Book Image

Hands-On Design Patterns with Delphi

By : Primož Gabrijelčič
Book Image

Hands-On Design Patterns with Delphi

By: Primož Gabrijelčič

Overview of this book

Design patterns have proven to be the go-to solution for many common programming scenarios. This book focuses on design patterns applied to the Delphi language. The book will provide you with insights into the language and its capabilities of a runtime library. You'll start by exploring a variety of design patterns and understanding them through real-world examples. This will entail a short explanation of the concept of design patterns and the original set of the 'Gang of Four' patterns, which will help you in structuring your designs efficiently. Next, you'll cover the most important 'anti-patterns' (essentially bad software development practices) to aid you in steering clear of problems during programming. You'll then learn about the eight most important patterns for each creational, structural, and behavioral type. After this, you'll be introduced to the concept of 'concurrency' patterns, which are design patterns specifically related to multithreading and parallel computation. These will enable you to develop and improve an interface between items and harmonize shared memories within threads. Toward the concluding chapters, you'll explore design patterns specific to program design and other categories of patterns that do not fall under the 'design' umbrella. By the end of this book, you'll be able to address common design problems encountered while developing applications and feel confident while building scalable projects.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Data modules


Data modules are another form-like container that we can find in Delphi. Like forms and frames, they are available both in VCL and FireMonkey frameworks. Unlike them, however, they don't accept controls, but only components. As such, they cannot be used to create graphical user interfaces. Nevertheless, they are excellent storage for datasets, SQL connections, and other non-visual components.

To create a new data module, select File | New | Other and then pick the Data Module icon in the Delphi Files branch. After pressing OK, Delphi will create a new unit and open the form designer. You will not be able to place controls on the design form, and the component palette will reflect this. While the data module is being edited, the component palette will not contain any controls, just non-visual components.

A data module can appear in three different types – VCL, FireMonkey, and framework-neutral. As you would assume, the VCL type is intended to be used with VCL applications, the...