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by dx87 2395 days ago
> I always wonder why Qt5+/Qml/QtQuick have not taken the XP desktop development by storm.

If I had to guess, it's because people are misinformed about the pricing and features. I regularly see people who assume that you either have to pay a large per-developer fee, or completely open source your application, even though Qt is licensed under the LGPL, so you're fine as long as you don't statically link it or depend on secret modifications to Qt for your application. A lot of people also assume it only supports C++ and dismiss it outright.
1 comments
jacobush 2395 days ago
LGPL is problematic for App Store, since the user should be able to relink the app with a newer version [of QT] if they wanted to.
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de_watcher 2395 days ago
They can relink. The object files for relinking aren't required to go through App Store.

Static/dynamic linking isn't a problem.

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jacobush 2395 days ago
Interesting. If I install this [0] app, how can I relink it against my patched QT5?

0: https://apps.apple.com/us/app/qt-5-showcases-by-v-play-apps/...

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de_watcher 2394 days ago
Normally you ask them for the object files, but those specific guys are middleware developers so they provide QtCreator configured to build with their library (to get a different Qt version, select a different Qt Kit in QtCreator settings).

Additionally, the nature of the library is that it's probably a plugin that's loaded by a regular Qt application, as a result you've got their classes available in the QML scripts. It isn't very intrusive on the practical level.

They don't say what license they use though.

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jcelerier 2394 days ago
Felgo most certainly uses Qt through the commercial license so nothing is LGPL here.
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jacobush 2394 days ago
Right. Now imagine it didn't. What then?
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jcelerier 2394 days ago
you ask them for the LGPL package, they send it to you, you compile ?

The onus is on the person making the app that links against the LGPL library to provide you with the build instruction.

At worse they would give you their main static library and Qt LGPL source code and you just have to relink them and open Xcode to upload it to your iDevice ?

Here is for instance the source code for the telegram app for iOS which is under GPL : https://github.com/TelegramMessenger/Telegram-iOS

there is no difference with... basically every other open source project ? Open the .xcodeproj, build, run.

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