Flutter Design Patterns: 16 — Decorator

An overview of the Decorator design pattern and its implementation in Dart and Flutter

Previously in the series, I have analysed a relatively simple, but very practical design pattern — Proxy. This time I would like to represent a design pattern, that, unlike the Strategy design pattern, extends the functionality of an object instead of exchanging it. It is a structural design pattern called Decorator.

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Table of Contents

• What is the Decorator design pattern?
• Analysis
• Implementation
• Other articles in this series
• Your contribution

What is the Decorator design pattern?

When you see a separate class created for every possible combination of components (source)

Decorator, also known as Wrapper, is a structural design pattern, which intention in the GoF book is described like this: