We all know that software architecture in the software industry is an important and paramount issue. It is very important to design the code so that each piece is easily identifiable for the specific purpose and fits perfectly with the other pieces in a logical way. And it must be easy to maintain, scalable and have great quality. When developing an iOS app, it is important to keep in mind that iOS architecture should be used. The vast majority of developers use the so-called MVC (Model-View-Controller) architecture pattern suggested by Apple. But there are many more alternate patterns to develop iOS architecture! In this article, we will take a look at the VIPER architecture, one of the most common alternatives to MVC today that can help you overcome the limitations while having a well-organized code, improving your development system.

What is the VIPER architecture?

VIPER is an acronym for View, Interactor, Presenter, Entity and Router. This architecture is based on Principles of Unique Responsibility, which guides towards a cleaner architecture in order to have a better structure of the iOS project.

Let’s see what each one of the parts of the VIPER means:

View

The responsibility of the hearing is to send the user’s actions when presenting and teaching what the presenter says.

Interactor

This is the backbone of the application since it contains the business logic described by the use cases in the application. The interactor is responsible for attracting data from the mode layer, and its implementation is completely independent of the user interface.

Presenter

Your responsibility is to take data from the interactor in user actions, create an example of a model seen and take it to the View to show it.

Entity

It contains the basic model of objects used by the interactor. It has part of responsibilities of the model layer in other architectures.

Router

It has all the navigation logic to describe what the screen wants to show and when.

In the VIPER architecture, each block corresponds to an object with specific tasks, inputs and outputs. It is very similar to workers in an online organization: once a worker completes his task on an object, it is passed on to the next worker in the row until the product is completed. The connections between the blocks represent the relationship between the objects and the type of information that is transmitted between them. The communication from one entity to another is transmitted through the protocols.

The idea behind VIPER architecture

The idea behind this architecture pattern is to separate the dependencies of your app, balancing the delegation of responsibilities among the entities. Basically, the Viper architecture divides your application logic into smaller layers of functionality each with a strict, with a predefined responsibility. This makes testing the interactions at the boundaries of the layers easier. It fits quite well with unit tests and makes your code reusable.

Key advantages of a VIPER architecture structure

• Simplify complex projects. As the modules are independent Viper works very well for large equipment.
• It makes it scalable. Enables developers to work simultaneously on it without problems.
• Decouple the code to re-use it and test it.
• Divide the components of the application according to their role
• Mark the responsibilities clearly. Viper is a champion in the distribution of his responsibilities.
• It facilitates the writing of automatic tests
• Ease to add new features. since the logic of UI is separated from the business logic.
• Separate problems to make it easier to adopt TDD. The interactor contains a pure logic independent of any UI, which makes it easy to carry out tests.
• VIPER architecture is easy to use.
• Create clearer and better-defined interfaces, independent of other modules. This makes it easier to change the way your interface presents several user modules.
• Ease to keep track of problems via crash reports due to the principles of unique responsibility.
• Makes the source code clearer, more compact and reusable.
• Reduce the number of conflicts within the development team.
• Applies the SOLID principles.
• Reduce the number of mixed conflicts.
• You can create a skeleton architecture initially and later give modules one by one to other developers to implement the logic.
• Makes the codebase look similar. What makes other people’s code read faster.

The Viper architecture has many benefits, but it is important to mention that it is better to use it in large, highly complex projects. Due to the number of elements involved, this architecture causes overhead when applied to small projects, so the Viper architecture can be an exaggerated measure for small projects that seek scalability. For this type of project, it is better to use another method, such as MVVM.

Using Viper architecture in your existing app

We are talking about the possibility of using Viper architecture in your existing app. In this case, consider adding a new feature with Viper. This allows you to build a module using Viper’s architecture and also helps you find problems that make it more complex to adopt an architecture based on the principles of unique responsibility.

The VIPER architecture is a good solution to build software that develops for iOS applications to be proud! If you have any questions, leave them in the comments section below!