Welcome!

Industrial IoT Authors: Elizabeth White, Stackify Blog, Yeshim Deniz, SmartBear Blog, Liz McMillan

Related Topics: Machine Learning

Machine Learning : Article

Model-View-Controller and the Brave New World of Rich Internet Applications

Many Web developers haven't heard of MVC and try to design RIAs like they would design a typical HTML app

Canoo's Web 2.0 Technology Blog on Java, AJAX and Flex

Rich Internet Applications pick up the ball where plain Web applications dropped it: they promise to bring the power of desktop applications to the Web. Desktop applications almost went out of fashion with the advent of Web applications. But most people still prefer the rich user interface (UI) and interactivity of desktop applications such as Outlook compared to their Web-based siblings such as GMail and Yahoo! Mail. In many cases the convenience of ubiquity compensates for the inferior or cumbersome user interface.

MVC diagram

Client-server applications with rich user interfaces first emerged at the beginning of the nineties. Usually implemented in C++ or Smalltalk, they followed a fat-client approach, the predominant client-server architecture at this time. The principal way to organize the presentation layer of such applications was the MVC model. The concept was first proposed by Trygve Reenskaug (see http://heim.ifi.uio.no/~trygver/2007/MVC_Originals.pdf) for the Smalltalk environment. As with any proven object-oriented design, MVC splits up the responsibilities of a user interface component into domain data (Model), rendering (View), and event handling (Controller). Quite often, view and controller are merged together, though.

Today’s GUI component libraries still make use of MVC. For example, most non-trivial UI components in Swing employ some sort of MVC. However, if one tries to apply MVC to complex (form-based) applications, which is typical for desktop or Rich Internet Applications, experience shows that criteria such as clean design, maintainability, or reusability cannot be met. There are several reasons:

  1. What is the model of a form based application with a rich UI? Most developers point to the business object to be rendered in the form as the model. A form-based RIA has more model states than just the business object, though. This additional state is usually kept in the view class and increases the complexity of the view.

  2. The presentation logic of a Rich Internet Application is vastly more complex compared to a traditional Web application. The presentation logic has to deal with more events caused by extended interactivity. Another feature of RIAs is an up-to-date rendering of the presentation state. For example, UI components may be enabled/disabled or visible/invisible depending on the state of the application. This is also part of the additional model state as mentioned above. On top of that, RIAs feature instant validation (without interrupting a user’s flow of work by throwing a modal dialog into their face). This “silent” validation has to be handled (at least partly) by the presentation logic as well. Naïve design puts all of these aspects into the view class. As a result, the view class becomes overly complex, hardly reusable, and difficult to maintain.

  3. Automated testing of such view classes can only be accomplished by running the user interface. Tests are executed by triggering user events through a test tool or accessing the components through a library (e.g. Jemmy for Swing component library). This way of testing is slow and fragile: running hundreds or thousands of UI tests takes quite some time and changes to the user interface are likely to break the tests resulting in false negatives.

As a company specializing in RIA, we at Canoo have witnessed quite a few transitions from plain ugly Web applications to the brave new world of RIA. Some of our observations:

  • Typical Web developers have not heard of MVC and try to design RIAs like they would design a typical HTML application.

  • Seasoned developers who may have had some experience with fat client-server applications try to apply MVC concepts in the same way that they did in the nineties, without adapting to the new scenario.

Both approaches have their weaknesses and lead to poor results. In part two of this blog post series - “The world needs more models” - we will discuss possible remedies to this situation.

More Stories By Bruno Schaeffer

Bruno Schaeffer is Co-Founder & CTO of Canoo Technologies. Since 1997 he has been a Java developer, consultant, and architect. His areas of expertise are Web application platforms and Rich Internet Application technologies.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
The standardization of container runtimes and images has sparked the creation of an almost overwhelming number of new open source projects that build on and otherwise work with these specifications. Of course, there's Kubernetes, which orchestrates and manages collections of containers. It was one of the first and best-known examples of projects that make containers truly useful for production use. However, more recently, the container ecosystem has truly exploded. A service mesh like Istio addr...
SYS-CON Events announced today that DatacenterDynamics has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY. DatacenterDynamics is a brand of DCD Group, a global B2B media and publishing company that develops products to help senior professionals in the world's most ICT dependent organizations make risk-based infrastructure and capacity decisions.
Nicolas Fierro is CEO of MIMIR Blockchain Solutions. He is a programmer, technologist, and operations dev who has worked with Ethereum and blockchain since 2014. His knowledge in blockchain dates to when he performed dev ops services to the Ethereum Foundation as one the privileged few developers to work with the original core team in Switzerland.
Cloud-enabled transformation has evolved from cost saving measure to business innovation strategy -- one that combines the cloud with cognitive capabilities to drive market disruption. Learn how you can achieve the insight and agility you need to gain a competitive advantage. Industry-acclaimed CTO and cloud expert, Shankar Kalyana presents. Only the most exceptional IBMers are appointed with the rare distinction of IBM Fellow, the highest technical honor in the company. Shankar has also receive...
Headquartered in Plainsboro, NJ, Synametrics Technologies has provided IT professionals and computer systems developers since 1997. Based on the success of their initial product offerings (WinSQL and DeltaCopy), the company continues to create and hone innovative products that help its customers get more from their computer applications, databases and infrastructure. To date, over one million users around the world have chosen Synametrics solutions to help power their accelerated business or per...
DXWorldEXPO LLC announced today that ICOHOLDER named "Media Sponsor" of Miami Blockchain Event by FinTechEXPO. ICOHOLDER gives detailed information and help the community to invest in the trusty projects. Miami Blockchain Event by FinTechEXPO has opened its Call for Papers. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Miami Blockchain Event by FinTechEXPOalso offers sp...
Digital Transformation is much more than a buzzword. The radical shift to digital mechanisms for almost every process is evident across all industries and verticals. This is often especially true in financial services, where the legacy environment is many times unable to keep up with the rapidly shifting demands of the consumer. The constant pressure to provide complete, omnichannel delivery of customer-facing solutions to meet both regulatory and customer demands is putting enormous pressure on...
@DevOpsSummit at Cloud Expo, taking place November 12-13 in New York City, NY, is co-located with 22nd international CloudEXPO | first international DXWorldEXPO and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time t...
When talking IoT we often focus on the devices, the sensors, the hardware itself. The new smart appliances, the new smart or self-driving cars (which are amalgamations of many ‘things'). When we are looking at the world of IoT, we should take a step back, look at the big picture. What value are these devices providing. IoT is not about the devices, its about the data consumed and generated. The devices are tools, mechanisms, conduits. This paper discusses the considerations when dealing with the...
SYS-CON Events announced today that IoT Global Network has been named “Media Sponsor” of SYS-CON's @ThingsExpo, which will take place on June 6–8, 2017, at the Javits Center in New York City, NY. The IoT Global Network is a platform where you can connect with industry experts and network across the IoT community to build the successful IoT business of the future.