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Moyeen Haider
Moyeen Haider

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The Open/Closed Principle (OCP): A Balance of Extensibility 🎻

🌟 Introduction:
Greetings, fellow developers! Today, we dive further into the attractive domain of SOLID principles, setting our sights on the second star: the Open/Closed Principle (OCP). πŸš€ Imagine a codebase that welcomes change without breaking existing functionality β€” that’s the magic OCP brings to our Flutter development journey.

πŸ”„ Unleashing the Power of OCP:

Why OCP? 🌌
In the ever-evolving world of software development, change is the only constant. OCP empowers us to extend our codebase without modifying existing, working code. Think of OCP as the guardian of your code, ensuring it’s open to new features but closed to unnecessary alterations.

What is OCP? πŸ”
At its core, OCP encourages us to design software entities that are open for extension but closed for modification. Picture your code as a treasure chest, where adding new gems (features) doesn’t require rearranging the existing treasures (code).

How OCP Transforms Our Codebase: πŸ§™β€β™‚οΈ
Let’s take a look in a Dart code example to witness OCP in action:

// Incorrect Approach
class Shape {
  // Violates OCP by using a single method for calculating the area of different shapes.
  double calculateArea(dynamic shape) {
    if (shape is Circle) {
      return 3.14 * shape.radius * shape.radius;
    } else if (shape is Square) {
      return shape.side * shape.side;

// Corrected Approach
abstract class Shape {
  double area();

class Circle implements Shape {
  // Implementation for calculating the area of a circle.

class Square implements Shape {
  // Implementation for calculating the area of a square.

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🚨 Why it Was Wrong:

The initial approach violated OCP by using a single method for calculating the area of different shapes, requiring modification for each new shape.

✨ What We Should Do Instead:

The corrected approach introduces an abstract Shape class and allows each shape to implement its own area method, conforming to OCP.

🌈 Reasons Behind the Approach:

By embracing abstraction, the code becomes open for extension. Adding new shapes is as simple as creating a new class that implements the Shape interface. OCP transforms our codebase into a flexible, extensible masterpiece.

🎭 Conclusion:
As we good-bye to the exploration of OCP, visualize your code as an ever-expanding canvas ready to accepet new features. OCP covers the way for a codebase that evolves gracefully, adapting to the changing needs of your Flutter or any other project. Stay tuned for our next SOLID principality: the Liskov Substitution Principle! πŸš€πŸ’»

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