One of the most difficult choices to make when starting any new software project is that of the programming language and framework your team will use to create it. Should you stick with Qt because it’s the best tool for the job? Should you switch to something that uses web-based technology or is designed explicitly […]

In this article, I'd like to talk about Android storage. In recent Android versions, Google decided, for a good reason, to restrict the access to the SD card. This means, even if your application will have the old READ/WRITE_EXTERNAL_STORAGE permissions declared and granted, you won't be able to freely access the SD Card contents like […]

Porting legacy code from Motif, MFC, Photon, or a previous Qt version to a more recent Qt version can be a big challenge. There are a number of pitfalls in a large porting effort that can significantly increase time, cost, and complexity, leading to risk of project derailment. You may have languages, frameworks, and windowing […]

There are a few small, and sometimes already quite old, features in Qt that, when combined, can be a very nice way to deal with assets in your QML application -- especially if some of them live on the file system, some in a resource, and some may need localization or translation. Let's dive in! […]

With Apple moving to Apple Silicon for all of their new products, software developers are having to figure out how to support both Intel and Apple Silicon devices. Like some of our customers, you may not be ready to move to Apple Silicon. Unfortunately, that doesn't necessarily exempt you from dealing with universal binaries, especially […]

Every sizable project has a 'utils' file or folder that contains functionality that is needed more than once but too small to be a library. KDE is no different, except we want to share our 'utils' folder across hundreds of projects. This is where the KCoreAddons framework comes into play. The name comes from the […]

Some time ago, I wrote a post about integrating Qt's associative containers with the fancy new C++ features, range-based for loops with structured bindings. That post inspired KDAB's own Giuseppe D'Angelo to add the asKeyValueRange member function to both QHash and QMap. Now it's possible to iterate over them with a simple range-based for loop, […]

You have two choices when it comes to giving a custom style to your Qt widgets. Qt Style Sheets are very convenient for getting started -- just a few CSS-like rules, and they work. It is our experience, however, that Qt Style Sheets create too much trouble and a QStyle subclass (*) gives a better […]

The nlohmann/json library is everything a developer can expect from a modern library -- easy to integrate and JSON objects are treated as first class citizens with a very intuitive API. However, it has one problem that is widely mentioned across the internet, which I'll tell you about below. Various solutions to the problem have […]

C++23 is feature complete and on track to be released next year. While many people are complaining that it's, after all, a "minor" release (as the pandemic made the Committee work very difficult), C++23 still has a few very significant changes. In this blog post, I want to talk about what I think is my […]

Qt is a high quality library, but it is also massive in number of features. This massive number results in a higher likelihood that there are bugs that go unnoticed lying around in its less frequently used features or combination of features. Our friends at qgis.org hired us to solve some of those issues that […]

At KDAB, we have been investigating how to integrate Rust with Qt in a safe and idiomatic way. The solution we are currently working on is called CXX-Qt. It's available in the GitHub and on crates.io. This blog post discusses the journey of CXX-Qt -- where it started, where it can be used right now, […]

A couple of weeks ago, we guided you through setting up a chat application and server in our first blog of this series. This is the second and final blog of this Qt Allstack series. Firebase Messaging Now that we have a functional chat application, it’s time to add real world features, like push notifications. […]

Writing mobile apps can be a lot of fun, especially with Qt and QML. But if your background is all about C++ and Qt, writing the entire required stack for a mobile app can be challenging. Adding push notifications, storing information, and having to write that with another language and framework might make you give […]

Here at KDAB, we recently published a library called KDBindings, which aims to reimplement both Qt signals and slots and data binding in pure C++17. To get an introduction to the KDBindings implementation of signals and slots, I recommend that you take a look at the KDBindings Getting Started Guide. It will give you an […]

We have just released version 2.1.0 of our KDReports developer tool product. KDReports generates printable and exportable reports from code and from XML descriptions. Developers write the code that integrates KDReports with the rest of the application. External designers or marketing and sales staff can be tasked with creating the report structure, or its appearance. […]

All Qt developers should know about signals, slots, and properties. Those of you who have used QML will know that property bindings are super useful and cool. Bindings allow us to write more reactive and declarative style code. However, they are only available within QML, which means there are no compile time errors when you […]

In a well-designed QML application, the UI is built using re-usable components, while the data and logic live in C++ based components we call controllers here. The QML part of the application uses these components (that themselves may be written in QML or C++) to build up the user interface and connect these components with […]

Version 1.3.0 of the KDE Heaptrack project was just released by KDAB's Milian Wolff. Heaptrack is a heap memory profiler on Linux-based operating systems. It can help you find hotspots that need to be optimized for reducing memory usage, memory leaks, allocation hotspots, and temporary allocations. Included in this release is a special new feature […]

Another day, another small addition to KDToolBox, KDAB's collection of miscellaneous useful C++ classes and stuff. In this post, we're going to talk about KDFunctionalSortFilterProxyModel, which is a convenience subclass of QSortFilterProxyModel. What's a proxy model to begin with, and what's QSortFilterProxyModel? Well, that explanation requires a bigger space than what I have in this […]