No matter how elegant, complex, and crisp the code is, the end-users are never going to interact with it, and they are going to interact with what these codes accomplish. They interact with links, images, buttons, lists, etc. They base their experience of software or an app by the number of clicks it takes them to accomplish a task, navigation, and easy-of-use. This makes the UI architectural patterns of utmost importance.
The three most commonly used UI architectural patterns are MVC, MVP, and MVVM. Both MVP and MVVM are derived from MVC. The main difference between the derivatives of MVC and MVC itself is the dependency each layer has on other layers.
All of these architectural UI patterns play an important role in providing proven solutions to end-users frequent problems, saving the creating and testing time of developers, and catalyzing the overall development process.
These architectural UI design patterns are present everywhere on sites and apps and are instinctively familiar to the end-users. It will not even take seconds for a user to understand what needs to be done within an interface designed with common UI design patterns. Adopting common patterns means you can leverage this knowledge and increase the end-user experience of the product.
Let us get into the nitty-gritty of these three common UI architectural patterns:
(i) MVC Pattern
MVC or Model View Controller is the earliest architectural pattern specifically designed for web and application in the 1970s. MVC allows you to create applications and software with SoC (separation of concern), which in return eases the efforts to test, maintain, and update an application. It is known that in the traditional software development procedure, a relevant code is written is user control is used to make the view part of the defined class. Furthermore, this procedure increases the size of binding logic, user interface, and the size of the view class among business operations. The MVC architectural pattern is designed to reduce the code size as well as make it neat, to easily manage it.
Let us discuss the layers in detail:
This is the central component of the system; it is also the dynamic data structure and is independent of the UI. It manages the rules of the application with data and logic.
Any representation of information in the form of a chart, diagram, or table. Multiple views of the same information are possible, for instance, a bar chart for management and a tabular view for accountants.
Accepts input and converts it to commands for the Model or the View.
In MVC, the View sits on top of architecture with the Controller next to it. The Controller is very responsive to the incoming requests. It sends the user’s data through the Model to the View. Thus, it acts as a facilitator between the Model and the View.
In this pattern, the Models sit below the Controller, so the Views know about the Controllers, and the Controllers know about the Models. Here, the Views have direct access to the Models. It is to be noted that exposing the complete Model to the View may have security and performance costs depending on the complexity of an application. MVVM attempts to avoid these issues, which we will discuss later in this article.
(ii) The MVP Pattern
There are many similarities between the MVP pattern and the MVC pattern. The letter P in this architectural UI pattern stands for the word Presenter. The Controller is replaced with the Presenter here. Presenters sit at the same level as the Views, listening to events from both the View and the Model, and regulating the actions between the two. In this pattern, we rely on each View, implementing an interface letting the Presenter interact with the View.
Thus, the Presenter is responsible for addressing all the events on behalf of the View. It gets input from the users then sends the data to the Model that then transforms the result back to the View.
MVP is an architectural user interface pattern designed to provide automated unit testing of software and to improve the separation of concerns (SoC) in presentation logic.
Let us understand the layers:
The Model is a user interface that defines the data that has to be displayed or else acted upon in the user interface.
The View is a passive interface that not only displays the data but also routes user commands, also known as events to the Presenter to act upon that data.
The Presenter acts upon the Model as well as the View, it also retrieves data from the Model, and then formats it for display in the View.
From a layering POV, the presenter class can be considered to belong in a multi-layered architecture system, which can also be seen as a presenter layer in the middle of the application layer and the UI layer.
MVVM allows us to create View-specific subsets of a Model, which can contain logic information and state, removing the need to expose the entire Model to a View. Unlike MVP’s Presenter, referencing a View is not necessary by a ViewModel. The Viewcan bind to properties on the ViewModel, which will then expose data contained in the Models to the View. As we have mentioned above, the abstraction of the View asks for less logic required in the code behind it.
Let us understand the three layers:
It refers either to a domain model that represents a real state content or to the data access layer representing the content.
As in the MVC and MVP patterns, View is the layout, appearance, and structure of what a user sees on the screen. It receives the user’s interaction by the View (clicks, keyboard, gestures, etc.), and then forwards the handling of these to the view model through the data binding (properties, event callbacks, etc.) that is purposed to link the View and the view model.
The view model is an abstraction of the View, exposing commands and public properties. Just as the Controller of the MVC pattern, or the Presenter of the MVP pattern, MVVM has a binder.
Binder automates communication between the View and its bound properties in the view model. Command-binding and declarative data are implicit in the MVVM pattern. The binder frees the developer from being obliged to write boiler-plate logic to synchronize the view model and View.
We hope this article has been insightful. It’s important to note that iOS, Android, and Ruby Rails use the MVC pattern, whereas ASP.NET web form applications use MVP. MVVM is used by Silverlight, nRoute, Caliburn, WPF, and more.
Paul Osborne is Serving as Chief Technical Officer at Cerdonis Technologies LLC – ASP.Net MVC development company in USA. A company with a team of developers with years of experience in building a cost-effective and user-friendly ASP.Net MVC Website and Application. As Technical Background I like to read & share my thoughts on Web & App Development