So cool!
> Il giorno 12 ott 2020, alle ore 14:35, Frederik Seiffert > <[email protected]> ha scritto: > > Hi all, > > I’m happy to share that we launched our app "djay" on Android using GNUstep: > https://play.google.com/store/apps/details?id=com.algoriddim.djay_free > > It’s using the Android toolchain scripts to cross-compile GNUstep and its > dependencies for Android: > https://github.com/gnustep/tools-android > > The basic setup is Clang with libobjc2 using the 2.0 runtime, GNUstep-Base > and libdispatch. Those components allow us to compile and run essentially all > of our existing non-UI / non-platform specific code for Android without > changes, which is multiple 100k LOC using ARC, on 4 ABIs (armeabi-v7a, > arm64-v8a, x86, x86_64). I’m still amazed how well it all works. > > For the UI we went with Qt/QML, which turned out to be a great fit. Like > ObjC, Qt/QML is very dynamic at runtime, which enabled us to write some glue > code that lets us do two-way bindings between QML UI components and our ObjC > model using KVO/KVC. As the app is driven by Qt’s run loop, we’re driving > NSRunLoop and libdispatch from Qt, which is currently done by swizzling > NSRunLoop on launch. > > We also wrote a Java-ObjC bridge that allows us to register ObjC blocks as > native callbacks from Java (using libffi via Mike Ash’s MABlockClosure). It > e.g. allows us to hook into the Android notification system and call ObjC > methods when the user triggers playback controls on the home screen. > > It’s been a challenging but very rewarding project, and it’s also been great > to see how it improved our shared code base by forcing us to more strictly > separate platform-specific code. I’m also happy that we could make some > contributions to the GNUstep code base ourselves (67 PRs and counting ;)). > > But most importantly we really could not have done it without the incredible > work and support from the GNUstep community, including Greg, David, Fred, > Richard, Niels, Ivan, and others. Thank you all for your help! > > Frederik > >
