package com.example.appproto1;
import android.app.Activity;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.hardware.usb.UsbDeviceConnection;
import android.hardware.usb.UsbManager;
import android.os.AsyncTask;
import android.os.Handler;
import android.os.SystemClock;
import android.util.Log;
import com.hoho.android.usbserial.driver.UsbSerialDriver;
import com.hoho.android.usbserial.driver.UsbSerialPort;
import com.hoho.android.usbserial.driver.UsbSerialProber;
import com.hoho.android.usbserial.util.SerialInputOutputManager;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class USBSerialConnector implements SerialInputOutputManager.Listener {
private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
private static final String TAG = "USBSerialConnector";
private static boolean hasPermission = false;
private SerialInputOutputManager serialIOManager;
private final ExecutorService executor = Executors.newSingleThreadExecutor();
private UsbManager usbManager;
private UsbSerialPort serialPort;
private USBSerialListener usbSerialListener;
private Handler handlerTimeOut;
private Context mContext;
private static USBSerialConnector instance = null;
private Runnable timeOutRunnable = new Runnable() {
@Override
public void run() {
usbSerialListener.onDataReceived(null);
}
};
public static USBSerialConnector getInstance() {
if (instance == null) {
instance = new USBSerialConnector();
}
return instance;
}
public void init(Context context, final int baudRate) {
mContext = context;
usbManager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
/**
* Receiver to USB Permission
*/
BroadcastReceiver usbReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
SystemClock.sleep(1000);
List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(usbManager);
if (availableDrivers != null && !availableDrivers.isEmpty()) {
UsbSerialDriver driver = availableDrivers.get(0);
List<UsbSerialPort> ports = driver.getPorts();
if (!ports.isEmpty()) {
serialPort = ports.get(0);
context.unregisterReceiver(this);
hasPermission = true;
new SetUsbSerialDriver().execute(baudRate);
}
}
}
}
}
};
PendingIntent mPermissionIntent = PendingIntent.getBroadcast(context, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
context.registerReceiver(usbReceiver, filter);
SystemClock.sleep(1000);
List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(usbManager);
if (availableDrivers != null && !availableDrivers.isEmpty()) {
// Open a connection to the first available driver.
UsbSerialDriver driver = availableDrivers.get(0);
List<UsbSerialPort> ports = driver.getPorts();
// Read some data! Most have just one port (port 0).
if (!ports.isEmpty()) {
serialPort = ports.get(0);
Log.d(TAG, "Port: " + serialPort);
if (!hasPermission) {
usbManager.requestPermission(serialPort.getDriver().getDevice(), mPermissionIntent);
} else {
new SetUsbSerialDriver().execute(baudRate);
}
} else {
Log.d(TAG, "USB Serial device not found");
usbSerialListener.onDeviceReady(ResponseStatus.ERROR);
}
} else {
onDeviceStateChange(ResponseStatus.ERROR);
}
registerOnDeviceDisconnected(context);
}
public void pausedActivity() {
stopIOManager();
if (serialPort != null) {
try {
serialPort.close();
} catch (IOException e) {
usbSerialListener.onErrorReceived(Utilities.getStackTrace(e));
}
serialPort = null;
}
}
private void stopIOManager() {
if (serialIOManager != null) {
serialIOManager.stop();
serialIOManager = null;
}
}
private void startIOManager() {
if (serialPort != null) {
serialIOManager = new SerialInputOutputManager(serialPort, this);
executor.submit(serialIOManager);
}
}
private void onDeviceStateChange(ResponseStatus responseStatus) {
stopIOManager();
startIOManager();
usbSerialListener.onDeviceReady(responseStatus);
}
private void registerOnDeviceDisconnected(Context context) {
BroadcastReceiver receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
if (intent.getAction().equals(UsbManager.ACTION_USB_DEVICE_DETACHED)) {
usbSerialListener.onDeviceDisconnected();
}
}
};
IntentFilter filter = new IntentFilter();
filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
context.registerReceiver(receiver, filter);
}
public void setUsbSerialListener(USBSerialListener usbSerialListener) {
this.usbSerialListener = usbSerialListener;
}
private void removeTimeOutCallbacks() {
if (handlerTimeOut != null) {
handlerTimeOut.removeCallbacks(timeOutRunnable);
}
}
public void write(byte[] data, int timeoutMillis) {
handlerTimeOut = new Handler();
if (serialIOManager != null) {
serialIOManager.writeAsync(data);
handlerTimeOut.postDelayed(timeOutRunnable, timeoutMillis);
} else {
usbSerialListener.onErrorReceived("Null SerialIOManager");
}
}
public void writeAsync(byte[] data){
if (serialIOManager != null) {
serialIOManager.writeAsync(data);
} else {
usbSerialListener.onErrorReceived("Null SerialIOManager");
}
}
@Override
public void onNewData(final byte[] data) {
//removeTimeOutCallbacks();
Log.d(TAG, Utilities.bytesToString(data));
((Activity) mContext).runOnUiThread(new Runnable() {
public void run() {
usbSerialListener.onDataReceived(data);
}
});
}
@Override
public void onRunError(Exception e) {
//removeTimeOutCallbacks();
usbSerialListener.onErrorReceived("onRunError: " + Utilities.getStackTrace(e));
}
private class SetUsbSerialDriver extends AsyncTask<Integer, Void, Boolean> {
@Override
protected Boolean doInBackground(Integer... params) {
try {
UsbDeviceConnection connection = usbManager.openDevice(serialPort.getDriver().getDevice());
if (connection == null) {
// You probably need to
// callUsbManager.requestPermission(driver.getDevice(),
// ..)
Log.d(TAG, "Opening device failed");
return false;
} else {
try {
serialPort.open(connection);
serialPort.setParameters(params[0], 11, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE);
Log.d(TAG, "Serial device: " + serialPort.getClass().getSimpleName());
return true;
} catch (IOException e) {
Log.d(TAG, "Error setting up device: " + Utilities.getStackTrace(e));
pausedActivity();
serialPort = null;
}
}
} catch (Exception e) {
Log.d(TAG, "Error setting up device: " + Utilities.getStackTrace(e));
pausedActivity();
}
return false;
}
@Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
onDeviceStateChange(result ? ResponseStatus.SUCCESS : ResponseStatus.ERROR);
}
}
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|---|---|
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