Android Studio 3.5导入AOSP编译的class
一、适用场景
我们在写应用时可能会需要调用系统隐藏的API,这些API是我们无法直接访问的,报如下错误:
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此时,我们需要将系统AOSP的out/target/common/obj/JAVA_LIBRARIES/framework_intermediates/classes.jar导入到Android Studio中,使app能够访问这些接口。
二、实现步骤
Step1. 在app目录下建立libs文件夹,并将classes.jar包放入该路径
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Step2.在app目录上右键【Open Module Settings】,点击左侧【Dependencies】,选择app,点击【+】选择【2 Jar Dependency】,添加
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选择我们的libs/classes.jar,点击【OK】
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Step3.在Module的build.gradle中,dependencies自动增加依赖配置,注释掉下面一行
implementation fileTree(dir: 'libs', include: ['*.jar'])
并将implementation files('libs/classes.jar')改为
compileOnly files('libs/classes.jar')
最终如下图所示
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Step4.修改Project的build.gradle,在allProjects中增加如下语句
gradle.projectsEvaluated {
tasks.withType(JavaCompile) {
options.compilerArgs.add('-Xbootclasspath/p:app\\libs\\classes.jar')
}
}
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Step5.修改jar包优先级,在Moduels的app.iml文件中找到我们的classes.jar包所在行,
<orderEntry type="library" name="Gradle: __local_aars__:/Users/mrwong/AndroidStudioProjects/uart_daemon/app/libs/classes.jar:unspecified@jar" level="project" />
将其移动到
<orderEntry type="jdk" jdkName="Android API 29 Platform" jdkType="Android SDK" />
这一行之上,最终如下图所示:
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至此,app可以优先访问我们自己的jar包 。