Flutter Design Patterns: 6 — State

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

Previously in the series, I have analysed one of the most practical design patterns you can use in day-to-day coding — Strategy. In this article, I will analyse and implement a pattern, which has a similar structure to Strategy but is used for a different purpose — the State design pattern.

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Table of Contents

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

What is the State design pattern?

The State is a behavioural design pattern, which intention in the GoF book is described like this:

Allow an object to alter its behaviour when its internal state changes. The object will appear to change its class.