Android 设备 连接打印机

android 设备是可以连接打印机的.

而且系统版本越高,API越是完善.

我的设备是4.x的平板设备.

发现打印设备的代码:

//重要的是获取到UsbManager 这个是发现打印设备的方法
UsbDevice  usbDevice = null;
UsbManager usbManager = (UsbManager) Application.getInstance().getSystemService(Service.USB_SERVICE);
HashMap<String, UsbDevice> deviceMap = usbManager.getDeviceList();
if (deviceMap.isEmpty()) {
    if (BuildConfig.DEBUG) return;
    return;
}
Iterator<String> deviceIterator = deviceMap.keySet().iterator();
while (deviceIterator.hasNext()) {
   /**
    *device.getInterface(0).getInterfaceClass() == 7是打印机
    */
    UsbDevice device = deviceMap.get(deviceIterator.next());
    if (device.getDeviceClass() == 0 && device.getInterface(0).getInterfaceClass() == 7) {
       //这里拿到自己的打印设备 拿到设备之后可以获取到这个设备的重要信息 vid和pid
        usbDevice = device;

       //每个usb设备都有唯一的 Vid 和 Pid  就是厂商id 和 产品id
       //当知道了设备的vid,pid之后就可以很简单的做一个安卓设备连接多个打印机了
         if (1155 == device.getVendorId() && 208 == getProductId()) { //这个是已知的设备vid,pid
           //可以在这里根据需要赋值给usbDevice 
         } else if (2655 == device.getVendorId() && 1122 == getProductId()) {//这是另一个打印机的vid,pid
           //可以在这里根据需要赋值给usbDevice
           //设备可以同时连接一台,根据需要切换 相当于多台. 我项目里需要一个打印快递单,一个打印小票,就需要切换打印机
           //解决方案是写了两个打印类,分别对应两个SP文件,可以手动保存打印机的用途到Sp文件,然后对比打印机的vid,pid是否在文件
           //列表,在进行打印,好处就是可以扩展未知打印机实现各司其职的打印
         }  
    }

//获取权限  通过全局的context获取UsbManager
UsbManager usbManager = (UsbManager) Application.getInstance().getSystemService(Service.USB_SERVICE);
if (usbManager.hasPermission(usbDevice)) {
//尝试连接打印设备
    openDevice();
} else {
    PendingIntent pendingIntent = PendingIntent.getBroadcast(Application.getInstance(), 0, new Intent(
            "项目的包名.USB"), 0);
    Application.getInstance().registerReceiver(permissionReceiver,
            new IntentFilter("项目包名.USB"));
    usbManager.requestPermission(usbDevice, pendingIntent);
}
}

//尝试连接打印设备的方法
public void openDevice() {
    UsbManager usbManager = (UsbManager) Application.getInstance().getSystemService(Service.USB_SERVICE);

    usbDeviceConnection = usbManager.openDevice(usbDevice);
    if (usbDeviceConnection == null) {
        ToastUtil.showShort("连接打印机失败");
        return;
    }

    if (usbDeviceConnection.claimInterface(usbDevice.getInterface(0), true)) {
        ToastUtil.showShort("连接打印机成功");
    } else {
        ToastUtil.showShort("连接打印机失败");
        usbDeviceConnection.close();
        usbDeviceConnection = null;
    }
}

//调用UsbDeviceConnection的bulkTransfer方法进行打印

usbDeviceConnection.bulkTransfer();


//释放资源
public void onDestroy() {
    if (usbDeviceConnection != null) {
        usbDeviceConnection.close();
        usbDeviceConnection = null;
    }
    if (usbDevice != null) {
        usbDevice = null;
    }
    if (usbEndOut != null) {
        usbEndOut = null;
    }
}

 

package android.hardware.usb;

public class UsbDeviceConnection {
.........
/**
 * Performs a bulk transaction on the given endpoint.
 * The direction of the transfer is determined by the direction of the endpoint.
 * <p>
 * This method transfers data starting from index 0 in the buffer.
 * To specify a different offset, use
 * {@link #bulkTransfer(UsbEndpoint, byte[], int, int, int)}.
 * </p>
 *
 * @param endpoint the endpoint for this transaction
 * @param buffer buffer for data to send or receive
 * @param length the length of the data to send or receive
 * @param timeout in milliseconds
 * @return length of data transferred (or zero) for success,
 * or negative value for failure
 */
public int bulkTransfer(UsbEndpoint endpoint,
        byte[] buffer, int length, int timeout) {
    return bulkTransfer(endpoint, buffer, 0, length, timeout);
}

..........

}

///////////////////一个可用的Print类///////////////////////////

 

public class Print {

    private UsbDevice usbDevice;
    private UsbDeviceConnection usbDeviceConnection;
    private UsbEndpoint usbEndOut;
    private UsbEndpoint usbEndIn;

    private Print() {
    }

    static class ArgoxPrintHolder {
        static Print INSTANCE = new Print();
    }

    public static Print getInstance() {
        return ArgoxPrintHolder.INSTANCE;
    }

    public void onStart(boolean b) {

        UsbManager usbManager = (UsbManager) Application.getInstance().getSystemService(Service.USB_SERVICE);
        HashMap<String, UsbDevice> deviceMap = usbManager.getDeviceList();
        if (deviceMap.isEmpty()) {
            return;
        }
        Iterator<String> deviceIterator = deviceMap.keySet().iterator();
        while (deviceIterator.hasNext()) {
            UsbDevice device = deviceMap.get(deviceIterator.next());
            /**
             *device.getInterface(0).getInterfaceClass() == 7是打印机
             */
            if (device.getDeviceClass() == 0 && device.getInterface(0) != null && device.getInterface(0).getInterfaceClass() == 7) {
              
                if (b)
                    usbDevice = device;
                else
                    usbDevice = null;
            }
        }


        if (usbDevice == null) {
            return;
        }
        UsbInterface usbInterface = usbDevice.getInterface(0);
        for (int i = 0; i < usbInterface.getEndpointCount(); i++) {
            UsbEndpoint ep = usbInterface.getEndpoint(i);
            switch (ep.getType()) {
                case UsbConstants.USB_ENDPOINT_XFER_BULK://块
                    if (UsbConstants.USB_DIR_OUT == ep.getDirection()) {//输出
                        usbEndOut = ep;
                    } else {
                        usbEndIn = ep;
                    }
                    break;
                case UsbConstants.USB_ENDPOINT_XFER_CONTROL://控制
                    break;
                case UsbConstants.USB_ENDPOINT_XFER_INT://中断
                    break;
                default:
                    break;
            }
        }

        checkPermission();
    }

    public void checkPermission() {
        UsbManager usbManager = (UsbManager) YiApplication.getInstance().getSystemService(Service.USB_SERVICE);
        if (usbManager.hasPermission(usbDevice)) {
            openDevice();
        } else {
            PendingIntent pendingIntent = PendingIntent.getBroadcast(YiApplication.getInstance(), 0, new Intent(
                    "包名.USB"), 0);
            Application.getInstance().registerReceiver(permissionReceiver,
                    new IntentFilter("包名.USB"));
            usbManager.requestPermission(usbDevice, pendingIntent);
        }
    }

    public void openDevice() {
        UsbManager usbManager = (UsbManager) Application.getInstance().getSystemService(Service.USB_SERVICE);

        usbDeviceConnection = usbManager.openDevice(usbDevice);
        if (usbDeviceConnection == null) {
            ToastUtil.showShort("连接打印机失败");
            return;
        }

        if (usbDeviceConnection.claimInterface(usbDevice.getInterface(0), true)) {
//            ToastUtil.showShort("连接打印机成功");
        } else {
            ToastUtil.showShort("连接打印机失败");
            usbDeviceConnection.close();
            usbDeviceConnection = null;
        }
    }

    public void onDestroy() {
        if (usbDeviceConnection != null) {
            usbDeviceConnection.close();
            usbDeviceConnection = null;
        }
        if (usbDevice != null) {
            usbDevice = null;
        }
        if (usbEndOut != null) {
            usbEndOut = null;
        }
    }

    //
    @TargetApi(18)
    public boolean sendDataPrint(byte[] buffer) {
        if (buffer == null || buffer.length == 0) {
            return false;
        }
        if (usbDevice == null) {
            onStart(true);
            return false;
        }
        if (usbDeviceConnection == null) {
            checkPermission();
            return false;
        }

        boolean success = false;
        if (buffer.length > 8000) {
            int pos = 0;
            while (pos <= buffer.length) {
                if ((pos + 8000) < buffer.length) {
                    success = usbDeviceConnection.bulkTransfer(usbEndOut, buffer, pos, 8000, 500) > 0 ? true : false;
                } else {
                    success = usbDeviceConnection.bulkTransfer(usbEndOut, buffer, pos, buffer.length - pos, 500) > 0 ? true : false;
                }
                if (!success) break;
                pos = pos + 8000;
            }
        } else {
            success = usbDeviceConnection.bulkTransfer(usbEndOut, buffer, buffer.length, 500) > 0 ? true : false;
        }

        if (!success) {   //如果打印失败  直接重置打印机
            onDestroy();
            onStart(true);
        }
        return success;
    }

    private BroadcastReceiver permissionReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            if ((intent.getAction().equals("包名.USB")) &&
                    (intent.getBooleanExtra("permission", false))) {
                openDevice();
            }
        }
    };


}

 

///////使用

Print.getInstance().sendDataPrint(s.getBytes());