Whenever I see something like this, my first question is, wow what a beautiful cross-platform UI -- I wonder what they are using?
It's amazing how challenging it is in 2020 to have a simple path for creating a cross-platform UI that actually looks good and is not aimed at developers as users, but rather competes with the polish of established applications. Unless you go with Electron or pay thousands per year for a Qt license, options are quite limited.
Why does everyone keep repeating the "pay for a Qt license" meme every time that someone presents a Qt software? You do not need to pay for a Qt license, it is under lgpl, just like a lot of other libraries that you can use in both foss and non-foss applications. Even GTK which some replies suggested uses the LGPL! Same goes for glibc which you link all of your programs to.
IBM / Redhat reputation managers want you on systemd + gnome + wayland. Their natterings reach all corners of the Internet. It's concerted, shameless, and it's really starting to get irritating.
The sheer pervasiveness across all platforms with unified messaging indicates faux grassroots shillops. Super easy to spot these days. Over-shilling broke the reputation management industry.
The license for QT has been evolving quite a lot over the last year or two, which makes many developers very nervous to use it without a paid license. Have you seen what they’re doing?
The terms of their commercial license may have been evolving, but the terms of the open source has not. GPL is GPL and LGPL is LGPL. The terms of those licenses prohibit additional restrictions (notably, you are not allowed to add a noncommercial clause to the GPL/LGPL) and the Qt company cannot make their own open source license that is noncommercial otherwise they'd violate the KDE Free Qt Agreement. The most they seem to have been thinking about doing was witholding the open source releases for 12 mo. which is unfortunate, but they are required to keep an open source version around because of the KDE Free Qt Agreement[1], otherwise they are required to release the framework under the BSD license.
Autodesk Maya notably does not use a commercial Qt license, they use it under the LGPL. You can find the source code for their patches of Qt on their website. [2]
Maybe they simply see no value in keeping their modifications to qt to themselves and value in up streaming it ensuring they no longer have to maintain the code. This makes a lot of sense they are in the business of providing world class software not gui frameworks.
I am not sure if it's still this way, but I think at least some versions of the Qt Commercial License disallowed you from having user scripting in your application - or at least, exposing Qt APIs to user scripting. So no bindings like PySide or PyQt and the like could be used.
> In case The Qt Company would ever attempt to close down Open Source Qt, the foundation is entitled to publish Qt under the BSD license. This notable legal guarantee strengthens Qt. It creates trust among developers, contributors and customers.
Content production tools have fairly unique UI needs compared to the average desktop application, e.g. they often have very complex timeline controls that offer dozens if not hundreds of different interactions specific to the tool at hand. Generic UI libraries would only be a hindrance there. They almost never have enough screen space, so the widget/interaction density is far greater than what’d be ergonomic for standard apps. Since people spend considerable time learning these tools they generally have their own UI paradigms independent of the host OS, which is the opposite of what you‘d want in a crossplatform toolkit.
I have argued in the past that any app worth a damn will not use some generic off-the-shelf widget kit. This includes even apps such as Excel or Word.
The reasons for this are that GUI widget kits are generalized to the least common denominator. They are written with a specific, narrow usage in mind and will never fit your application to the degree you need. And in some cases the author of a certain widget tries to do this, and the widget succumbs to the weight of complexity required to be all things to all people. Not even GIMP uses only GTK+.
The second reason that staying in one widget kit is bad is because it's a competitive world out there. You need to differentiate. That's not easy when every app looks and feels the same because they all use the same tool kit.
In addition to all of this, different OSes have different UX. A Qt app on Mac is not going to be identical to a Qt app on Linux. Assuming the Qt app is written to the guidelines of the OS and not just doing whatever it wants. Internally, the app will do what is best (e.g. photoshop canvas), but will play nice with the external window manager, accessibility, etc.
Word/Office is such a good example because they use their own window decorations, ribbon, scroll bars etc., which no other program (even from MS) has, and no second source implementation with exactly the same features exists.
the question is not really whether they use Qt. It's how much of Qt they use. Ardour, for example, uses GTK, but hardly uses any of GTK for the majority of the GUI.
It's amazing how challenging it is in 2020 to have a simple path for creating a cross-platform UI that actually looks good and is not aimed at developers as users, but rather competes with the polish of established applications. Unless you go with Electron or pay thousands per year for a Qt license, options are quite limited.