Android串口通信

使用Google的开源库android-serialport-api

一、搭建项目环境

1. 在Main文件夹下创建 libs 与 jniLibs 文件夹，然后将库中对应的文件拷入

2. 在 java 文件夹下创建 android_serialport_api （注意：因为用的谷歌原生so库，所以SerialPort类的包名一定要是android_serialport_api，如果想修改这个包名，就需要重新生成对应的so库）

3. 然后在 build.gradle 中添加

   sourceSets {
       main { 
           jni.srcDirs = []
       }
   }
   

二、数据通信

• 创建串口工具类：

  public class SerialPortUtil {
  
      private static volatile SerialPortUtil serialPortUtil;
  
      private SerialPortUtil() {
  
      }
  
      public static SerialPortUtil getInstance() {
          if (serialPortUtil == null) {
              synchronized (SerialPortUtil.class) {
                  if (serialPortUtil == null) {
                      serialPortUtil = new SerialPortUtil();
                  }
              }
          }
          return serialPortUtil;
      }
  
      private SerialPort serialPort;
      private OutputStream outputStream;
      private InputStream inputStream;
  
      /**
       * 打开串口
       */
      public void openSerialPort() {
          try {
              /*设置打开的串口*/
              final String portPath = "/dev/ttyS0";
              /*设置波特率*/
              final int baudRate = 115200;
              serialPort = new SerialPort(new File(portPath), baudRate, 0);
              outputStream = serialPort.getOutputStream();
              inputStream = serialPort.getInputStream();
              /*开启线程读取数据*/
              new ReadThread().start();
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  
      /**
       * 读取数据的线程
       */
      private class ReadThread extends Thread {
          @Override
          public void run() {
              super.run();
              while (!isInterrupted()) {
                  int size;
                  try {
                      byte[] buffer = new byte[64];
                      if (inputStream == null)
                          return;
                      size = inputStream.read(buffer);
                      if (size > 0) {
                          if (dataReceiveListener != null) {
                              dataReceiveListener.receiveData(buffer, size);
                          }
                      }
                  } catch (IOException e) {
                      e.printStackTrace();
                      return;
                  }
              }
          }
      }
  
      /**
       * 关闭串口
       */
      public void closeSerialPort() {
          try {
              inputStream.close();
              outputStream.close();
              serialPort.close();
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  
      /**
       * 发送数据到串口
       *
       * @param data 需要发送的数据
       */
      public void sendDataToSerialPort(byte[] data) {
          try {
              int dataLength = data.length;
              if (dataLength > 0) {
                  outputStream.write(data);
                  outputStream.write('\n');
                  outputStream.flush();
              }
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  
      public interface DataReceiveListener {
          void receiveData(byte[] data, int size);
      }
  
      private DataReceiveListener dataReceiveListener;
  
      public void setOnDataReceiveListener(DataReceiveListener dataReceiveListener) {
          this.dataReceiveListener = dataReceiveListener;
      }
  }
  
  

• 创建串口信息获取类：

  public class SerialPortFinder {
  
      public class Driver {
          public Driver(String name, String root) {
              mDriverName = name;
              mDeviceRoot = root;
          }
          private String mDriverName;
          private String mDeviceRoot;
          Vector<File> mDevices = null;
          public Vector<File> getDevices() {
              if (mDevices == null) {
                  mDevices = new Vector<File>();
                  File dev = new File("/dev");
                  File[] files = dev.listFiles();
                  int i;
                  for (i=0; i<files.length; i++) {
                      if (files[i].getAbsolutePath().startsWith(mDeviceRoot)) {
                          Log.d(TAG, "Found new device: " + files[i]);
                          mDevices.add(files[i]);
                      }
                  }
              }
              return mDevices;
          }
          public String getName() {
              return mDriverName;
          }
      }
  
      private static final String TAG = "SerialPort";
  
      private Vector<Driver> mDrivers = null;
  
      Vector<Driver> getDrivers() throws IOException {
          if (mDrivers == null) {
              mDrivers = new Vector<Driver>();
              LineNumberReader r = new LineNumberReader(new FileReader("/proc/tty/drivers"));
              String l;
              while((l = r.readLine()) != null) {
                  // Issue 3:
                  // Since driver name may contain spaces, we do not extract driver name with split()
                  String drivername = l.substring(0, 0x15).trim();
                  String[] w = l.split(" +");
                  if ((w.length >= 5) && (w[w.length-1].equals("serial"))) {
                      Log.d(TAG, "Found new driver " + drivername + " on " + w[w.length-4]);
                      mDrivers.add(new Driver(drivername, w[w.length-4]));
                  }
              }
              r.close();
          }
          return mDrivers;
      }
  
      public String[] getAllDevices() {
          Vector<String> devices = new Vector<String>();
          // Parse each driver
          Iterator<Driver> itdriv;
          try {
              itdriv = getDrivers().iterator();
              while(itdriv.hasNext()) {
                  Driver driver = itdriv.next();
                  Iterator<File> itdev = driver.getDevices().iterator();
                  while(itdev.hasNext()) {
                      String device = itdev.next().getName();
                      String value = String.format("%s (%s)", device, driver.getName());
                      devices.add(value);
                  }
              }
          } catch (IOException e) {
              e.printStackTrace();
          }
          return devices.toArray(new String[devices.size()]);
      }
  
      public String[] getAllDevicesPath() {
          Vector<String> devices = new Vector<String>();
          // Parse each driver
          Iterator<Driver> itdriv;
          try {
              itdriv = getDrivers().iterator();
              while(itdriv.hasNext()) {
                  Driver driver = itdriv.next();
                  Iterator<File> itdev = driver.getDevices().iterator();
                  while(itdev.hasNext()) {
                      String device = itdev.next().getAbsolutePath();
                      devices.add(device);
                  }
              }
          } catch (IOException e) {
              e.printStackTrace();
          }
          return devices.toArray(new String[devices.size()]);
      }
  }
  
  

• 使用方法

  SerialPortUtil.getInstance().openSerialPort();
      SerialPortFinder finder = new SerialPortFinder();
      String[] allDevices = finder.getAllDevices();
      Log.e("LHG", Arrays.toString(allDevices));
      SerialPortUtil.getInstance().setOnDataReceiveListener(new SerialPortUtil.DataReceiveListener() {
          @Override
          public void receiveData(byte[] data, int size) {
              
          }
      });