Book Image

Expert Delphi

By : Paweł Głowacki
Book Image

Expert Delphi

By: Paweł Głowacki

Overview of this book

Delphi is the most powerful Object Pascal IDE and component library for cross-platform native app development. It enables building natively compiled, blazingly fast apps for all major platforms including Android, iOS, Windows, Mac, and Linux. If you want to build server-side applications, create web services, and have clear GUIs for your project, then this book is for you. The book begins with a basic primer on Delphi helping you get accustomed to the IDE and the Object Pascal language and will then quickly move on to advanced-level concepts. Through this book, we’ll help you understand the architecture of applications and will teach you the important concepts of the FireMonkey library, show you how to build server-side services, and enable you to interact with the Internet of Things. Towards the end, you will learn to integrate your app with various web services and deploy them. By the end of the book, you will be able to build powerful, cross-platform, native apps for iOS and Android with a single code base.
Table of Contents (14 chapters)

Get moving with timers

Let's take one further step, and, instead of having a static scene, let's add an animation. It is a normal thing for the sun to ascend in the morning. In order to achieve the effect of sunrise every time the form is repainted, we will change the y coordinate that is used for painting the sun's circle and rays. Let's add to our TFormSun class a private member FSunPosY: double, which will store the current vertical sun position.

The simplest way to change our scene over time is with the TTimer component. Drop TTimer on the form. It has only one event, OnTimer. The frequency of these events is controlled by the Interval property, which specifies the number of milliseconds between firing the OnTimer event. The default value of the Interval property is 1,000, which means that the timer fires its event every second. For a smooth animation,...