接下来我们看看如何使用
1、新建一个测试工程，并勾选include C++ support
2、把openssl-1.1.1b/include下的openssl目录，整个复制到项目src下的cpp子目录
3、把lib下的libcryto.a和libssl.a复制到src/cpp/libs子目录
4、修改CMakeList.txt文件，在cmake_minimum_required(VERSION 3.4.1)后面添加：
#表示把src/main/cpp加入到include目录，这样在代码中使用：#include <...>就能访问到头文件
include_directories(src/main/cpp)
#添加两个预编译库
add_library(# Sets the name of the library.
openssl-crypto
# Sets the library as a static library.
STATIC
IMPORTED)
set_target_properties(
# Specifies the target library.
openssl-crypto
# Specifies the parameter you want to define.
PROPERTIES IMPORTED_LOCATION
# Provides the path to the library you want to import.
${CMAKE_SOURCE_DIR}/src/main/cpp/libs/${ANDROID_ABI}/libcrypto.a)
add_library(# Sets the name of the library.
openssl-ssl
# Sets the library as a static library.
STATIC
IMPORTED)
set_target_properties(
# Specifies the target library.
openssl-ssl
# Specifies the parameter you want to define.
PROPERTIES IMPORTED_LOCATION
# Provides the path to the library you want to import.
${CMAKE_SOURCE_DIR}/src/main/cpp/libs/${ANDROID_ABI}/libssl.a)
5、修改CMakeList.txt文件最后的target_link_libraries如下：
target_link_libraries( # Specifies the target library.
native-lib
# Links the target library to the log library
# included in the NDK.
${log-lib} openssl-ssl openssl-crypto)
6、修改native-lib.cpp返回openssl版本信息
7、启动app可以看到如下显示结果：