Unity Adroid串口Dll not found Exception : MonoPosixHelper第二种解决办法

如题，第一种办法前文已给，但是略显麻烦，因为还要导出成Eclipse或者Android Studio，然后java 什么的 覆盖一堆 然后开其他重新编译，不是说不可以，至少浪费十几秒时间？假定你电脑都是神速，你也是神操作的话，至少10秒得要吧？好，第二种办法来了，灵感来自于libsqlite.so，既然sqlite都可以用c++的方式去直接完成调用，我们何必c++---java---unity这样中转呢？这不是浪费效率吗？所以办法如下：、1、将此文件serial.cpp，Android.mk Application.mk放入jni文件夹。（哪里的jni？请随意，你高兴在哪创建都可以）

//包含头文件#include <stdio.h>#include <stdlib.h>#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#ifndef _WIN32 #include <sys/ioctl.h>#include <unistd.h>#include <termios.h>#else#include <io.h>#pragma warning (disable:4996)#endif#include <errno.h>#include <string.h>#include <time.h>intfd_ = -1;extern "C" {int set_opt(int fd, int nSpeed, int nBits, char nEvent, int nStop, int min_btye);}long long  getMilisec(){#ifndef _WIN32 struct timeval now;gettimeofday(&now, NULL);long long  t_mili = ((long long)now.tv_sec) * 1000 + now.tv_usec / 1000;return t_mili;#elsereturn 0;#endif}//打印//#include "android/log.h"//static const char *TAG = "HelloWorldScene";//#define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO, TAG, fmt, ##args)//#define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args)//#define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args)extern "C"  {bool Serial_Open(){if (fd_ > 0)//already openreturn true;#ifndef _WIN32//char *dev[] = { "/dev/ttySAC0", "/dev/ttySAC1", "/dev/ttySAC2", "/dev/ttySAC3" };//long vdisable;fd_ = open("/dev/ttyS2", O_RDWR | O_NOCTTY | O_NDELAY);if (fd_ == -1) {return false;}//LOGE("Open Serial Port %s\n",dev[comport]);//恢复串口为阻塞状态if (fcntl(fd_, F_SETFL, 0) < 0) {return false;}/*测试是否为终端设备*/if (isatty(STDIN_FILENO) == 0) {//LOGE("standard input is not a terminal device\n");}set_opt(fd_, 115200, 8, 'N', 1, 200);#elsefd_ = open("/dev/ttyS2", O_RDWR);if (fd_ == -1) {return false;}#endifreturn fd_ > 0;}void Serial_Close(){if (fd_ > 0){close(fd_);fd_ = -1;}}int Serial_SendData(const unsigned char* data, int size){if (fd_ < 0)//not openreturn -1;int ret = write(fd_, data, size);return ret;}int Serial_RecvData(unsigned char* buff, int len){if (fd_ < 0)//not openreturn -1;memset(buff, 0, len);int readSize = read(fd_, buff, len);return readSize;}/***************************** * 功能：设置串口函数 * 入口：（fd，波特率，数据位，奇偶校验，停止位） *****************************/int set_opt(int fd, int nSpeed, int nBits, char nEvent, int nStop, int min_btye){#ifndef _WIN32struct termios newtio, oldtio;/*保存测试现有串口参数设置，在这里如果串口号出错，会有相关的出错信息*/if (tcgetattr(fd, &oldtio) != 0) {// LOGE("SetupSerial 1");return -1;}bzero(&newtio, sizeof(newtio));/*步骤一：设置字符大小*/newtio.c_cflag |= CLOCAL | CREAD;newtio.c_cflag &= ~CSIZE;/*设置停止位*/switch (nBits) {case 7: newtio.c_cflag |= CS7;break;case 8: newtio.c_cflag |= CS8;break;}/*设置奇偶校验位*/switch (nEvent) {case 'O': //奇数newtio.c_cflag |= PARENB;newtio.c_cflag |= PARODD;newtio.c_iflag |= (INPCK | ISTRIP);break;case 'E': //偶数newtio.c_iflag |= (INPCK | ISTRIP);newtio.c_cflag |= PARENB;newtio.c_cflag &= ~PARODD;break;case 'N': //无奇偶校验位newtio.c_cflag &= ~PARENB;break;}/*设置波特率*/switch (nSpeed){case 2400:cfsetispeed(&newtio, B2400);cfsetospeed(&newtio, B2400);break;case 4800:cfsetispeed(&newtio, B4800);cfsetospeed(&newtio, B4800);break;case 9600:cfsetispeed(&newtio, B9600);cfsetospeed(&newtio, B9600);break;case 19200:cfsetispeed(&newtio, B19200);cfsetospeed(&newtio, B19200);break;case 115200:cfsetispeed(&newtio, B115200);cfsetospeed(&newtio, B115200);break;case 460800:cfsetispeed(&newtio, B460800);cfsetospeed(&newtio, B460800);break;default:cfsetispeed(&newtio, B115200);cfsetospeed(&newtio, B115200);break;}/*设置停止位*/if (nStop == 1) {newtio.c_cflag &= ~CSTOPB;}else if (nStop == 2) {newtio.c_cflag |= CSTOPB;}/*设置等待时间和最小接收字符*/newtio.c_cc[VTIME] = 1;newtio.c_cc[VMIN] = min_btye;/*处理未接收字符*/tcflush(fd, TCIFLUSH);/*激活新配置*/if ((tcsetattr(fd, TCSANOW, &newtio)) != 0) {// LOGE("COM set error\n");return -1;}#endifreturn 0;}}

## Copyright 2009 Cedric Priscal# # Licensed under the Apache License, Version 2.0 (the "License");# you may not use this file except in compliance with the License.# You may obtain a copy of the License at# # http://www.apache.org/licenses/LICENSE-2.0# # Unless required by applicable law or agreed to in writing, software# distributed under the License is distributed on an "AS IS" BASIS,# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.# See the License for the specific language governing permissions and# limitations under the License. #LOCAL_PATH := $(call my-dir)include $(CLEAR_VARS)NDK_TOOLCHAIN_VERSION := 4.9LOCAL_C_INCLUDES := C:/android-ndk-r15b/sources/cxx-stl/gnu-libstdc++/4.9/includeLOCAL_C_INCLUDES +=C:\android-ndk-r15b\sources\cxx-stl\gnu-libstdc++\4.9\libs\armeabi\includeTARGET_PLATFORM := android-18LOCAL_MODULE    := serialportLOCAL_SRC_FILES := serial.cppLOCAL_LDLIBS    := -llogLOCAL_CPPFLAGS := -std=c++11 -D __cplusplus=201103LAPP_STL := gnustl_sharedAPP_CPPFLAGS := -std=c++11 -frtti -fexceptionsAPP_CPPFLAGS += -std=gun++11 -lpthreadinclude $(BUILD_SHARED_LIBRARY)

applacation.mk

APP_ABI := armeabi armeabi-v7a x86

sorry 不会用csdn的排版。好渣

2、将ndk目录设置为Path环境变量。直到ndk-build命令正常找到为止。
3、定位到jni目录，运行ndk-build.


4、运行成功，到外面的lib\armeabi下将生成的libserialport.so放入unity的Plugins/Android下。
5、打开你喜欢的脚本文件。放入如下代码


 [DllImport("serialport")]
    private static extern bool Serial_Open();


    [DllImport("serialport")]
    private static extern void Serial_Close();


    [DllImport("serialport")]
    private static extern int Serial_SendData(byte[] com_data, int size);


    [DllImport("serialport")]
    private static extern int Serial_RecvData(byte[] com_data, int size);


就可以成功在安卓下使用串口了。不必让我说如何使用了吧。就4个接口！