Book Image

Mastering Delphi Programming: A Complete Reference Guide

By : Primož Gabrijelčič
Book Image

Mastering Delphi Programming: A Complete Reference Guide

By: Primož Gabrijelčič

Overview of this book

Delphi is a cross-platform Integrated Development Environment (IDE) that supports rapid application development for most operating systems, including Microsoft Windows, iOS, and now Linux with RAD Studio 10.2. If you know how to use the features of Delphi, you can easily create scalable applications in no time. This Learning Path begins by explaining how to find performance bottlenecks and apply the correct algorithm to fix them. You'll brush up on tricks, techniques, and best practices to solve common design and architectural challenges. Then, you'll see how to leverage external libraries to write better-performing programs. You'll also learn about the eight most important patterns that'll enable you to develop and improve the interface between items and harmonize shared memories within threads. As you progress, you'll also delve into improving the performance of your code and mastering cross-platform RTL improvements. By the end of this Learning Path, you'll be able to address common design problems and feel confident while building scalable projects. This Learning Path includes content from the following Packt products: Delphi High Performance by Primož Gabrijel?i? Hands-On Design Patterns with Delphi by Primož Gabrijel?i?
Table of Contents (19 chapters)

Visitor

The iterator pattern shows us how to separate the internal structure of a data container from the code that operates on it. A visitor pattern is similar in topic, but applies not so much to composite data as to composite objects. It shows how to implement an algorithm/object separation, which allows us to add new operations to existing objects without modifying their structure. As such, it represents a good example of the Open/Closed principle in practice.

In classical object-oriented code, a part of code (an algorithm) would take an object, inspect its internal structure, and operate on its parts. If we use the visitor pattern, this approach is turned on its head. The algorithm merely passes a method to the object and kindly asks it to execute that method on its constituent parts.

After you enter a city sightseeing bus, you have no longer control over your transportation...