一：aar文件如何引用

系统Settings中引用bidehelper-1.1.12.aar 文件为例
源码地址：packages/apps/Settings/Android.mk

LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)LOCAL_SRC_FILES := \$(call all-logtags-files-under, src)LOCAL_MODULE := settings-logtagsinclude $(BUILD_STATIC_JAVA_LIBRARY)# Build the Settings APK
include $(CLEAR_VARS)LOCAL_PACKAGE_NAME := Settings
LOCAL_CERTIFICATE := platform
LOCAL_PRIVILEGED_MODULE := true
LOCAL_MODULE_TAGS := optional
LOCAL_USE_AAPT2 := trueLOCAL_SRC_FILES := $(call all-java-files-under, src)LOCAL_STATIC_ANDROID_LIBRARIES := \android-support-v4 \android-support-v13 \android-support-v7-appcompat \android-support-v7-cardview \android-support-v7-preference \android-support-v7-recyclerview \android-support-v14-preferenceLOCAL_JAVA_LIBRARIES := \bouncycastle \core-oj \telephony-common \ims-common \telephony-extLOCAL_STATIC_JAVA_LIBRARIES := \jsr305 \settings-logtags+   LOCAL_STATIC_JAVA_AAR_LIBRARIES ：= bide_helper+   LOCAL_AAPT_FLAGS := \
+      --auto-add-overlay \
+      --extra-packages com.blackberry.bidehelperLOCAL_PROGUARD_FLAG_FILES := proguard.flagsifneq ($(INCREMENTAL_BUILDS),)LOCAL_PROGUARD_ENABLED := disabledLOCAL_JACK_ENABLED := incrementalLOCAL_JACK_FLAGS := --multi-dex native
endifinclude frameworks/opt/setupwizard/library/common-gingerbread.mk
include frameworks/base/packages/SettingsLib/common.mkinclude $(BUILD_PACKAGE)+   include $(CLEAR_VARS)+   LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := \
+          bide_helper:libs/bidehelper-1.1.12.aar+   include $(BUILD_MULTI_PREBUILT)# Use the following include to make our test apk.
ifeq (,$(ONE_SHOT_MAKEFILE))
include $(call all-makefiles-under,$(LOCAL_PATH))
endif

主要代码如下：

#名称可以随便写
LOCAL_STATIC_JAVA_AAR_LIBRARIES ：= bide_helper#写入aar文件中的包名
LOCAL_AAPT_FLAGS := \--auto-add-overlay \--extra-packages com.blackberry.bidehelper

aar文件中的包名可以用压缩工具直接打开，查看AndroidManifest.xml文件

  <?xml version="1.0" encoding="utf-8" ?>
- <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.blackberry.bidehelper" android:versionCode="1" android:versionName="1.0.0.219"><uses-sdk android:minSdkVersion="21" android:targetSdkVersion="26" /> <application android:allowBackup="false" android:label="@string/app_name" android:supportsRtl="true" /> </manifest>

include $(CLEAR_VARS)#构建静态java库
LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := \bide_helper:libs/bidehelper-1.1.12.aarinclude $(BUILD_MULTI_PREBUILT)

编译后文件生成路径：out\target\product\msm8909\obj\JAVA_LIBRARIES

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