Composition vs Inheritance in UI

Introduction

In modern UI frameworks, developers often face the choice between composition and inheritance when designing their UI components. Understanding the differences and appropriate use cases for each can significantly affect the maintainability and scalability of an application.

Definitions

Composition

Composition is often favored in modern UI frameworks for the following reasons:

• Promotes reusability of components.
• Encourages separation of concerns.
• Improves flexibility in component design.

Code Example of Composition

function Button({ label, onClick }) {
    return <button onClick={onClick}>{label}</button>;
}

function App() {
    return (
        <div>
            <Button label="Click Me" onClick={() => alert('Button Clicked!')} />
        </div>
    );
}
        

Inheritance

Inheritance can lead to problems such as tight coupling and rigid hierarchies. However, it may still be useful in certain scenarios:

• Useful for sharing common behavior and state.
• Can simplify the extension of existing components.

Code Example of Inheritance

class Button {
    constructor(label) {
        this.label = label;
    }
    render() {
        return <button>{this.label}</button>;
    }
}

class IconButton extends Button {
    constructor(label, icon) {
        super(label);
        this.icon = icon;
    }
    render() {
        return <button><img src={this.icon} /> {this.label}</button>;
    }
}
        

Comparison

Here is a quick comparison of both approaches:

Best Practices

When deciding between composition and inheritance, consider the following best practices:

• Favor composition over inheritance for building UI components.
• Use inheritance only when necessary and understand the implications.
• Maintain clear documentation to help other developers understand your design choices.

FAQ