MVC, controller - use cases

Question

I\'ve learned that you should set up the controller-class in a MVC-OOD as a use case, from top to bottom in only one method that run the MVC-classes.

Is it OK to use

Answer 1

Its important to remember two things with MVC, firstly, its an Object-Oriented Architecture, and secondly, It should be used for separating concerns.

Separation of Concerns is related to Abstraction, It is to aid us in understanding the section of code at hand. The Model and View are both collections/domains of related objects. Each object is fully complete and relevant to its domain.

You will find objects with types such as Buttons, Images, Text Inputs etc inside your View, and you will find business related objects (User, Account, Profile etc) within your Model.

The collection of objects inside your Model don't tend to do much, They require logic to wire the objects together. (Or simply delegate simple single object requests to the correct object)

The Controller provides the interface into your Model, and contains the business logic related to the Model and the interactions between the Model objects. You will have a single Controller for your Model, and the Controller will have multiple methods which will align with your use-cases.

Answer 2

_{TL;DR -- you have misunderstood the MVC design pattern and are doing it wrong.}

Controllers are not responsible for rendering the interface, nor for presentation logic. Controllers do not display anything. Instead, each controller's method deals with different user's request. It extracts the data from said request and passes it to model layer and the associated view.

Decisions about what and how to display are in purview of views. Views contain the presentation logic in MVC pattern. In the context of web applications, views create the response. They can compose a from from multiple templates or just send a single HTTP header.

Controllers can signal the associated view by passing some specific values of the request to that view, but most of the decisions in the view are based on information that the view requested from different services in the model layer.

A Controller's methods are based on what type of requests a user can send. For example in a authentication form it might be: GET /login and/or POST /login.