Android 生成so库 并调用

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第一步：创建so库

第二步：看一下Native的项目结构

自动生成引用文件build.gradle（app）

 externalNativeBuild { cmake { path file('src/main/cpp/CMakeLists.txt') version '3.22.1' } } //每个版本的开发工具不一样 我这个是自动生成的so库文件类型，尽量用新版ASK开发工具

CMakeLists.txt

# For more information about using CMake with Android Studio, read the
# documentation: https://d.android.com/studio/projects/add-native-code.html.
# For more examples on how to use CMake, see https://github.com/android/ndk-samples.

# Sets the minimum CMake version required for this project.
cmake_minimum_required(VERSION 3.22.1)

# Declares the project name. The project name can be accessed via ${ PROJECT_NAME},
# Since this is the top level CMakeLists.txt, the project name is also accessible
# with ${CMAKE_PROJECT_NAME} (both CMake variables are in-sync within the top level
# build script scope).
project("sodemo")

# Creates and names a library, sets it as either STATIC
# or SHARED, and provides the relative paths to its source code.
# You can define multiple libraries, and CMake builds them for you.
# Gradle automatically packages shared libraries with your APK.
#
# In this top level CMakeLists.txt, ${CMAKE_PROJECT_NAME} is used to define
# the target library name; in the sub-module's CMakeLists.txt, ${PROJECT_NAME}
# is preferred for the same purpose.
#
# In order to load a library into your app from Java/Kotlin, you must call
# System.loadLibrary() and pass the name of the library defined here;
# for GameActivity/NativeActivity derived applications, the same library name must be
# used in the AndroidManifest.xml file.
add_library(${CMAKE_PROJECT_NAME} SHARED
        # List C/C++ source files with relative paths to this CMakeLists.txt.
        native-lib.cpp
        src/NativeImpl.cpp)

# Specifies libraries CMake should link to your target library. You
# can link libraries from various origins, such as libraries defined in this
# build script, prebuilt third-party libraries, or Android system libraries.
target_link_libraries(${CMAKE_PROJECT_NAME}
        # List libraries link to the target library
        android
        log)

native-lib.cpp

#include <jni.h> #include <string> #include "src/NativeImpl.h" /* 获取NativeImpl */ NativeImpl nativeImpl; NativeImpl *getNativeImpl() { return &nativeImpl; } extern "C" JNIEXPORT jstring JNICALL Java_com_geek_sodemo_NativeImpl_ICC_1interface_1power(JNIEnv *env, jclass clazz) { // TODO: implement ICC_interface_power() // TODO: implement getUserName() char *c = getNativeImpl()->ICC_interface_power(); return env->NewStringUTF(c); }

第三步：直接加上so库代码优化(不废话)

把native-lib.cpp分离出来创建 .h和.cpp文件 如下代码

NativeImpl.cpp

#include "NativeImpl.h" NativeImpl::NativeImpl() { } NativeImpl::~NativeImpl() { } char *NativeImpl::ICC_interface_power() { // 这里处理代码逻辑 return "卡槽上下电控制"; }

NativeImpl.h

#ifndef MYNATIVE_CLIENTIMPL_H #define MYNATIVE_CLIENTIMPL_H #include <vector> class NativeImpl { public: NativeImpl(); virtual ~NativeImpl(); virtual char* ICC_interface_power(); }; #endif //MYNATIVE_CLIENTIMPL_H

第四步:在CMakeLists.txt文件中增加cpp引入

add_library(${CMAKE_PROJECT_NAME} SHARED # List C/C++ source files with relative paths to this CMakeLists.txt. native-lib.cpp src/NativeImpl.cpp)

native-lib.cpp增加方法

#include <jni.h> #include <string> #include "src/NativeImpl.h" /* 获取NativeImpl */ NativeImpl nativeImpl; NativeImpl *getNativeImpl() { return &nativeImpl; } extern "C" JNIEXPORT jstring JNICALL Java_com_geek_sodemo_NativeImpl_ICC_1interface_1power(JNIEnv *env, jclass clazz) { // TODO: implement ICC_interface_power() // TODO: implement getUserName() char *c = getNativeImpl()->ICC_interface_power(); return env->NewStringUTF(c); }

第五步:so库使用优化NativeImpl创建在应用的目录结构下

public class NativeImpl { // 加载so库 static { System.loadLibrary("sodemo"); } / * 添加 native 方法 */ public static native String ICC_interface_power(); } 

MainActivity.class中进行引用

public class MainActivity extends AppCompatActivity { private ActivityMainBinding binding; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); binding = ActivityMainBinding.inflate(getLayoutInflater()); setContentView(binding.getRoot()); // Example of a call to a native method TextView tv = binding.sampleText; tv.setText(NativeImpl.ICC_interface_power()); } }

最后运行看结果

上面的内容生成so库及给java代码调用就完成了

下面是怎样是这个so库给其他应用使用  如下

然后拷贝.so文件到 新创建的项目中的libs文件下 

 在build.gradle 里面android节点下增加

sourceSets { main { jniLibs.srcDirs = ['libs'] } }