Android 扫码器串口通讯

最进接串口扫码器，参考 github上开源的串口通讯库https://github.com/cepr/android-serialport-api实现扫码器通讯。

1.集成

Android Studio使用 cmake编译，将SerialPort.c/SerialPort.h两个文件拷贝到 cpp 文件夹下，SerialPort.java拷贝到 android.serialport包下，记得包名要和SerialPort.h中的方法名中的包名一直。了解NDK开发的你懂得。
Android 扫码器串口通讯_第1张图片

CMakeLists.txt

# Sets the minimum version of CMake required to build your native library.# This ensures that a certain set of CMake features is available to# your build.cmake_minimum_required(VERSION 3.4.1)# Specifies a library name, specifies whether the library is STATIC or# SHARED, and provides relative paths to the source code. You can# define multiple libraries by adding multiple add.library() commands,# and CMake builds them for you. When you build your app, Gradle# automatically packages shared libraries with your APK.add_library( # Specifies the name of the library.        serial_port        # Sets the library as a shared library.        SHARED        # Provides a relative path to your source file(s).        src/main/cpp/SerialPort.c)find_library( # Sets the name of the path variable.        log-lib        # Specifies the name of the NDK library that        # you want CMake to locate.        log)# Specifies libraries CMake should link to your target library. You# can link multiple libraries, such as libraries you define in this# build script, prebuilt third-party libraries, or system libraries.target_link_libraries( # Specifies the target library.        serial_port        # Links the target library to the log library        # included in the NDK.        ${log-lib})

public class SerialPort {    private static final String TAG = "SerialPort";    private static final String DEFAULT_SU_PATH = "/system/bin/su";    private static String sSuPath = DEFAULT_SU_PATH;    static {        System.loadLibrary("serial_port");    }    /*     * Do not remove or rename the field mFd: it is used by native method close();     */    private FileDescriptor mFd;    private FileInputStream mFileInputStream;    private FileOutputStream mFileOutputStream;    public SerialPort(File device, int baudrate, int flags) throws SecurityException, IOException {        /* Check access permission */        if (!device.canRead() || !device.canWrite()) {            try {                /* Missing read/write permission, trying to chmod the file */                Process su;                su = Runtime.getRuntime().exec(sSuPath);                String cmd = "chmod 666 " + device.getAbsolutePath() + "\n" + "exit\n";                su.getOutputStream().write(cmd.getBytes());                if ((su.waitFor() != 0) || !device.canRead() || !device.canWrite()) {                    throw new SecurityException();                }            } catch (Exception e) {                e.printStackTrace();                throw new SecurityException();            }        }        mFd = open(device.getAbsolutePath(), baudrate, flags);        if (mFd == null) {            Log.e(TAG, "native open returns null");            throw new IOException();        }        mFileInputStream = new FileInputStream(mFd);        mFileOutputStream = new FileOutputStream(mFd);    }    public SerialPort(String devicePath, int baudrate, int flags)            throws SecurityException, IOException {        this(new File(devicePath), baudrate, flags);    }    public SerialPort(File device, int baudrate) throws SecurityException, IOException {        this(device, baudrate, 0);    }    public SerialPort(String devicePath, int baudrate) throws SecurityException, IOException {        this(new File(devicePath), baudrate, 0);    }    /**     * Set the su binary path, the default su binary path is {@link #DEFAULT_SU_PATH}     *     * @param suPath su binary path     */    public static void setSuPath(String suPath) {        if (suPath == null) {            return;        }        sSuPath = suPath;    }    // JNI    private native static FileDescriptor open(String path, int baudrate, int flags);    // Getters and setters    public InputStream getInputStream() {        return mFileInputStream;    }    public OutputStream getOutputStream() {        return mFileOutputStream;    }    public native void close();}

2.使用

public SerialPort getSerialPort()            throws SecurityException, IOException, InvalidParameterException {        if (mSerialPort == null) {            //串口：/dev/ttyS4，波特率：115200            mSerialPort = new SerialPort(new File("/dev/ttyS4"), 115200);        }        return mSerialPort;    }    public void closeSerialPort() {        if (mSerialPort != null) {            mSerialPort.close();            mSerialPort = null;        }    }private void openSerialPort() {        try {            mSerialPort =getSerialPort();            mInputStream = mSerialPort.getInputStream();            mReadThread = new ReadThread();            mReadThread.start();        } catch (SecurityException e) {            e.printStackTrace();            ToastCompat.makeText(this, R.string.error_security, Toast.LENGTH_SHORT).show();        } catch (IOException e) {            e.printStackTrace();            ToastCompat.makeText(this, R.string.error_unknown, Toast.LENGTH_SHORT).show();        } catch (InvalidParameterException e) {            e.printStackTrace();            ToastCompat.makeText(this, R.string.error_configuration, Toast.LENGTH_SHORT).show();        }    }private class ReadThread extends Thread {        public ReadThread() {        }        @Override        public void run() {            super.run();            while (!isInterrupted()) {                int size;                try {                    byte[] buffer = new byte[64];                    if (mInputStream == null) return;                    size = mInputStream.read(buffer);                    if (size > 0) {                        String goodsCode = new String(buffer, 0, size);                        EventBus.getDefault().post(new GoodsMsgEvent(goodsCode));                    }                } catch (IOException e) {                    e.printStackTrace();                    return;                }            }        }    }

1.集成

CMakeLists.txt

2.使用

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