Solving cancer is probably the biggest mystery that we see unravel in our life. This is a complex one because cancer is not a single disease, there are a myriad of aspects that need to be uncovered. Qi (Quantitive Imaging Systems) images biopsies from patients and then labels individual cells with over a hundred biomarkers. […]

Clazy is a clang plugin which extends the compiler with over 50 warnings related to Qt best practices ranging from unneeded memory allocations to API misuse. It's an opensource project spawned by KDAB's R&D efforts for better C++ tooling. Today, we're proud to announce a Clazy Web UI to view all warnings emitted by Clazy, […]

When Competence Center ISOBUS (CCI) decided to bring their terminal up-to-date as part of the Group’s strategy to remain top of the field in advanced agritechnical innovation, they asked KDAB to help. The user interface in the operator’s cab displays multiple applications. It can control complex agricultural tools, receive and display complex reports and much […]

We have released version 2.8.1 of our Qt application introspection tool GammaRay. This release contains a number of important bugfixes as well as support for Qt 5.9.2. Especially if you are experiencing corrupt views or crashes when searching in the object tree, or having trouble attaching to a process on Windows, you want to upgrade […]

Sometimes data visualization might call for more than a graph - you need to visualize complex data, such as that generated by city lighting, in three dimensions to get the full effect. KDAB decided to put together a showcase for the Qt World Summit that allowed us to demonstrate Qt 3D's capabilities as a performant […]

QtQuick is a popular choice for creating HMIs for embedded devices. The hardware on these devices is often constrained and less performant than their desktop equivalents, this requires extra care from software developers in delivering a fluid user experience. KDAB is regularly involved in improving the performance of QtQuick HMIs on such devices for their […]

An existing code base can be a great asset, but it can also be a liability. Technical debt tends to build up over time, eventually reaching the point where something needs to be done. KDAB has unique experience in migrations as well as specialized tools and in-depth knowledge from migration projects in different industries with […]

Property bindings are one of the most interesting features of the QML language. In QML, when we set a value on a property, the right hand side expression isn't evaluated just once to produce a value, like in a ordinary imperative language. In particular, if the expression involves other properties, then the property we're setting […]

Introduction This article is part of a blog series about Clang Tidy. In the previous article we learned about the general usage of Clang Tidy to automatically refactor source code for projects using the CMake build system. In this particular episode we'll discuss using Clang Tooling on projects using different build systems with the help […]

In the previous episode we presented how to uncover 32 Qt best practices at compile time with clazy. Today it's time to show 5 more and other new goodies present in the freshly released clazy v1.2. New checks 1. connect-not-normalized Warns when the content of SIGNAL(), SLOT(), Q_ARG() and Q_RETURN_ARG() is not normalized. Using normalized […]

When using Qt's model/view framework, filtering has always been very easy with QSortFilterProxyModel. To filter a list using text typed by the user in a line-edit, you have certainly been applying the standard recipe: instantiate the proxy; insert it between view and source model; connect the lineedit's textChanged signal to the proxy's setFilterFixedString slot; done! […]

As my first subject for this animation blog series, we will be taking a look at Animation curves. Curves, or better, easing curves, is one of the first concepts we are exposed to when dealing with the subject of animation in the QML space. What are they? Well, in simplistic terms, they are a description […]

We have released version 2.8.0 of our Qt application introspection tool GammaRay. GammaRay allows you to observe behavior and data structures of Qt code inside your program live at runtime. A big focus in this release is improvements to the Qt Quick inspector, which gained layout helper grids and Qt Quick Controls 2 tracing, as […]

As there were some complex issues around conformity in PDF document creation within Qt, KDAB let me spend some time digging into it so we could make sure that Qt's PDF engine generates documents up to ISO-standard. Nowadays, many official institutions have the requirement to archive their data digitally and PDF is a first class […]

Qt 5.9 has just been released! This release marks two important milestones for the Qt Project. The first is that now the Qt 5 series has had more releases than any other Qt version ever (the last release of the Qt 4 series was Qt 4.8). The second milestone is that Qt 5.9 will be […]

The last blog post in this series described how to use string-views. This post is about how to design one. In particular, it's about QStringView's constructors. They evolved through a rapid succession of changes. These changes either fixed ambiguities between QString and QStringView overloads, or improved performance. And they all have the same solution: std::enable_if, […]

QZXing is a very useful library: It provides an easy to use Qt integration API around the barcode scanning library ZXing (zebras crossing). Because it is so easy to setup QZXing in a Qt application, we and most of our customers end up using it when they need to scan images for barcodes. There is, […]

In a previous blog post we introduced clazy, a clang plugin which makes the compiler understand Qt semantics, allowing you to get compile-time warnings about Qt best practices ranging from unneeded memory allocations to misuse of API, including fix-its for automatic refactoring. Today we'll do a round-up and present the checks related to connect statements, […]

A small new feature that I have added to Qt 5.8 is the possibility of disabling narrowing conversions in the new-style QObject::connect statement. In this short blog post I would like to share with you why I thought this was useful and therefore implemented it. The problem Since Qt 5.0, the new-style, PMF-based (pointer to […]

All Qt developers have asked themselves at least once in their careers: "why isn't my slot invoked?" (I've asked myself that question many, many times). There are a number of reasons why a connection may fail to be properly set up, and ultimately cause our slot not to be invoked. This blog post is a […]