tracking changes to individual elements. The Revit 2011 API provides not just one but two separate mechanisms to subscribe to element level notification events: Elements changed event Dynamic model update Elements Changed Event The new Application.DocumentChanged event is raised after every transaction is committed, undone, or... Read more →

ElementId Parameter Value

This week I should be recording the VBA migration guide DevTV in German, and once again I cannot keep away from blogging instead. This is just a short and sweet little support case that I thought worth while describing for the general public: Question: I am interested in the possible values of some specific parameters whose storage type is ElementId. One of them is the 'Start Connection' parameter on beams. If I want to set that parameter to something, I... Read more →

User Visible Enumeration Value Labels

The first Revit 2011 Programming Introduction class in Warsaw last week went well. In a way, it was quite an extreme event, because on one hand the training material is still new and under development for updating to the new version, and on the other, we had 40 participants, which is the largest group I have ever led single-handedly through a hands-on programming training. So I was pretty busy and very happy that all were satisfied. Getting back into everyday... Read more →

Beam Requires Curve

We discussed the issue of inserting a beam and also creating a curved beam in some depth already. The former discussion includes a pretty detailed analysis showing that you really do have to specify a curve in order to generate a valid beam instance, and all other overloads of the NewFamilyInstance will fail in one way or the other. In spite of this, people continue having problems inserting beam instances. My colleague Joe Ye just encountered another case like this:... Read more →

RevitAddInUtility

In a comment on the recent discussion of the Revit 2011 product GUIDs, David Bartliff raised an interesting question on the new Revit add-in utility DLL which triggered some internal discussion as well. Before addressing David's question, however, let's look at some background info on what this utility is about at all. Revit Add-In Utility DLL The Revit add-in utility DLL is a stand-alone .NET assembly which offers a dedicated API capable of reading, writing and modifying add-in manifest files.... Read more →

RevitLookup and TextNote Alignment

To take a break from all the exciting Revit 2011 oriented news and dash off a quick post while continuing my preparations for the Revit programming introduction workshop here in Warsaw, I thought I would simply present a recent case handled by my colleague Saikat Bhattacharya. While doing so, however, I ran into yet another 2011 related issue concerning RevitLookup, previously known as RvtMgdDbg, which I thought I should mention before diving into the details of the case. RevitLookup Both... Read more →

Anonymous Methods in VB

By the time you read this, I will be well on my way to the Revit API training that I am giving in Warsaw. The Revit API introduction labs that I am using for that include a few examples of post-processing the results of a Revit filtered collector query. I discussed several examples of such post-processing before Easter when profiling the collector performance. I and my colleagues were having some trouble converting the code from C# to VB, and I... Read more →

Collector Benchmark

After all the preparation creating a profiling tool, let us now put it to use on the Revit 2011 collectors, which is one of the areas that has been most heavily reworked in this release and at the same time affects more applications than any other, in fact just about every single one. This has led to a rather huge post for today, but I really wanted to share these important results with just as soon as possible. First of... Read more →