Mvc pattern on Android

android

mvvm

view-binding

data-binding

byAnton Shumikhin·Oct 14, 2024

MVC in Android is a division of responsibility between Model (data), View (UI), and Controller (application logic). You can use Activities or Fragments as Controllers to pass information between Model and View. Here's a simple MVC example:

// Model: Holds data, like a silent film star - seen, not heard
public class User {
    // ... Other data and logic too complex for mortals
    public void setName(String name) { this.name = name; }
    public String getName() { return name; }
}

// View: Just pretty faces for UI updates
public interface UserView {
    void showUserName(String name);
}

// Controller: The divine chessmaster of Model and View
public class UserController {
    // ... Model, view, and divine logic
    public void updateUserName(String newName) {
        user.setName(newName);
        view.showUserName(newName);
    }
}

// UserActivity is the view in this celestial game

Always separate concerns, let Controllers manage the Model and View, and ensure that UI receives instant updates on data changes. This promises cleaner and more maintainable Android applications.

MVC architecture, sliced and served

To grasp the meat-and-potatoes of MVC architecture in Android, let's dissect its layers and how they operate in harmony.

Cut the clutter

In MVC, a differentiation of jobs is vital. A proper distribution of responsibilities enables:

Modularity: Alter or replace parts without breaking a sweat.
Testability: Test layers in isolation; no cross-contamination.
Maintainability: Understand and update the structure with ease.

The Matrix of user interface

For the View component, Android uses XML files to define UI layouts. The system "inflates" these XML files into view objects, maintaining the separation necessary for MVC.

Life's a stage for Controllers

Activities and Fragments in Android perform as Controllers and need to mind the lifecycle. They need to catch user events, manage the lifecycle, and take a bow when the system drops the curtain.

Platform independence for Models

The Model within MVC should turn a blind eye to the platform to allow easy sharing or migration across different platforms, easing cross-platform development.

What lurks behind the scenes

Exploring the crevices of MVC in Android reveals its intricacies and resolving them unlocks mastery over this design pattern.

The life and times of MVC and Android

Android employs certain lifecycle methods in Activities. Controllers need to play in harmony with these lifecycle methods, adding a layer of complexity to the otherwise straightforward controller.

Alternatives hidden in plain sight

MVVM (Model-View-ViewModel) could sometimes prove to be a smooth operator with Android's data-binding capabilities. This doesn't make MVC obsolete but deserves consideration when aligning with specific needs.

Cross the platform with MVC

Mono enables sharing Models across platforms, thus ensuring consistency and saving redundant effort. So, pack up that Model and see the world!

No sour code: Best practices

Choosing MVC is the first step. Sticking to best practices ensures the journey is smoother.

Draw clear lines: Establish explicit interfaces between Model, View, and Controller.
Keep Activities lean: Delegate logic-heavy tasks to specific classes.
Dance with the lifecycle: Handle system events within the Controller.
Cut Android dependencies: This aids the Model's portability.

Stay faithful to MVC

Maintaining the sanctity of MVC requires meticulous navigation of UI rendering and data logic

XML layouts: Should only lay down the UI structure, no heavy lifting.
View binding: Use Android's View Binding or Data Binding to attach UI components to data sources with minimum code in the Activity.

explain-codes / Android / Mvc pattern on Android

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