Book Image

Delphi GUI Programming with FireMonkey

By : Andrea Magni
4 (1)
Book Image

Delphi GUI Programming with FireMonkey

4 (1)
By: Andrea Magni

Overview of this book

FireMonkey (FMX) is a cross-platform application framework that allows developers to create exciting user interfaces and deliver applications on multiple operating systems (OS). This book will help you learn visual programming with Delphi and FMX. Starting with an overview of the FMX framework, including a general discussion of the underlying philosophy and approach, you’ll then move on to the fundamentals and architectural details of FMX. You’ll also cover a significant comparison between Delphi and the Visual Component Library (VCL). Next, you’ll focus on the main FMX components, data access/data binding, and style concepts, in addition to understanding how to deliver visually responsive UIs. To address modern application development, the book takes you through topics such as animations and effects, and provides you with a general introduction to parallel programming, specifically targeting UI-related aspects, including application responsiveness. Later, you’ll explore the most important cross-platform services in the FMX framework, which are essential for delivering your application on multiple platforms while retaining the single codebase approach. Finally, you’ll learn about FMX’s built-in 3D functionalities. By the end of this book, you’ll be familiar with the FMX framework and be able to build effective cross-platform apps.
Table of Contents (18 chapters)
Section 1: Delphi GUI Programming Frameworks
Section 2: The FMX Framework in Depth
Section 3: Pushing to The Top: Advanced Topics

Scanning for devices

To scan for devices in the BLE range, you can call the DiscoverDevices method of the TBluetoothLE component:

      BLE1.DiscoverDevices(3000, [SERVICE_UUID]);

From the preceding code, the first argument represents the timeout for the discovery, in milliseconds. The second (optional) argument is a list of UUID identifiers. When the second argument is provided, it acts as a filter over devices in the range. GATT specification states each service and characteristic exposed through BLE has a unique identifier (UUID) so it is easy to discover all devices matching at least one of the listed service UUIDs. The following screenshot shows the Object Inspector pane listing TBluetoothLE events:

Figure 12.15 

Most of the functionalities around BLE are asynchronous so there are a number of events exposed by the component you'll need to handle. For example, once the device discovery has been started (using the previous line of code), you may want...