Model-View-Controller (MVC) is probably the most used architectural solution for User Interface design and web programming; Introduced first in the 70s, MVC has been progressively adapted and morphed into a wide range of subtypes and variations, so much that the plain term "MVC" without additional qualifications has lost specificity. As a general interpretation, it is a rather loose guideline for organizing your code when the data and visualization parts of your application need to interact while staying as loosely coupled as possible. How this is accomplished in practice depends on the particular MVC incarnation.
MVC can be seen as an aggregation of more fundamental design patterns such as Composite, Mediator and Observer/Notifier. The complexity and variation in style of MVC arises from all the possible uses and variations of these independent patterns to satisfy the potentially elaborate requirements of a GUI.
The objective of this book is to explore variations and nuances of MVC, comparing and analyzing them. The differentiating characteristic among them is to assign responsibilities to protagonists, specifically “who is responsible for what” and “who knows about whom” in the interaction between the User and the application state. MVC variations assign new and old responsibilities in different ways, connect or organize protagonists, or add intermediate objects to gain more flexibility and satisfy peculiar use cases.
The first chapter will introduce a simple ground-up MVC application through code, with the objective of deploying a common vocabulary. The chapter will define components, roles, and communication patterns, and close with a remark on how the resulting formulation is outdated and too simplistic in modern software development.
Throughout the book, example code or actual implementations will be presented to clarify design ideas. GUI rendering will make use of the excellent Qt toolkit. Qt provides pre-made mechanisms to address some MVC needs, but in the upcoming code these mechanisms will be skipped on purpose to demonstrate the presented concepts.
Acknowledgements and motivations
I started writing this book as an accident. Initially, I wanted to write a series of blog posts to describe Model View Controller and a few related patterns. As I gathered more and more information from the net and my personal experience, I suddenly found out that the amount and structure of what I wrote was beyond the scope of a blog, hence the decision to re-label it as a book. I am happy with the decision, because it gave me freedom to add material I would not have added otherwise.
This works presents and enriches design solutions, best practices, and experiments made available by countless blog posts and comments. To these authors goes my acknowledgement and gratitude. Being a work in progress, there's still a lot to be done. Please be patient, but feel free to send me feedback, pull requests, and take advantage of the material already present.
I already published a book with a commercial publisher, and from my experience and math, I think that if I put a book on the web and accept donations I would probably get more money and feedback than going through a publisher.
- on GratiPay
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- on PayPal (using my email address stefano.borini at ferrara dot linux dot it)
I also have a personal website at http://forthescience.org where you can find more information about me, my curriculum and activities.