PDA

View Full Version : Qt Quick, LGPL Dependencies, Lighthouse and a future Qt on iOS



ChrisW67
5th September 2011, 00:37
I have a bit of a general rant/query.

I would love to have a Qt path to iPad because it is simply the most assumed next step for my product (I say "assumed" because I am no longer fielding "Are you going to do an iPad version?" questions, rather "When is your iPad version available?"). I've been watching the use of the Lighthouse as a means of easing the porting Qt GUI to new platforms. I've seen proof-of-concept demos of Qt on iOS devices and things look at least possible.

However, I see the emphasis on QtDeclarative/QtQuick/QML as the UI tool of choice making this pathway a potential licence-compliance nightmare. Qt Quick has a dependency on QtScript/JavaScriptCore which imposes LGPL licensing even on commercial licence holders. The Apple guidelines require a single binary application: static linking is required to the LGPL libraries. The LGPL requires that the end-user be able to replace the LGPL components themselves, an act that is severely hampered by the locked-down device, and complicated by not having a dynamic linking ability (i.e. I must publish linkable object files or source).

The push toward this UI mechanism seems to be (further) eroding the value of a commercial licence and hindering access to much desired platforms.

How do other readers feel about this direction?