Book Image

Mastering Qt 5 - Second Edition

By : Guillaume Lazar, Robin Penea
Book Image

Mastering Qt 5 - Second Edition

By: Guillaume Lazar, Robin Penea

Overview of this book

Qt 5.11 is an app development framework that provides a great user experience and develops full capability applications with Qt Widgets, QML, and even Qt 3D. Whether you're building GUI prototypes or fully-fledged cross-platform GUI applications with a native look and feel, Mastering Qt 5 is your fastest, easiest, and most powerful solution. This book addresses various challenges and teaches you to successfully develop cross-platform applications using the Qt framework, with the help of well-organized projects. Working through this book, you will gain a better understanding of the Qt framework, as well as the tools required to resolve serious issues, such as linking, debugging, and multithreading. You'll start off your journey by discovering the new Qt 5.11 features, soon followed by exploring different platforms and learning to tame them. In addition to this, you'll interact with a gamepad using Qt Gamepad. Each chapter is a logical step for you to complete in order to master Qt. By the end of this book, you'll have created an application that has been tested and is ready to be shipped.
Table of Contents (16 chapters)

Qt Designer interface

Qt Designer is a major tool for developing Qt applications. This WYSIWYG editor will help you to easily design your GUI. If you switch between Edit mode and Design mode for the MainWindow.ui file, you will see the real XML content and the designer:

The designer displays several parts:

  • Form Editor (1): A visual representation of the form (empty for now)
  • Widget Box (2): Contains all the major widgets that can be used with your form
  • Object Inspector (3): Displays your form as a hierarchical tree
  • Property Editor (4): Enumerates the properties of the selected widget
  • Action Editor/Signal & Slots Editor (5): Handles toolbar actions and connections between your objects

It's time to embellish this empty window! Let's drag and drop a Label widget from the Display Widgets section on the form. You can change the name and the text properties directly from the Properties editor.

As we are making a todo application, we suggest these properties:

  • objectName: statusLabel
  • text: Status: 0 todo / 0 done

This label will later display the count of todo tasks and the count of tasks already done. Save, build, and start your application. You should now see your new label in the window.

You can now add a push button with those properties:

  • objectName: addTaskButton
  • text: Add task

You should get a result close to the following:

You can edit the text property of a widget directly on your form by double-clicking on it!

The design of the MainWindow.ui file is ready, we can now study the signals and slots.