I assume that you're talking about the '.ddb' and '.csb' files mentioned in the document, correct?
Actually there is very little difference between these files types, or for that matter, any of the so-called 'UI object' files described in the document that Joe pointed you toward. The different extensions were assigned more as an aid in helping developers to better understand what they were creating these files for and also so that the system knew exactly how to handle them if and when they're referenced. It's interesting that you're focusing on the TWO files types that we ourselves have NOT done that much with (in fact, there's only a single '.csb' file in NX 9.0 and just four '.ddb' files). The reason for that is that you can create Drop-Downs/Cascades inside of a Ribbon Tab, '.trb' file, just like you were able to define a 'cascade' in a '.men' file and 'dropdowns' in '.tbr' files. The real reason for now having explicit '.ddb' and '.csb' files, even if we've not chosen to use them much, was to provide developers with the flexibility to create 'UI Objects' which could be reused in more than one place. An example might be that rather than cloning the text to create the same 'dropdown' in two different Ribbon Tabs, I could create a single '.ddb' file which I just referenced from two (or more) '.rtb' files. That way I could change the content of all instances of that user-defined 'dropdown' by editing a single file.
So I guess the bottom line is that you can use them or not, it's up to you and the type of customization that it is that you're attempting to do. That being said, due to the fact that most people who are interested in customizing the NX 9.0 UI may not be replacing big chunks but more likely simply wanting to add some of their own special functions and/or user-developed applications, that our users just might benefit more from using these various files then we would since they can then be easily added to an existing Siemens created '.rtb' file by just making a single reference, eliminating the need to add large amounts of explicit text.
Anyway, I hope this helps remove some of the confusion that you might have over this group of new file types that we added to the mix, as it were.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
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