Flutter Design Patterns: 21 — Visitor

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

In the last article, I analysed a behavioural design pattern that enables loose coupling between the sender of a request and its receiver — the Chain of Responsibility. In this article, I would like to analyse and implement another behavioural design pattern that lets you separate algorithms from the objects on which they operate — it is Visitor.

Update 2022–09–15: I moved this blog to my personal website. For a better reading experience, up to date articles, interactive code examples and some extra content FOR FREE, check kazlauskas.dev.

Table of Contents

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

What is the Visitor design pattern?

Class component with applied Visitor design pattern be like (source)

Visitor belongs to the category of behavioural design patterns. The intention of this design pattern is described in…