Support to build static Java library with Android resource
Bug: 5714516
The rationale behind this change:
- the library is compiled into a jar file, but its R class is generated
making the constant not constant (static, not final static) (aapt
option --non-constant-id). Also the jar file does not contain the R
class.
- this allows the integer value to not be inlined in the compiled
class files. Note that this prevents using switch statements.
- the main project use this jar file as a normal static library: it will
add all the class files except the R.class.
- the main project uses the library res folder as a resource
folder with lower priority than the main project (basically the
main project is an overlay. This is accomplished using aapt's
--auto-add-overlay to handle resources only in the main project
(which the normal overlay mechanism doesn't allow).
- the main project creates R classes in the main project's
package but also in the library's package. This is done with
aapt's --extra-packages which accept as many packages as
needed, separated by a :.
- manifest merging is not done yet, so
activities/services/permissions/etc... have to be manually declared in
the main app.
To use a static library with Android resource in your app,
1. Add the library's resource dir to your app as an overlay:
LOCAL_RESOURCE_DIR := <app_resource_dir> <static_library_resource_dirs>
2. Set the proper aapt flags:
LOCAL_AAPT_FLAGS := <apps_own_flags> --auto-add-overlay \
--extra-packages <lib1_package_name>:<lib2_package_name>:...
Change-Id: Ifb4d2300b952ea4aaee74da1bb0c6c72ea0698a3
diff --git a/core/definitions.mk b/core/definitions.mk
index e950d38..f16b4c9 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1408,6 +1408,9 @@
# For a list of jar files, unzip them to a specified directory,
# but make sure that no META-INF files come along for the ride.
+# We also remove any R.class/Manifest.class from the jar files;
+# R/Manifest class for the static Java libraries should be
+# re-generate in the app module instead.
#
# $(1): files to unzip
# $(2): destination directory
@@ -1421,6 +1424,7 @@
unzip -qo $$f -d $(2); \
(cd $(2) && rm -rf META-INF); \
done
+ $(hide) find $(2) -name 'R.class' -o -name 'R$$*.class' -o -name 'Manifest.class' -o -name 'Manifest$$*.class' | xargs rm -rf
endef
# Common definition to invoke javac on the host and target.