In this follow-up to our drag-and-drop guide, we explore how to move items between views in Qt’s model/view framework. Learn how to set up both drag and drop sides, handle MIME data, and implement key model methods. Whether you're working with model/view separation or with item widgets, this post provides practical examples to help you customize UI interactions effectively.

This blog post is the first in a series on implementing drag-and-drop in the Qt model/view framework. It covers how to reorder items within a single view, whether you're using QListView, QTableView, or QTreeView with a custom model, or QListWidget, QTableWidget, or QTreeWidget with items. The post includes code examples, checklists, and insights into improvements made in Qt 6.8 for smoother drag-and-drop functionality.

Early-Bird tickets are on sale for the KDAB Training Day 2025 until 2025-03-31 23:59 The KDAB Training Day 2025 will take place in Munich on May 8th, right after the Qt World Summit on May 6th-7th. Choose to buy a combo ticket here (for access to QtWS and Training Day) or here (for access to […]

In recent years, a lot has been happening to improve performance, maintainability and tooling of QML. Some of those improvements can only take full effect when your code follows modern best practices. Here are 10 things you can do in order to modernize your QML code and take full advantage of QML's capabilities. 1. Use […]

We’re pleased to announce the release of KD Reports 2.3.0, the latest version of our reporting tool for Qt applications. This marks our first major update in two years, bringing several bug fixes and new features that further improve the experience of generating reports. What is KD Reports? KD Reports is a versatile tool for […]

Recap In Part 1, we covered PCM audio and superimposing waveforms, and developed an algorithm to combine an arbitrary number of audio streams into one. Now we need to use these ideas to finish a full implementation using Qt Multimedia. Using Qt Multimedia for Audio Device Access So what do we need? Well, we want […]

Motivation When using Qt Multimedia to play audio files, it’s common to use QMediaPlayer, as it supports a larger variety of formats than QSound and QSoundEffect. Consider a Qt application with several audio sources; for example, different notification sounds that may play simultaneously. We want to avoid cutting notification sounds off when a new one […]

In the previous posts of this series (if you've missed them: parts 1, 2, 3, and 4), we have learned about relocation and trivial relocation. We have explored what relocation means, what trivial relocation means, and how it can be used to optimize the implementation of certain data structures, such as the reallocation of a […]

It's been around 10 months since the last release, and we're pleased to introduce GammaRay 3.1. GammaRay is a powerful tool for developers using Qt, providing deep inspection capabilities to help you understand and troubleshoot your applications. With this new release, we've made several important updates and improvements to further streamline your development process. What […]

Motivation Let’s say we’re working on a QML project that involves a TextEdit. There’s some text in it: here is some text We want to select part of this text and hit ctrl+B to make it bold: here is some text In Qt Widgets, this is trivial, but not so much in QML – we […]

You've reached the third and final entry of the Instantiating arbitrary Qt Quick components with JSON series. Part 1 and Part 2 can be found at their respective links. The first part focuses on the software design pattern used to dynamically instantiate components. The second one shows how to layout these dynamic components by incorporating […]

Qt Test is a framework designed for unit testing applications and libraries built with Qt. It provides all the standard features commonly found in unit testing frameworks, making it easier to write unit tests for Qt-based projects. We're happy to introduce the QtTest Runner - a Visual Studio Code extension for running Qt Tests via […]

KDDockWidgets has launched its latest version 2.1. This release comes packed with over 500 commits, offering enhanced stability over its predecessor, version 2.0, without introducing any breaking changes. KDDockWidgets is a versatile framework for custom-tailored docking systems in Qt written by KDAB’s Sérgio Martins. For more information about its rich set of features, have a […]

In the last post of this series we learned that: erasing elements from the middle of a vector can be implemented, in general, via a series of move assignments, move constructions, swaps, destructions for types with value semantics, the exact strategy does not really matter for types with write-through reference semantics, the strategy matters, because […]

In the last post of this series we started exploring how to erase an element from the middle of a vector. We discussed that in principle there are several different possible ways to implement erase().For instance, a vector could move-assign over the elements to be erased: Alternatively, a vector could use rotations or some other […]

I was tasked to come up with a simple architecture for remote real time instantiation of arbitrary QML components. I’ve split my findings into 3 blog entries, each one covering a slightly different topic. Part 1 focuses on the software design pattern used to dynamically instantiate components. Part 2 shows how to layout these dynamic […]

In the last post of this series we discussed the usage of trivial relocation in order to optimize move construction followed by the destruction of the source. To quickly recap: objects of certain datatypes ("trivially relocatable" types) can be moved in memory by simply moving bytes; this can be used to optimize certain bulk operations […]

The container classes introduced in Qt 4 (Tulip, for the aficionados) had an interesting optimization: the ability to turn certain operations on the contained objects into byte-level manipulations. Example: vector reallocation Consider the reallocation of a QVector<T>: when the vector is full and we want to insert a new value (of type T), the vector […]

Hotspot is a standalone GUI designed to provide a user-friendly interface for analyzing performance data. It takes a perf.data file, parses and evaluates its contents, and presents the results in a visually appealing and easily understandable manner. Our goal with Hotspot is to offer a modern alternative to perf report, making performance analysis on Linux […]

In the two previous posts (Part 1 and Part 2), we looked at how to build bindings between C++ and Rust from scratch. However, while building a binding generator from scratch is fun, it's not necessarily an efficient way to integrate Rust into your C++ project. Let's look at some existing technologies for mixing C++ […]