In the last article, I have analysed a behavioural design pattern which enables loose coupling between the sender of a request and its receiver — 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.

Table of Contents

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

What is the Visitor design pattern?

Previously in the series, I have analysed a structural design pattern that introduced a concept of a “shared object” which could be used in multiple contexts simultaneously, hence reducing the memory usage of your code — Flyweight. This time I would like to represent a behavioural design pattern, which enables loose coupling between the sender of a request and its receiver, also adding a possibility for the same request to be handled by multiple handlers — it is the Chain of Responsibility.

Table of Contents

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

What is the Chain of Responsibility design pattern?

In the last article, I have analysed a creational design pattern which divides the construction of a complex object into several separate steps — Builder. In this article, I would like to analyse and implement a structural design pattern that helps using a huge number of objects in your code which could barely fit into available RAM — it is Flyweight.

Table of Contents

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

What is the Flyweight design pattern?

When I started my journey in the Flutter world, I have learned the basic UI concepts just enough to build a simple application. State management, code structure, architecture, appliance of OOP design patterns — these topics are more interesting to me, so I have dived deeper into them. However, the majority of developers choose Flutter for its UI capabilities.

There are lots and lots of tutorials, articles out there on how to make custom UIs, applications using Dart + Flutter, but the majority of them covers only the HOW part (how to implement a specific component, animation, etc.), but usually the WHY part (why is it implemented in a certain way) is left somewhere else. This article covers the whole thought process on how to convert the design into code: explains HOW to do it and WHY it is done like this. …

Previously in the series, I have analysed a relatively complex, but very practical and useful structural design pattern — Bridge. This time I would like to represent a design pattern, which divides the construction of a complex object into several separate steps. It is a creational design pattern called Builder.

Table of Contents

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

What is the Builder design pattern?

In the last article, I have analysed a structural design pattern which provides a way of changing the skin of an object without changing its guts — Decorator. In this article, I would like to analyse and implement another structural design pattern that tends to be relatively difficult to understand compared to the other design patterns, but at the same time is practical and useful — it is Bridge.

Table of Contents

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

What is the Bridge design pattern?

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, which, unlike the Strategy design pattern, extends the functionality of an object instead of exchanging it. It is a structural design pattern called Decorator.

Table of Contents

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

What is the Decorator design pattern?

In the last article, I have analysed a relatively simple design pattern comparing to the other patterns in the series — Prototype. In this article, I would like to analyse and implement a structural design pattern which is very practical and could be used in a lot of cases when developing applications with Dart and Flutter — it is Proxy.

Table of Contents

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

What is the Proxy design pattern?