Building applications for Android
Building .apk files from Qt Applications requires a cross-compiling toolchain, which is hard to setup. To simplify this, there is a ready-to-use Docker container for building KDE applications.
This documentation only applies to applications that have a Craft blueprint in the craft-blueprints-kde repository. If the application you want does not have such a blueprint yet, have a look at the documentation.
The container can be initialized with
mkdir craft-kde-android docker run -ti --rm -v $PWD/craft-kde-android:/home/user/CraftRoot kdeorg/android-qt515 bash python3 -c "$(curl https://raw.githubusercontent.com/KDE/craft/master/setup/CraftBootstrap.py)" --prefix ~/CraftRoot
NoteIf this fails with an error similar to "Permission denied", you may need to disable SELinux while using craft by running
sudo setenforce 0
Craft will prompt you for the desired target architecture (arm32, arm64, x86_32 or x86_64) and possible other prompts.
To build an application you first need to enter the container using
docker run -ti --rm -v $PWD/craft-kde-android:/home/user/CraftRoot kdeorg/android-qt515 bash
and source the Craft environment with
Now run Craft commands like
craft <appname> to build an application and
craft --package <appname> to package it as apk.
Inside the Craft environment, the blueprints can be found by running
cs craft-blueprints-kde and can be edited there to quickly test changes.
The source folder for an application or library can be found the same way by running
cs <projectname>; the build folder can be found by running
You can quickly iterate on patches for a project by editing it in the source folder, followed by calling
ninja install in the build folder and creating an apk file using
craft --package <appname>.
There are much more Craft commands, take a look at the Craft documentation to learn about them.
.apk file can be found at
/home/user/CraftRoot/tmp. This folder is also available as
craft-kde-android/tmp on the host system. Craft does not sign the apks, so you need to do that yourself before being able to install it onto a device. For signing an apk, you need to create a signing key first, which can be done using
keytool -genkey -noprompt -keystore key.keystore -keypass 123456 -dname "CN=None, OU=None, O=None, L=None, S=None, C=XY" -alias mykey -keyalg RSA -keysize 2048 -validity 10000 -storepass 123456
This key can be reused to sign all of your development apks.
Before signing the apk, it might be needed to align it. This can be done using
zipalign -p -f -v 4 <app>.apk <app>.signed.apk
You can finally sign the aligned apk with your key using
apksigner sign -verbose -ks key.keystore <app>.signed.apk
apksigner binaries can be found at
/opt/android-sdk/build-tools/<version>/ inside the Craft container environment.