NOTE: This commit does not touch the ant build system at all,
only gradle.
There are currently 23 gradle projects which require configuration,
let alone building, in order to build F-Droid. This takes a non-trivial
amount of time/memory/cpu. Additionally, it also provides difficulties
when importing the project into Android Studio - which is the IDE that
many potential contributors will be using. Finally, I have over 100mb
of data in the extern/ folder, and the support libraries require almost
every single Android SDK to be installed, which is several GB. This is
not a friendly environment to encourage people to submit merge requests.
However, I'm very mindful of the need for an open source project such
as F-Droid to be able to be built from source. So to make sure we have
the best of both worlds, I've ensured that building all dependencies
from source is still possible.
The F-Droid/libs/README.md file explains in greater detail how to
do this (i.e. "gradle -PsourceDeps build").
As much as possible, I've tried to make the binary dependencies fetched
from jcenter. However there are still libraries which either haven't
integrated required changes for F-Droid back upstream, or don't have
mavenCentral/jcenter binaries available.
Android preference fragment has been changed to the original
upstream repository. The one we had before was because upstream
hadn't merged a MR for gradfle support yet. However, that has
now been merged. This version still doesn't exist in jcenter though.
In order for libsuperuser to build from upstream, using
`gradle -PsourceDeps`, we need to include a few gradle plugins
from jcenter which are never actually used (used by upstream to
release to jcenter).
Even though support-v4 is included through jcenter, it is kept in
the libs directory, so that ./ant-prepare.sh can use it.
Update support preference fragment to newer version. There has been
bugfixes commited, so lets include them in the version we are using.
The specific reason for this is that it provides @Null and @NotNull
annotations which should increase the safety of our code. Many of the
bugs which get filed are due to NullPointerExceptions, which could be
avoided by tooling using these annotations. The goal is to statically
catch this specific class of errors in as many situations as possible,
rather than waiting for them to occur at runtime.
Although Google is encouraging people to make old devices run apps
with the action bar (via appcompat-v7), they haven't provided a way
for people to create preference/setting screens with an action bar.
There are plenty of issues in the Android issue tracker relating
to this, but it doesn't yet seem to be on the radar of the Android
devs.
Until there is a native implementation of PreferenceFragment in
the appcompat-v7 support library, this submodule provides is a 3rd
party solution. It is actually a fork of the first repo in github,
though that was a bit of an upload and dump, without accepting MR's.
This fork includes gradle support.