Is XForms still a live standard? - standards

The XForms standard page seemed to indicate that it was no longer live, and that html5 kinda sorta does the job now. Is this the case? I'm looking at storing heterogenous data nuggets as XML fragments - generating a editor page according to the datatype.

To add to Phil's answer:
The XForms Working Group at W3C is active and currently working on XForms 2.0. See in particular the proposed 2.0 features on the wiki and the in-progress draft of the spec as of Feburary, 2012.
Also I don't think it's fair to say that HTML 5 "does the job". HTML 5 forms bring small and welcome improvements over HTML 4 forms, but they don't bridge the gap with XForms.
XForms on the other hand provides:
MVC architecture
XML data model (you like it or you don't, of course)
a powerful repeat model with xf:repeat
declarative properties and calculations
declarative event handlers
integration between the data model and REST services with xf:submission
built-in notion of hint, help, and alert messages
And I am probably missing some.
UPDATE 2016-11-28: For an answer up to date as of the end of 2016, please see this newer question.

The standard definitely isn't dead, although it's perhaps true to say that it hasn't gained much traction within the standard web-browsing ecosystem.
I have worked on a number of projects where XForms has been used as the forms layer in some bespoke application; in my cases the XForms parts have been handled by either Backplane BX or Ubiquity XForms, both of which may be worth taking a look at depending on your requirements (full disclosure: I've worked in the past as an implementer on both projects). Backplane BX is Windows/IE specific; Ubiquity XForms is a cross-browser, client-side javascript library; both are open source.
There are also a number of other libraries that I've not worked with but which I've heard good things about: Orbeon and XSLTForms spring to mind, but a more complete, albeit slightly outdated, list can be found here.

Related

Design and Modelling for DexExpress eXpressApp Framework

The DevExpress XAF does much basis work for you, it creates a database based on your business objects, and dynamically generates a UI based on these, with basic functions like add, delete, sort etc. already present.
This leaves me wondering how to go about properly designing and modelling an application built on this framework. I could only model my business objects, or I could identify functions provided by the framework and include them in a details model down to sequence diagram level, but so much is being done by 'external' calls that I feel I would be wasting valuable time.
I am hoping someone with experience modelling application designs for this specific framework can give me some advice on what areas I should focus on.
As for DC, as Leon mentioned above, it has many benefits compared to the regular persistent classes. If all goes according to plan, we will release the Domain Components technology in the near future, and resolve all the remaining issues with it.
If you feel that it is hard to learn, please let us know the most difficult parts you experienced. We will be glad to review them and possibly make the things easier for you and other users.
P.S.
I apologize for the delay in responding; I was on sick leave. You will receive more timely responses if you post your questions in the DevExpress Support Center.
#ProfK:
Am I correct that you are looking for something like visual designer for your business models?
If so, then I am afraid that XPO (XAF) does not currently provide such a functionality. However, you can use free third-party tools for modeling, such as Liekhus ADO.NET Entity Data Model XAF Extensions
I hope you find this information helpful.
I'm using XAF for almost two years now and I'm very happy with it. Developing an app is very quick, nice architecture, both Win and Web the same time and great UI. As with all frameworks, it has a learning curve, but if your already familiar with DevExpress controls that it's not very hard.
As Dennis mentioned, most behaviour can be overriden or extended. Regarding your modelling question, if think an important choice you have to make is whether or not you will use their Domain Components technology. Basically they have 2 ways: the old fashion way by inheriting from the XAF or XPO base classes or by using DC. DC allows a clean separation in modules and allows multiple inheritance. They can do that by generating classes runtime, but it still has some issues.
And the framework comes with a Business Class Library, a set of common classes which may be useful.
When I get stuck or cannot find the answer myself, I always use their fantastic Support Center. Most issues I ran into were already asked and answer on that site.
Briefly, each XAF application consists of Modules. There can be standard (system) and extra (user-defined) modules. Each Module can contain business objects, so-called Application Model customizations, Editors, Controllers, and Actions to provide additional business logic, customize UI and provide interaction between framework parts. You can model and customize your application on each level listed above, including but not limited by the underlying framework's metadata and data store ones. You can find more information about the framework's architecture here:
http://documentation.devexpress.com/#Xaf/CustomDocument2559
I should emphasize that it is possible to override behavior of almost every part of the framework. For instance, create your own editors for detail and list forms, override certain standard controllers, etc.
If you experience any further difficulties with our framework, feel free to contact us through our Support Center. We will be always glad to not only answer you questions, but advice a certain technical or design solution, provide some example code, etc.

robust server side dynamic form engine for ASP.NET

I've recently implemented a simple dynamic forms engine that uses dynamically loaded ASP.NET controls in concert with an EAV schema to handle the variable nature of the data model. The business was sufficiently satisfied with the end product for a time, but is now clamoring for much more complex dynamic forms:
Field visibility is tied to the values of other form fields
List of drop down possible values tied to the state of other form fields
Enforcement of various business rules across the form: i.e. Value of FieldA must be no greater than FieldX + 30 days, assuming FieldX is not null, blah blah
Other complex inter-field dependencies and business rules
As you might imagine, I'm looking for an off the shelf solution since rolling such an engine from scratch seems tedious, time consuming and not really part of our core business. Ideally, I want complete ASP.NET framework (MVC or WebForms) that encompasses all layers (Business Logic, Presentation Layer and Persistence). Beggars can't be choosers, however, so I'd make do with a framework that only dealt with Business Rule definition and evaluation. Furthermore, I'm looking for a strictly server-side solution since my hands are tied by a strict policy that disallows any dependence on client side plug-ins.
XForms seems like a perfect fit, but the only mature implementations I've found are based on Java (Orbeon) or Django (Chiba). The other XForms implementations I've found have some kind of dependence on client-side plug-ins.
I'm open to using Orbeon if I can figure out a way to integrate it with an ASP.NET application, but I've see no actual examples of such a hybrid implementation.
I looked briefly at Microsoft Office InfoPath, but it doesn't seem nearly robust enough to handle the kind of complex scenarios I need to implement.
All ideas welcome!
You should have a look at betterform (http://betterform.de) too. It's a successor of Chiba and has many improvements in comparison to the original Chiba. It is open source and hosted at sourceforge as the original product.

is it possible to use MVP pattern with Codesmith Ntier or PLINQO Template

Currently we are working on ASP .net application and i would prefer to go ahead with MVP pattern (for UI) due to several advantage it provides,
But the con of going ahead with that approach is too much of hand coding which will eat up time.
I already identified that it is possible to generate DAL with any template or by using LINQ to SQL but the only issue is with generating interface which should be implemented by usercontrol (view) and some boilerplate code (for data binding)
Now the question is
1) Is it possible to use codesmith template to get the MVP pattern (To generate interface & properties at UI layer as well as data binding)
2) It is not advisable to go ahead with MVP pattern and use the simple approach provided by codesmith template generator or any other tool
Note : I have also considered to go ahead with ASP .Net MVC but due to lack of knowledge (learning requirement) and project time line we have to drop that idea.
EDIT : In terms of man month effort it is of around 35-40 man month's effort to develop this application
Please suggest me.
1) Absolutely possible. The "how" depends quite a lot on what specifically you are doing and how well templates fit your patterns (or how well your needs can be distilled to code generation in general).
2) Impossible to say. Depends entirely on your needs.
You should really investigate ADO.NET Data Services and ASP.NET Dynamic Data Scaffolding frameworks. These are designed exactly to do the kind of generation you are asking for.
A bit late but checkout the codesmith templates I just released.
http://community.codesmithtools.com/CodeSmith/m/templates/42499.aspx

What's the best way to target both WPF and Web apps?

We are currently designing a business application that has two primary requirements for it's UI:
1) run on the Desktop (WPF) for enterprise users to provide a rich user interface, interoperate with other applications, access the filesystem, work offline, work with special local hardware, etc.
2) run on ASP.NET/Ajax to provide several components of this application to customers (internet). Unfortunately Silverlight is not (yet) an option.
Even though we don't have to make the full application available on the web, some of these components are fairly complex and we would like to share as much UI code as possible with the WPF implementation.
What options do we have to reach this goal? Is there a pattern that works well with both technologies?
Update:
Thanks for the answers even though they don't include the one I was looking for! :)
I don't think UI generators are a good option. Like Eduardo pointed out you will probably end up with problems in both worlds. I will check out Sculpture though.
I've been thinking along these lines for a while now, and I've yet to come up with a great answer. That being said, here are some of my thoughts:
If you used some variation of the various MVP/MVC/MVVM UI methodologies and you were very disciplined in this approach (i.e. not mixing presentation stuff with behavior stuff), you'd probably be farther down the road.
You might consider investigating the various DSL toolkits that have cropped up, the idea being to create a simple "language" to describe your UI at a high level and generate a representation of that UI in WPF/ASPX.
Also, I ran across this recently. I have no idea how good it is. I'm planning to take a closer look when I get the chance.
Good luck!
The unfortunate truth is that Asp.net/ajax (the web in general for that matter) and WPF (and heck, let's throw WinForms in there for good measure) have very different User Interface models and what works well for one is not necessarily going to work well for another. That's not to say that you can't share logic between applications written for either technology, but, I'll make a stretch here, your UI logic is not going to be in that category.
I've been using a variation of MVVM for WPF and ASP.Net MVC most recently and I'd say they are very good fits for the technology at hand. However, while they are very similar, they have their differences and I'm not sure you could write an abstraction layer (in any decent amount of time) that could take advantage of the great features in both technologies.
Ultimately, I'd say that your best bet is to follow some SOA patterns and extract as much of your business and data access logic into common libraries as possible. Then, write separate user interfaces in WPF and Asp.net to take advantage of those common libraries. This is the approach that my company is taking at the moment, and it's working like a charm.
It may seem daunting to write your UI logic twice (once for asp.net and once for wpf), but I think it's worth it so that your code can fit the patterns and practices that best fit those technologies.
As an aside, even though Silverlight is not an option, have you considered XBAP?
If a former job we did something similar. As Daniel Pratt says, we describe our interfaces in XML and then a render will create the form, report or whatever we decided to create.
We have to provide a Javascript function to do some UI validations in the HTML render, and a call to a java function in the Swing render.
Beware that you may end with imperfect apps in both worlds.

Productivity gains of using CASE tools for development

I was using a CASE called MAGIC for a system I'm developing, I've never used this kind of tool before and at first sight I liked, a month later I had a lot of the application generated, I felt very productive and ... I would say ... satisfied.
In some way a felt uncomfortable, cause, there is no code and everything I was used to, but in the other hand I could speed up my developing. The fact is that eventually I returned to use C# because I find it more flexible to develop, I can make unit testing, use CVS, I have access to more resources and basically I had "all the control". I felt that this tool didn't give me confidence and I thought that later in the project I could not manage it due to its forced established rules of development. And also a lot of things like sending emails, using my own controls, and other things had their complication, it seemed that at some point it was not going to be as easy as initially I thought and as initially the product claims. This reminds me a very nice article called "No Silver Bullet".
This CASE had its advantages but on the other hand it doesn't have resources you can consult and actually the license and certification are very expensive. For me another dissapointing thing is that because of its simplistic approach for development I felt scared on first hand cause of my unexperience on these kind of tools and second cause I thought that if I continued using it maybe it would have turned to be a complex monster that I could not manage later in the project.
I think it's good to use these kind of solutions to speed up things but I wonder, why aren't these programs as popular as VS.Net, J2EE, Ruby, Python, etc. if they claim to enhance productivity better than the tools I've pointed?
We use a CASE tool at my current company for code generation and we are trying to move away from it.
The benefits that it brings - a graphical representation of the code making components 'easier' to pick up for new developers - are outweighed by the disadvantges in my opinion.
Those main disadvantages are:
We cannot do automatic merges, making it close to impossible for parallel development on one component.
Developers get dependant on the tool and 'forget' how to handcode.
Just a couple questions for you:
How much productivity do you gain compared to the control that you use?
How testable and reliant is the code you create?
How well can you implement a new pattern into your design?
I can't imagine that there is a CASE out there that I could write a test first and then use a CASE to generate the code I need. I'd rather stick to resharper which can easily do my mundane tasks and retain full control of my code.
The project I'm on originally went w/ the Oracle Development Suite to put together a web application.
Over time (5+ years), customer requirements became more complex than originally anticipated, and the screens were not easily maintainable. So, the team informally decided to start doing custom (hand coded) screens in web PL/SQL, instead of generating them using the Oracle Development Suite CASE tools (Oracle Designer).
The Oracle Report Builder component of the Development Suite is still being used by the team, as it seems to "get the job done" in a timely fashion. In general, the developers using the Report Builder tool are not very comfortable coding.
In this case, it seems that the productivity aspect of such CASE tools is heavily dependent on customer requirements and developer skill sets/training/background.
Unfortunaly the Magic tool doesn't generates code and also it can't implement a design pattern. I don't have control over the code cause as i stated before it doesn't have code to modify. Te bottom line is that it can speed up productivity in some way but it has the impossibility to user CVS, patterns also and I can't control all the details.
I agree with gary when he says "it seems that the productivity aspect of such CASE tools is heavily dependent on customer requirements and developer skill sets/training/background" but also I can't agree more with Klelky;
Those main disadvantages are:
1. We cannot do automatic merges, making it close to impossible for parallel development on one component.
2.Developers get dependant on the tool and 'forget' how to handcode.
Thanks

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