What should be the communication between Model and View using MVC?

Question

I’m trying to implement some small projects using the MVC standard: Within the project structure, I created the following packages:

• View : User Interaction Screens.
• Controller: I have a class with methods referring to user requests, save, change, delete, list.
• Modal: Class that implements the Serializable method.

As the application is with Sqlite local database integration, it has two more packages:

• Datamodal: Contains the project data model.
• Datasource: Contains the data source, in which the database is created, in this same class I have the data persistence method. Save, delete and list.

From what I understand, the controller does not communicate with Datasource, such communication is between Datasource and Model. Should the methods of inserting, updating, removing and listing the records be created in a separate class in Modal? How would the communication between the same and the Controller, and how the Modal return the information to the View: passing directly, or should pass to the Controller and the Controller provide this information to View?

Answer 1

Come on.

The methods of inserting, updating, removing and listing the records, must be created in a separate class in Modal?

This will depend on your architecture, you can "decouple" that part by creating a part of the system that does the CRUD and provide the Model with the data and then it passes this data to the Controllers. Behold DDD.

How would the communication between the same and the Controller, and how the Modal return the information to the View: passing directly, or should pass to the Controller and the Controller provide this information to View?

• How would the communication between the same and the Controller

  To use a Model in the Controller , you can instantiate the class of Model and access their respective methods.

• and how Modal returns the information to the View

When you create a Controller you associate a View to him, and so you have access to her elements, being able to control them, the Model is unaware of the Views is the Controller who makes this "bridge" between them.

I suggest you take a look at this post MVC and this article MVC

Answer 2

"From what I understand, the controller does not communicate with Datasource"

The control class, which is nothing more and nothing less than Activity, has to communicate with the class that inserts/delete/modifies the data.

To clarify my thinking: View = XML; Controller = Activity; Model = Entities (bank);

Your database will have a class that creates it. You can create another class that manages the database to facilitate data entry. Activity throws the data in this manager class it receives from the view (actually the data will already be in Activity itself, since xml is an "illusion")