Android studio编译JNI遇到的坑

1.加载build.gradle文件里面通过

externalNativeBuild {

cmake {

path file('src/main/cpp/CMakeLists.txt')

version '3.18.1'

}

}

加载CMakeList.txt文件

报错

1.加载demo项目，grader编译使用的SDK不是合适当前APP版本，需要修改成29的版本，或者本地as下载对应的31的sdk，minSDK版本最小适应26

2.移植过来的demo，JNI无法加载，显示搜不到对应的JNI方法，SDK插件版本与NDK版本不一致，导致搜索不到对应的JNI方法

3.打开Project Structure 默认是没有NDK的，手动安装NDK确保编译正常

4.报错

[CXX1405] error when building with cmake using D:\gongzuo\demo\FASTDDSServer-master\app\src\main\cpp\CMakeLists.txt: Build command failed.

Error while executing process C:\Users\user\AppData\Local\Android\Sdk\cmake\3.18.1\bin\cmake.exe with arguments {-HD:\gongzuo\demo\FASTDDSServer-master\app\src\main\cpp -DCMAKE_SYSTEM_NAME=Android -DCMAKE_EXPORT_COMPILE_COMMANDS=ON -DCMAKE_SYSTEM_VERSION=26 -DANDROID_PLATFORM=android-26 -DANDROID_ABI=arm64-v8a -DCMAKE_ANDROID_ARCH_ABI=arm64-v8a -DANDROID_NDK=C:\Users\user\AppData\Local\Android\Sdk\ndk\21.4.7075529 -DCMAKE_ANDROID_NDK=C:\Users\user\AppData\Local\Android\Sdk\ndk\21.4.7075529 -DCMAKE_TOOLCHAIN_FILE=C:\Users\user\AppData\Local\Android\Sdk\ndk\21.4.7075529\build\cmake\android.toolchain.cmake -DCMAKE_MAKE_PROGRAM=C:\Users\user\AppData\Local\Android\Sdk\cmake\3.18.1\bin\ninja.exe -DCMAKE_CXX_FLAGS=-std=c++11 -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=D:\gongzuo\demo\FASTDDSServer-master\app\build\intermediates\cxx\Debug\4t4fd482\obj\arm64-v8a -DCMAKE_RUNTIME_OUTPUT_DIRECTORY=D:\gongzuo\demo\FASTDDSServer-master\app\build\intermediates\cxx\Debug\4t4fd482\obj\arm64-v8a -DCMAKE_BUILD_TYPE=Debug -BD:\gongzuo\demo\FASTDDSServer-master\app.cxx\Debug\4t4fd482\arm64-v8a -GNinja}

存在CXX1405 这样的保存，且NDK可以使用但是无法生成os库，原因是因为DLL文件损坏导致，需要到网上去下载DLL库放置到C:\Windows\System32目录下，再执行 cmake成功

C:\Users\user\AppData\Local\Android\Sdk\cmake\3.18.1\bin>cmake.exe

Usage

cmake [options]

cmake [options]

cmake [options] -S -B

Specify a source directory to (re-)generate a build system for it in the

current working directory. Specify an existing build directory to

re-generate its build system.

Run 'cmake --help' for more information.

2.Cannot resolve corresponding JNI function Java_com_example_fastddsserver_MainActivity_ddsSayHellow. 无法解析对应的JNI函数

解决方案

1.去除勾选的Adroid NDK Support插件

2.检查NDK和SDK的版本

3.检查是否有阻止使用C++的插件

4.将Adroid NDK Support插件勾选回来，支持NDK

5.重启Android Studio