KDAB TV – Recent Videos KDAB's YouTube Channel: Qt, C++ and 3D tutorials, news and more

Adding Double Click to a QPushButton

The task was simple: Add double click to a push button - with the added bonus of it not emitting the normal clicked if there is a double click.

OK, this sounds trivial, right? Well no, it wasn't entirely. To get it right you have to understand quite a bit of both signals/slots and the event system.

0:00 Introduction
0:22 A push button emitting double click - without emitting single click
1:44 Part 1 - Override mouseDoubleClickEvent
2:41 Part 2 - Introducing the crystal ball (a QTimer to postpone the single click signal)
4:58 Part 3 - Ensure up state is painted, but that the super class doesn't emit the signal - using QSignalBlocker
6:05 Part 4 - Understanding why we get the late "Thanks"
10:23 Part 5 - Simply use a flag to block the false event
11:56 Wouldn't it have been easier to implement a new button from scratch?

The example code showcased in this video is available here: https://github.com/KDABLabs/kdabtv/tree/master/Qt-Widgets-and-more/double-click-push-button

All Qt Widgets and more videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6gf-G-o6syFwGrtq3kItEqI

About the host:
The video is presented by Jesper Pedersen, who started with Qt back when Qt was widgets only and the version was 1.44, which gives him 21 years of experience with Qt. Since 2000 he has taught almost 100 Qt classes, ranging from Qt Widgets to QML. Heck, Jesper even taught a few classes on QTopia Core — Trolltech's initial attempt at creating a phone stack. Today Jesper holds a fancy business title, but that doesn't prevent him from coding both in his job and in his spare time.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing and innovative software across embedded, mobile and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrolment courses around the world. We are the market leaders for training in Qt, OpenGL and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are over 100 people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK and the USA. https://www.kdab.com/about/contact/

8 0

Luma Vision's VERAFEYE - 4D Digital Imaging with Qt

LUMA Vision is developing cutting-edge 4D digital imaging (i.e. real time 3D rendering) and navigation to enhance cardiologists' and electrophysiologists' visibility into the heart during intracardiac procedures. With KDAB's support, they are creating it by using Qt to tap into top-notch graphics technology. Watch the video to learn more.

Luma Vision website https://lumavision.com/

All showcases videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hWTi9AEI1zSfbmC4Skmokb

About the host:
Christoph Hennersperger is passionate about medical device development. In 2017, he co-founded LumaVision (once known as OneProjects). This company mixes hardware, software, and data science to shape the future of healthcare. They aim to find better ways to treat patients using data-driven solutions.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

5 1

Show Me Your IDE: VSCode

In this last episode on "Show me your IDE", we now look at visual studio code.

0:00 Intro
0:47 Debugging on windows is faster than in Qt Creator
2:37 It is very nice and clean
3:00 Git management
5:02 The IDE overall is fast - esp wrt peek
7:03 Getting started you need plugins
8:56 Qt Creator is better than VSCode when it comes to Qt refactorings
10:47 Qt Designer
12:23 Why are refactorings missing?
14:42 VSCode on Linux and Mac?
15:31 Search and replace across lost of files - preserve case
18:02 So, you are switching to Visual Studio?

All Qt Widgets and more videos:
https://www.youtube.com/playlist?list=PL6CJYn40gN6gf-G-o6syFwGrtq3kItEqI

Links:
* VSCode Template for Qt: https://github.com/KDABLabs/blog-vscode-template

* Archive of a few different VSCode things from KDAB: https://www.kdab.com/category/blogs/visual-studio-code/

About the host:
The video is presented by Jesper Pedersen, who started with Qt back when Qt was widgets only and the version was 1.44, which gives him 21 years of experience with Qt. Since 2000 he has taught almost 100 Qt classes, ranging from Qt Widgets to QML. Heck, Jesper even taught a few classes on QTopia Core — Trolltech's initial attempt at creating a phone stack. Today Jesper holds a fancy business title, but that doesn't prevent him from coding both in his job and in his spare time.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing and innovative software across embedded, mobile and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrolment courses around the world. We are the market leaders for training in Qt, OpenGL and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are over 100 people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK and the USA. https://www.kdab.com/about/contact/

9 7

KDAB News 03/2024 - Servo with Qt; Qt 6.7; Hotspot 1.5; Embedded World Impressions; Oxidize and more

Welcome to KDAB News, the monthly update for developers working with Qt, C++ and 3D technologies.

In this edition, we have:

0:48 Servo for Qt - Interview with Andrew Hayzen and Magnus Groß
5:54 Qt 6.7 released
6:55 Hotspot 1.5 released
7:50 Embedded World 2024 Impressions
11:49 Tip of the month - ConnectionEvaluator in KDBindings
12:41 Announcements

**

Here you find all the links mentioned in the news:

Oxidize 2024
https://oxidizeconf.com/

Servo with Qt

Blog post:
https://www.kdab.com/embedding-servo-in-qt/

CXX-Qt Servo webview GitHub:
https://github.com/KDABLabs/cxx-qt-servo-webview

Qt 6.7 released
https://www.qt.io/blog/qt-6.7-released

Hotspot 1.5 released
https://www.kdab.com/hotspot-v1-5-0-released/

Embedded World 2024 impressions

KDAB at Embedded World 2024
https://www.youtube.com/playlist?list=PL6CJYn40gN6gkep9s1ldikEFNS4FTd4iv

KDAB at previous Embedded Worlds
https://www.youtube.com/playlist?list=PL6CJYn40gN6hdOVE4eSKnZ4vv7333xmDP

Toradex
https://www.toradex.com/

How to get early access to the i.MX 95 Verdin evaluation kit
https://www.toradex.com/computer-on-modules/verdin-arm-family/nxp-imx95-evaluation-kit

Embedded World 2025
https://www.embedded-world.de/de-de

Tip of the month - ConnectionEvaluator in KDBindings

Blog post
https://www.kdab.com/introducing-the-connectionevaluator-in-kdbindings/

KDBindings
https://github.com/KDAB/KDBindings

Announcements

Oxidize 2024
https://oxidizeconf.com/

KDE Akademy 2024
https://akademy.kde.org/2024/

Qt Contributor Summit 2024
https://www.qt.io/blog/qtcs24-sep-5-6-save-the-date

Meeting C++ 2024
https://meetingcpp.com/2024/

ISO C++ Meeting Conference 2024
https://isocpp.org/files/papers/N4974.pdf

RustLab 2024
https://rustlab.it/

About KDAB:

KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

16 0

GCompris in India - An Example of Its Global Spread, from a Contributor's Perspective.

In this video, we talk to Aiśwarya Kaitheri Kandoth (Aish) who tells us about the growth of free software in Kerala, India, and of her role in the take-up and evolution of GCompris in schools there.

Timestamps and sections' names:
00:43: Take-up of free software and GCompris in Kerala
02:34 Access to computers - how GCompris got rooted there
05:50 Access during the pandemic
07:09 Translating Malalayam and getting financial support
10:10 Contributing to GCompris for special needs
11:41 Getting the new version into schools
13:46 Maintaining the activities and keeping in touch with users
16:00 KDE Networks globally
16:43 How to contribute to GCompris

Links:
* Link to download GCompris: https://gcompris.net/downloads-en.html

* GCompris Part 1: https://www.youtube.com/watch?v=hGldNGDg56o

* GCompris Part 2: https://www.youtube.com/watch?v=UtDkiWjmUio

* KDE Network in Kerala India: https://timotheegiet.com/blog/floss/tales-of-the-kde-network-kerala.html

* KDE Season of KDE: https://mentorship.kde.org/sok/

* About GCompris: https://gcompris.net/index-en.html

* Get involved in KDE: https://community.kde.org/Get_Involved

* KDE for kids: https://kde.org/for/kids/

* Google Summer of Code: https://summerofcode.withgoogle.com/

All 'Insights' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6ge6LFm39z6QB_jUefkboa6

About the hosts:
Aiśwarya Kaitheri Kandoth (Aish) is an electronic engineer and a developer. She has been contributing code and Malayalam translations to GCompris since 2018. She also contributes to several other Free Software projects. Aish now lives in France with her husband, Timothée, and their child.

Frances Tait works for KDAB since 2012 when she was hired to help make the Qt Developer Days event happen. Since then she has worked on multiple marketing tasks including creating customer showcases and taking care of KDAB's partners and collaborators.

More about GCompris:
GCompris is a free and open source, high quality, educational software suite for kids aged 2 – 10, that’s built with Qt.

It was originally written in C and Python using the GTK+ widget toolkit, but a rewrite in C++ and QML using the Qt widget toolkit was initiated by Bruno Coudoin in 2014.

GCompris is used as a teaching aid worldwide. It is available in multiple languages and has global users estimated to be in the millions. With its multiple datasets, GCompris Activities can be adjusted to fit pupil’s learning needs, and fitted into their existing lesson plans, individually or in groups.

Aside from its benefit as an addition to any teaching curriculum, GCompris is proven to be especially helpful for children with learning difficulties or neurological differences. Its content is non violent, quieter, and free from distractions like pop-ups or advertisements. It has also been designed to be non-addictive. https://gcompris.net/index-en.html

These days, GCompris is a project under the umbrella of KDE, a long-term partner of KDAB.

* GCompris Contributor’s site wiki: https://gcompris.net/wiki/New_contributor

* Patreon donation site for GCompris: https://gcompris.net/donate-en.html

* GTK: https://www.gtk.org/

* Gnome: https://www.gnome.org/get-involved/

* Python: https://www.python.org/

* Google Summer of Code: https://summerofcode.withgoogle.com/

About KDE:
KDE is an international community supporting the cooperative development and distribution of Free, Open Source Software for desktop and portable computing: https://kde.org/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more: https://www.kdab.com/software-services

Keep in touch with KDAB developments by signing up for our monthly newsletter featuring news and technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are about 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

7 3

Deploy: Faster!

When developing for embedded devices, turnaround times are often long and slow down the development experience. Complex multi-step processes are not rare, when deploying a mature multi-executable application to an embedded target.

In the first part I show a quick template script that you can use to swiftly deploy multi-app setups to your target. In a the longer, second part, Qt-Creator target configurations are explained in a tutorial. Last, I show how nightlies helped not only for development, but post-hoc debugging.

Links:
* Documentation for SSH Configurations: https://linux.die.net/man/5/ssh_config

* Blog: Crosscompile SDKs on Qt-Creator by Burkhard Stubert: https://embeddeduse.com/2020/11/21/cross-compiling-qt-embedded-applications-with-qtcreator-and-cmake/

All 'Reducing your Qt Embedded development cycle time' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6gUTZ9kAW7ocyjIVe5QbOUB

All 'Embedded with Qt' videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6iVG059HBoLQZ1CMTyXCGpw

About the host:
Christoph has been developing with C++ for over 15 years, and Qt for the last 8. A contributor to Gammaray, KDAB’s in-depth Qt-Analysis-Tool, Christoph specializes in performance optimization for embedded systems.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

9 0

Kistler's Handheld Qt Device Shows Data from Piezoelectric Sensors

In this video, Christoph demonstrates a hammer and feather demo utilizing Kistler's highly sensitive sensors to measure force. Kistler, a Swiss company, specializes in crafting top-tier piezoelectric sensors for measuring industry-specific physical parameters like force, acceleration, pressure and mechanical strain.

To examine intricate machinery equipped with these sensors internally, Kistler has engineered a handheld measurement device running Linux and a Qt application on top. This allows engineers and technicians to comprehend, assess, and configure those high-precision sensors without disassembling the machinery.

Links:
* Kistler: https://www.kistler.com/INT/en/

All "KDAB at Embedded World" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hdOVE4eSKnZ4vv7333xmDP

All "Embedded World 2024" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6gkep9s1ldikEFNS4FTd4iv

About the host:
Christoph has been developing with C++ for over 15 years, and Qt for the last 8. A contributor to Gammaray, KDAB’s in-depth Qt-Analysis-Tool, Christoph specializes in performance optimization for embedded systems.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

8 0

Touch-based Electric Vehicle Charger Interface

Simon Hausmann from Slint talks about how KDAB and tQCS revamped the user interface of SK Signet's top electric vehicle charger. This app plays video ads while the car charges. Video playback is handled by FFmpeg, and networking is managed with Curl. The product comes in 15-inch and 32-inch screen options with dynamic dark/light mode.

Links: 
* Blog: https://slint.dev/blog/beyond-ui-using-slint-with-cpp
* Slint: https://slint.dev/
* The Qt Company: https://www.tqcs.io/
* SK Signet: https://sksignet.us/

All "KDAB at Embedded World" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hdOVE4eSKnZ4vv7333xmDP

All "Embedded World 2024" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6gkep9s1ldikEFNS4FTd4iv

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more.  https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

13 1

Choose Rust to Speed up and Secure Online Content Display in Your Qt App

You may have already faced the challenge of showing website content within your Qt application. However, Qt doesn't excel in this - it's often slow and securely connecting to external web sources is also a valid concern. Watch this video to discover how seamlessly integrating Rust into your Qt application logic can address these issues and enhance performance.

If you're interested in learning more about combining C++ and Rust, check out our whitepaper: https://www.kdab.com/publications/bestpractices/best-practices-hybrid-rust-cpp-apps.html#building-hybrid-rust-and-c-c-applications

Links:
* Blog: https://www.kdab.com/embedding-servo-in-qt/
* CXX-Qt with servo Github: https://github.com/KDABLabs/cxx-qt-servo-webview
* CXX-Qt Github Repository: https://github.com/KDAB/cxx-qt/

All "KDAB at Embedded World" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hdOVE4eSKnZ4vv7333xmDP

All "Embedded World 2024" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6gkep9s1ldikEFNS4FTd4iv

About the host:
Andrew Hayzen is a Senior Software Engineer at KDAB and a Rust enthusiast. He has co-authored the development of CXX-Qt.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

13 1

Choosing Hardware for Your First Embedded Linux Device

As a consulting company, we've gotten to work on lots of different circuit boards and computer chips. In this video you'll see some examples and Christoph will point out what makes each one special. If you want to learn more about choosing the right hardware for your project, you can check out our independent whitepaper: https://www.kdab.com/publications/bestpractices/best-practices-embedded.html#embedded-development

All "KDAB at Embedded World" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6hdOVE4eSKnZ4vv7333xmDP

All "Embedded World 2024" videos: https://www.youtube.com/playlist?list=PL6CJYn40gN6gkep9s1ldikEFNS4FTd4iv

About the host:
Christoph has been developing with C++ for over 15 years, and Qt for the last 8. A contributor to Gammaray, KDAB’s in-depth Qt-Analysis-Tool, Christoph specializes in performance optimization for embedded systems.

Every month our newsletter is featuring technical blogs on Qt, C++ and 3D topics: https://www.kdab.com/development-resources/sign-up-for-our-newsletter/

About KDAB:
KDAB offers experienced software experts to help you deliver functional, high-performing, and innovative software across embedded, mobile, and desktop platforms for projects using C++, Qt, QML/Qt Quick, OpenGL, Qt 3D, and more. https://www.kdab.com/software-services

KDAB experts regularly take time out to deliver KDAB’s world class training, in-house or at open enrollment courses around the world. We are the market leaders for training in Qt, OpenGL, and C++.

Contact us to find out more at training@kdab.com or visit our website: https://www.kdab.com/software-services/scheduled-training/

We are 100+ people, located all around the world. Our Head Office is in Sweden and we have other offices in Germany, France, the UK, and the USA. https://www.kdab.com/about/contact/

14 0