Develop Reference

Send data to bluetooth printer

I am using SimpleBluetoothLibrary to access my bluetooth printer.now i can search available devices,select bluetooth printer from the list,connect to the printer.those parts are done.but i don't know how to send data to the printer for print job.this is onDeviceConnected method.i've got device address from it.but i want to send data to printer.
#Override
public void onDeviceConnected(BluetoothDevice device) {
//a device is connected so you can now send stuff to it
mTxt.setText("Connection Status:Connected:" + device.getAddress());
Log.d("Mac_Address", device.getAddress());
}

There is a simple example for sending data from Bluetooth.I hope it helps you.
MainActivity.java
package com.example.bluetoothprinter;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.TextView;
import android.widget.EditText;
import android.widget.Button;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends Activity {
// will show the statuses
TextView myLabel;
// will enable user to enter any text to be printed
EditText myTextbox;
// android built in classes for bluetooth operations
BluetoothAdapter mBluetoothAdapter;
BluetoothSocket mmSocket;
BluetoothDevice mmDevice;
OutputStream mmOutputStream;
InputStream mmInputStream;
Thread workerThread;
byte[] readBuffer;
int readBufferPosition;
int counter;
volatile boolean stopWorker;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
// we are goin to have three buttons for specific functions
Button openButton = (Button) findViewById(R.id.open);
Button sendButton = (Button) findViewById(R.id.send);
Button closeButton = (Button) findViewById(R.id.close);
myLabel = (TextView) findViewById(R.id.label);
myTextbox = (EditText) findViewById(R.id.entry);
// open bluetooth connection
openButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
findBT();
openBT();
} catch (IOException ex) {
}
}
});
// send data typed by the user to be printed
sendButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
sendData();
} catch (IOException ex) {
}
}
});
// close bluetooth connection
closeButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
closeBT();
} catch (IOException ex) {
}
}
});
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
// This will find a bluetooth printer device
void findBT() {
try {
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
myLabel.setText("No bluetooth adapter available");
}
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBluetooth = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 0);
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
// MP300 is the name of the bluetooth printer device
if (device.getName().equals("MP300")) {
mmDevice = device;
break;
}
}
}
myLabel.setText("Bluetooth Device Found");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
// Tries to open a connection to the bluetooth printer device
void openBT() throws IOException {
try {
// Standard SerialPortService ID
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
// After opening a connection to bluetooth printer device,
// we have to listen and check if a data were sent to be printed.
void beginListenForData() {
try {
final Handler handler = new Handler();
// This is the ASCII code for a newline character
final byte delimiter = 10;
stopWorker = false;
readBufferPosition = 0;
readBuffer = new byte[1024];
workerThread = new Thread(new Runnable() {
public void run() {
while (!Thread.currentThread().isInterrupted()
&& !stopWorker) {
try {
int bytesAvailable = mmInputStream.available();
if (bytesAvailable > 0) {
byte[] packetBytes = new byte[bytesAvailable];
mmInputStream.read(packetBytes);
for (int i = 0; i < bytesAvailable; i++) {
byte b = packetBytes[i];
if (b == delimiter) {
byte[] encodedBytes = new byte[readBufferPosition];
System.arraycopy(readBuffer, 0,
encodedBytes, 0,
encodedBytes.length);
final String data = new String(
encodedBytes, "US-ASCII");
readBufferPosition = 0;
handler.post(new Runnable() {
public void run() {
myLabel.setText(data);
}
});
} else {
readBuffer[readBufferPosition++] = b;
}
}
}
} catch (IOException ex) {
stopWorker = true;
}
}
}
});
workerThread.start();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* This will send data to be printed by the bluetooth printer
*/
void sendData() throws IOException {
try {
// the text typed by the user
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream.write(msg.getBytes());
// tell the user data were sent
myLabel.setText("Data Sent");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
// Close the connection to bluetooth printer.
void closeBT() throws IOException {
try {
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<TextView
android:id="#+id/label"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Type here:" />
<EditText
android:id="#+id/entry"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#id/label"
android:background="#android:drawable/editbox_background" />
<Button
android:id="#+id/open"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="#id/entry"
android:layout_marginLeft="10dip"
android:text="Open" />
<Button
android:id="#+id/send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#id/open"
android:layout_toLeftOf="#id/open"
android:text="Send" />
<Button
android:id="#+id/close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#id/send"
android:layout_toLeftOf="#id/send"
android:text="Close" />
AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.bluetoothprinter"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<supports-screens android:anyDensity="true" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Result pictures are below:

Bluetooth send a text to other device

i have a simple question:
first, this is all my code:
package com.example.mybluetoothapp;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.UUID;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.Menu;
import android.widget.Toast;
public class MainActivity extends Activity {
List<BluetoothDevice> devices = new ArrayList<BluetoothDevice>();
BroadcastReceiver broadcastReceiver;
BluetoothAdapter bluetoothAdapter;
public UUID serverUuid = UUID.fromString("SERVEUR");
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
Toast.makeText(this, "Votre appareil n'a pas de Bluetooth",
Toast.LENGTH_LONG).show();
finish();
}
if (!bluetoothAdapter.isEnabled()) {
Intent bluetoothIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(bluetoothIntent, 1);
}
Set<BluetoothDevice> pairedDevices = bluetoothAdapter
.getBondedDevices();
if (pairedDevices.size() > 0) {
for (BluetoothDevice bluetoothDevice : pairedDevices) {
devices.add(bluetoothDevice);
}
}
broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
BluetoothDevice device = intent
.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
devices.add(device);
}
}
};
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(broadcastReceiver, filter);
Intent dicoverableIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
dicoverableIntent.putExtra(
BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(dicoverableIntent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
protected void onDestroy() {
unregisterReceiver(broadcastReceiver);
super.onDestroy();
}
private class AcceptThread extends Thread {
BluetoothServerSocket bluetoothServerSocket;
public AcceptThread() {
BluetoothServerSocket serverSocketTmp = null;
try {
serverSocketTmp = bluetoothAdapter
.listenUsingRfcommWithServiceRecord("Bluetooth APP",
serverUuid);
bluetoothServerSocket = serverSocketTmp;
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void run() {
BluetoothSocket socket = null;
while (true) {
try {
socket = bluetoothServerSocket.accept();
} catch (IOException e) {
e.printStackTrace();
}
if (socket != null) {
// TODO: Managed Connection
// TODO: Envoyer Bonjour et Bienvenue
try {
bluetoothServerSocket.close();
break;
} catch (IOException e) {
e.printStackTrace();
}
}
}
super.run();
}
private void cancel() {
try {
bluetoothServerSocket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
private class ConnectThread extends Thread {
BluetoothSocket socket;
BluetoothDevice device;
public ConnectThread(BluetoothDevice device) {
this.device = device;
BluetoothSocket socketTmp = null;
try {
socketTmp = device
.createRfcommSocketToServiceRecord(serverUuid);
socket = socketTmp;
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void run() {
bluetoothAdapter.cancelDiscovery();
try {
socket.connect();
} catch (IOException e) {
try {
socket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
e.printStackTrace();
return;
}
// TODO: Manage connection
super.run();
}
private void cancel() {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
private class ConnectedThread extends Thread {
private BluetoothSocket bluetoothSocket;
InputStream inputStream = null;
OutputStream outputStream = null;
public ConnectedThread(BluetoothSocket socket) {
bluetoothSocket = socket;
InputStream inputStreamTmp = null;
OutputStream outputStreamTmp = null;
try {
inputStreamTmp = bluetoothSocket.getInputStream();
outputStreamTmp = bluetoothSocket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
inputStream = inputStreamTmp;
outputStream = outputStreamTmp;
}
#Override
public void run() {
byte[] buffer = new byte[1024];
int bytes;
while (true) {
try {
bytes = inputStream.read(buffer);
// TODO: Envoyer message à l'affichage
} catch (IOException e) {
e.printStackTrace();
break;
}
}
super.run();
}
public void write(byte[] bytes) {
try {
outputStream.write(bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
public void cancel() {
try {
bluetoothSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
i get this code from a website, so please how i can us it to send a 'hello world' bettween two smartphone ?
please i need help
thank you

Use the ConnectedThread:
How to send any data.
//Code to send text
String text = "Example";
mConnectedThread.write(text.getBytes());
How to receive the sent text (array length is 1024 and 1024 bytes is 1 KB), modify the run() method in ConnectedThread
#Override
public void run() {
byte[] buffer = new byte[1024];
int bytes;
while (true) {
try {
bytes = inputStream.read(buffer);
//Received text is here
String text = new String(buffer, 0, bytes);
Log.d(TAG, text);
} catch (IOException e) {
e.printStackTrace();
break;
}
}
super.run();
}
After checking your code, it seems the threads haven't been started

Error; The application may be doing too much work on its main thread [duplicate]

This question already has answers here:
The application may be doing too much work on its main thread
(21 answers)
Closed 8 years ago.
I don't know why this error keeps popping up. Here is my entire class;
public class MainActivity extends Activity {
// will show the statuses
TextView myLabel;
// will enable user to enter any text to be printed
EditText myTextbox;
// android built in classes for bluetooth operations
BluetoothAdapter mBluetoothAdapter;
BluetoothSocket mmSocket;
BluetoothDevice mmDevice;
OutputStream mmOutputStream;
InputStream mmInputStream;
Thread workerThread;
byte[] readBuffer;
int readBufferPosition;
int counter;
volatile boolean stopWorker;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
// we are goin to have three buttons for specific functions
Button openButton = (Button) findViewById(R.id.open);
Button sendButton = (Button) findViewById(R.id.send);
Button closeButton = (Button) findViewById(R.id.close);
myLabel = (TextView) findViewById(R.id.label);
myTextbox = (EditText) findViewById(R.id.entry);
// open bluetooth connection
openButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
findBT();
openBT();
} catch (IOException ex) {
}
}
});
// send data typed by the user to be printed
sendButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
sendData();
} catch (IOException ex) {
}
}
});
// close bluetooth connection
closeButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
closeBT();
} catch (IOException ex) {
}
}
});
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* This will find a bluetooth printer device
*/
void findBT() {
try {
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
myLabel.setText("No bluetooth adapter available");
}
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBluetooth = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 0);
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
// MP300 is the name of the bluetooth printer device
if (device.getName().equals("Star Micronics")) {
mmDevice = device;
break;
}
}
}
myLabel.setText("Bluetooth Device Found");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* Tries to open a connection to the bluetooth printer device
*/
void openBT() throws IOException {
try {
// Standard SerialPortService ID
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* After opening a connection to bluetooth printer device,
* we have to listen and check if a data were sent to be printed.
*/
void beginListenForData() {
try {
final Handler handler = new Handler();
// This is the ASCII code for a newline character
final byte delimiter = 10;
stopWorker = false;
readBufferPosition = 0;
readBuffer = new byte[1024];
workerThread = new Thread(new Runnable() {
public void run() {
while (!Thread.currentThread().isInterrupted()
&& !stopWorker) {
try {
int bytesAvailable = mmInputStream.available();
if (bytesAvailable > 0) {
byte[] packetBytes = new byte[bytesAvailable];
mmInputStream.read(packetBytes);
for (int i = 0; i < bytesAvailable; i++) {
byte b = packetBytes[i];
if (b == delimiter) {
byte[] encodedBytes = new byte[readBufferPosition];
System.arraycopy(readBuffer, 0,
encodedBytes, 0,
encodedBytes.length);
final String data = new String(
encodedBytes, "US-ASCII");
readBufferPosition = 0;
handler.post(new Runnable() {
public void run() {
myLabel.setText(data);
}
});
} else {
readBuffer[readBufferPosition++] = b;
}
}
}
} catch (IOException ex) {
stopWorker = true;
}
}
}
});
workerThread.start();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* Close the connection to bluetooth printer.
*/
void closeBT() throws IOException {
try {
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* This will send data to be printed by the bluetooth printer
*/
void sendData() throws IOException {
try {
// the text typed by the user
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream.write(msg.getBytes());
// tell the user data were sent
myLabel.setText("Data Sent");
closeBT();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}//End of class
This code snippet is a one class application, which is supposed to print whatever is written into the text field but when I check for paired devices, it gives the error of the title.
Any suggestions why??

This error will mainly arise if you do a heavy network operation over main thread. I mean without using any asynctask or handler in your class you are doing the network operations.
SO use as much handler or asynctask when you are going to make a network call in your application to download, to post something from your device to server etc.

Print Pdf file via Bluetooth Printer Android

In My project Need to print Pdf file Via Bluetooth Printer. I write a code to print via pdf
Its for fine for a Text,
But I want to Print PDF file on Bluetooth printer.
My java Code to Print Text
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv= (ListView) findViewById(R.id.listView1);
// listdata(lv);
try {
// we are goin to have three buttons for specific functions
Button openButton = (Button) findViewById(R.id.open);
Button sendButton = (Button) findViewById(R.id.send);
Button closeButton = (Button) findViewById(R.id.close);
Button btnco= (Button) findViewById(R.id.btnconnect);
btnco.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
try {
findBT();
openBT();
} catch (Exception ex) {
}
}
});
myLabel = (TextView) findViewById(R.id.label);
myTextbox = (EditText) findViewById(R.id.entry);
// open bluetooth connection
openButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
startActivity(new Intent(MainActivity.this,NewAct.class));
}
});
// send data typed by the user to be printed
sendButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
sendData();
} catch (IOException ex) {
}
}
});
// close bluetooth connection
closeButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
closeBT();
} catch (IOException ex) {
}
}
});
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* This will find a bluetooth printer device
*/
void findBT() {
try {
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
myLabel.setText("No bluetooth adapter available");
Toast.makeText(MainActivity.this, "No bluetooth available", Toast.LENGTH_LONG).show();
// startActivity(new Intent(MainActivity.this,NewAct.class));
}
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBluetooth = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 0);
Toast.makeText(this, "OPen", Toast.LENGTH_LONG).show();
//startActivity(new Intent(MainActivity.this,NewAct.class));
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter
.getBondedDevices();
if (pairedDevices.size() > 0) {
for (BluetoothDevice device : pairedDevices) {
// MP300 is the name of the bluetooth printer device
if (device.getName().equals(NewAct.printer)) {
//openBT();
mmDevice = device;
break;
}
else {
}
}
}
{
myLabel.setText("Bluetooth Device Found");
try {
// Standard SerialPortService ID
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
} catch (NullPointerException e) {
e.printStackTrace();
}
}
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* Tries to open a connection to the bluetooth printer device
*/
void openBT() throws IOException {
try {
// Standard SerialPortService ID
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* After opening a connection to bluetooth printer device,
* we have to listen and check if a data were sent to be printed.
*/
void beginListenForData() {
try {
final Handler handler = new Handler();
// This is the ASCII code for a newline character
final byte delimiter = 10;
stopWorker = false;
readBufferPosition = 0;
readBuffer = new byte[1024];
workerThread = new Thread(new Runnable() {
public void run() {
while (!Thread.currentThread().isInterrupted()
&& !stopWorker) {
try {
int bytesAvailable = mmInputStream.available();
if (bytesAvailable > 0) {
byte[] packetBytes = new byte[bytesAvailable];
mmInputStream.read(packetBytes);
for (int i = 0; i < bytesAvailable; i++) {
byte b = packetBytes[i];
if (b == delimiter) {
byte[] encodedBytes = new byte[readBufferPosition];
System.arraycopy(readBuffer, 0,
encodedBytes, 0,
encodedBytes.length);
final String data = new String(
encodedBytes, "US-ASCII");
readBufferPosition = 0;
handler.post(new Runnable() {
public void run() {
myLabel.setText(data);
}
});
} else {
readBuffer[readBufferPosition++] = b;
}
}
}
} catch (IOException ex) {
stopWorker = true;
}
}
}
});
workerThread.start();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* This will send data to be printed by the bluetooth printer
*/
void sendData() throws IOException {
try {
// the text typed by the user
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream.write(msg.getBytes());
// tell the user data were sent
myLabel.setText("Data Sent");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* Close the connection to bluetooth printer.
*/
void closeBT() throws IOException {
try {
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
public void listdata(ListView lv){
try{
pairedDevices = mBluetoothAdapter.getBondedDevices();
ArrayList<String> list = new ArrayList<String>();
for(BluetoothDevice bt : pairedDevices)
list.add(bt.getName());
Toast.makeText(getApplicationContext(),"Showing Paired Devices",
Toast.LENGTH_SHORT).show();
#SuppressWarnings("unchecked")
final ArrayAdapter<String> adapter = new ArrayAdapter<String>
(this,android.R.layout.simple_list_item_1, list);
lv.setAdapter(adapter);
}catch(Exception e)
{
Toast.makeText(this, "error"+e, Toast.LENGTH_LONG).show();
}
}
I don't have Idea How to Pass Pdf file for print to Bluetooth Printer
Please Help Me How i can do this
Thanks In Advance.

You could try getting bytes from a pdf file & send them to printer as follows:
/*
* This will send data to be printed by the bluetooth printer
*/
void sendData() throws IOException {
try {
// the text typed by the user
//String msg = myTextbox.getText().toString();
//msg += "\n";
InputStream is = this.openFileInput("filename.pdf"); // Where this is Activity
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte[] b = new byte[1024];
while ((int bytesRead = is.read(b)) != -1) {
bos.write(b, 0, bytesRead);
}
byte[] bytes = bos.toByteArray();
byte[] printformat = { 27, 33, 0 }; //try adding this print format
mmOutputStream.write(printformat);
mmOutputStream.write(bytes);
// tell the user data were sent
myLabel.setText("Data Sent");
closeBT();
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
You will need to add following permissions in your Android Manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

Any application print a pdf has some library to decode pdf.
Of course you can send only a text to your printer.
If you want to print directly pdf you need your own library to do that.
For android i always use mupdf, very powerfuf lib and open source.
look at stackoverflow how to install step-by-step Integrate MuPDF Reader in an app
after you done run a full demo project from https://github.com/derek-watson/mupdf
list on directory (mupdf/platform/android/)
It will run main activity ChoosePDFActivity.java after you picked up pdf from your device it will showing, then main top bar have print button (PrintDialogActivity.java to print on google cloud print) change code here to send stream to your printer
Hope this help!!!

Most bluetooth printers do not support printing PDFs out of the box.
What you need to do is use the Android printer framework or any other library/class like PDFRenderer to convert the PDF pages to images and send those images to the printer with an emulation the printer understands (ex ZPL, CPCL, PCL-3 etc.)

You could try to open the pdf using an Android intent if it's possible to print it from another app (maybe the manufacturer's own?)
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(file), "application/pdf");
c.startActivity(intent);

You can make the app first convert PDF into a Bitmap, silently, then print the Bitmap via the thermal printer.

Android Bluetooth reading btrs232 adapter

I am writing a simple communication program between Android device 2.2 and Bluetooth RS232 adapter.
I managed to connect and send text successfully, but when reading from the adapter the application crashes.
I do appreciate any help and advice.
Thanks
main.xml file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:id="#+id/text_messages"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/hello"
/>
<Button android:text="Button" android:id="#+id/button_listen"
android:layout_width="wrap_content" android:layout_height="wrap_content">
</Button>
</LinearLayout>
MyActivity.java
package com.epostech.bt232test;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Set;
import java.util.UUID;
import java.util.Vector;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
//import android.widget.ArrayAdapter;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MyActivity extends Activity {
private static final int REQUEST_ENABLE_BT = 3;
private String mac = "";
private static final UUID MY_UUID_INSECURE = UUID
.fromString("00001101-0000-1000-8000-00805F9B34FB");
private BluetoothSocket clientSocket;
// private ArrayAdapter<String> mArrayAdapter;
private Vector<String> deviceMacs = new Vector<String>();
private Vector<String> deviceNames = new Vector<String>();
#SuppressWarnings("unused")
private Handler handler = new Handler();
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
final TextView messageText = (TextView) findViewById(R.id.text_messages);
// messageText.setVisibility(View.VISIBLE);
setContentView(R.layout.main);
Button listenButton = (Button) findViewById(R.id.button_listen);
listenButton.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
// closeSocket();
sendMessage(clientSocket, "P\r\n");
// testing(mac);
}
});
BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();
String toastText = "";
/*
* if(bluetooth.isEnabled()){ String address= bluetooth.getAddress();
* String name=bluetooth.getName(); toastText=name+" : "+address;
*
* } else
*/
if (!bluetooth.isEnabled()) {
toastText = "Bluetooth is not Enabled!";
Toast.makeText(this, toastText, Toast.LENGTH_LONG).show();
Intent enableBtIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
Toast.makeText(this, "BlueTooth Enabled", Toast.LENGTH_LONG).show();
}
Set<BluetoothDevice> pairedDevices = bluetooth.getBondedDevices();
// Toast.makeText(this,"Size="+pairedDevices.size(),
// Toast.LENGTH_LONG).show();
// If there are paired devices
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
// Add the name and address to an array adapter to show in a
// ListView
deviceMacs.add(device.getAddress());
deviceNames.add(device.getName());
}
} else {
Toast.makeText(this, "Size=" + pairedDevices.size(),
Toast.LENGTH_LONG).show();
}
mac = deviceMacs.get(deviceNames.indexOf("M7705B0125"));
BluetoothDevice device = bluetooth.getRemoteDevice(mac);
try {
clientSocket = device
.createRfcommSocketToServiceRecord(MY_UUID_INSECURE);
clientSocket.connect();
// TODO Transfer data using the Bluetooth Socket
} catch (IOException e) {
Log.d("BLUETOOTH", e.getMessage());
}
BluetoothSocketListener bsl = new BluetoothSocketListener(clientSocket, handler, messageText);
Thread messageListener = new Thread(bsl);
messageListener.start();
}
private void closeSocket() {
try {
clientSocket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void sendMessage(BluetoothSocket socket, String msg) {
OutputStream outStream;
try {
outStream = socket.getOutputStream();
byte[] byteString = msg.getBytes();
byteString[byteString.length - 1] = 0;
outStream.write(byteString);
} catch (IOException e) {
Log.d("BLUETOOTH_COMMS", e.getMessage());
}
}
// The Handler that gets information back from the BluetoothChatService
#Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
closeSocket();
}
}
BluetoothSocketListener.java
package com.epostech.bt232test;
import java.io.IOException;
import java.io.InputStream;
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
import android.util.Log;
import android.widget.TextView;
public class BluetoothSocketListener implements Runnable {
private BluetoothSocket socket;
private TextView textView;
private Handler handler;
public BluetoothSocketListener(BluetoothSocket socket,
Handler handler, TextView textView) {
this.socket = socket;
this.textView = textView;
this.handler = handler;
}
public void run() {
byte[] buffer = new byte[1024];
int bytes;
InputStream instream=null;
try {
instream = socket.getInputStream();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
String message = "";
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
bytes = instream.read(buffer);
message = message + new String(buffer, 0, bytes);
// Send the obtained bytes to the UI Activity
handler.post(new MessagePoster(textView, message));
} catch (IOException e) {
break;
}
}
}
/*
public void run() {
int bufferSize = 256;
byte[] buffer = new byte[bufferSize];
try {
InputStream instream = socket.getInputStream();
int bytesRead = -1;
String message = "";
while (true) {
message = "";
bytesRead = instream.read(buffer);
if (bytesRead != -1) {
while ((bytesRead==bufferSize)&&(buffer[bufferSize-1] != 0)) {
message = message + new String(buffer, 0, bytesRead);
bytesRead = instream.read(buffer);
}
message = message + new String(buffer, 0, bytesRead - 1);
handler.post(new MessagePoster(textView, message));
//socket.getInputStream();
}
}
} catch (IOException e) {
Log.d("BLUETOOTH_COMMS", e.getMessage());
}
}
*/
}
MessagePoster.java
package com.epostech.bt232test;
import android.widget.TextView;
public class MessagePoster implements Runnable {
private TextView textView;
private String message;
public MessagePoster(TextView textView, String message) {
this.textView = textView;
this.message = message;
}
public void run() {
textView.setText(message);
}
}

Problem solved
I can read and write to RS232 and display the result on TextView using Handler to communicate with UI and Socket thread.
It was hard excersise but I did it with simple program as follows:
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// messageText.setVisibility(View.VISIBLE);
setContentView(R.layout.main);
messageText = (TextView) findViewById(R.id.text_messages);
Button listenButton = (Button) findViewById(R.id.button_listen);
listenButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// closeSocket();
sendData(clientSocket, "P\r\n");
}
});
BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();
String toastText = "";
/*
* if(bluetooth.isEnabled()){ String address= bluetooth.getAddress();
* String name=bluetooth.getName(); toastText=name+" : "+address;
*
* } else
*/
if (!bluetooth.isEnabled()) {
toastText = "Bluetooth is not Enabled!";
Toast.makeText(this, toastText, Toast.LENGTH_LONG).show();
Intent enableBtIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
Toast.makeText(this, "BlueTooth Enabled", Toast.LENGTH_LONG).show();
}
Set<BluetoothDevice> pairedDevices = bluetooth.getBondedDevices();
// Toast.makeText(this,"Size="+pairedDevices.size(),
// Toast.LENGTH_LONG).show();
// If there are paired devices
if (pairedDevices.size() > 0) {
// Loop through paired devices
for (BluetoothDevice device : pairedDevices) {
// Add the name and address to an array adapter to show in a
// ListView
deviceMacs.add(device.getAddress());
deviceNames.add(device.getName());
}
} else {
Toast.makeText(this, "Size=" + pairedDevices.size(),
Toast.LENGTH_LONG).show();
}
mac = deviceMacs.get(deviceNames.indexOf("M7705B0125"));
BluetoothDevice device = bluetooth.getRemoteDevice(mac);
try {
clientSocket = device
.createRfcommSocketToServiceRecord(MY_UUID_INSECURE);
clientSocket.connect();
// TODO Transfer data using the Bluetooth Socket
} catch (IOException e) {
Log.d("BLUETOOTH", e.getMessage());
}
BluetoothSocketListener bsl = new BluetoothSocketListener(clientSocket,
handler, messageText);
Thread messageListener = new Thread(bsl);
messageListener.start();
}// end of onCreate()code
// The Handler that gets information back from the BluetoothChatService
private final Handler mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
String readMessage = new String(readBuf, 0, msg.arg1);
messageText.setText(readMessage);
}
};
private void closeSocket() {
try {
clientSocket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
// The Handler that gets information back from the BluetoothChatService
#Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
closeSocket();
}
private class BluetoothSocketListener implements Runnable {
private BluetoothSocket socket;
private TextView textView;
private Handler handler;
private InputStream inStream;
private OutputStream outStream;
public BluetoothSocketListener(BluetoothSocket socket, Handler handler,
TextView textView) {
this.socket = socket;
this.textView = textView;
this.handler = handler;
try {
outStream = socket.getOutputStream();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void run() {
int bufferSize = 1024;
byte[] buffer = new byte[bufferSize];
int data;
try {
inStream = socket.getInputStream();
int bytesRead = -1;
String message = "";
// Keep listening to the InputStream while connected
int len= 0;
while (true) {
try {
// Read from the InputStream
bytesRead = inStream.read(buffer);
message= message+new String(buffer,0,bytesRead);
// Send the obtained bytes to the UI Activity
byte[] byteString = message .getBytes();
byteString[byteString.length - 1] = 0;
outStream.write(byteString);
handler.post(new MessagePoster(textView,"Text="+ message+" "+"Bytes read="+bytesRead));
} catch (IOException e) {
Log.e(TAG, "disconnected", e);
break;
}
}
} catch (IOException e) {
Log.d("BLUETOOTH_COMMS", e.getMessage());
}
}
}
private class MessagePoster implements Runnable {
private TextView textView;
private String message;
public MessagePoster(TextView textView, String message) {
this.textView = textView;
this.message = message;
}
public void run() {
textView.setText(message);
}
}
private void sendData(BluetoothSocket socket, String msg) {
OutputStream outStream;
try {
outStream = socket.getOutputStream();
byte[] byteString = msg.getBytes();
//byteString[byteString.length - 1] = 0;
outStream.write(byteString);
} catch (IOException e) {
Log.d("BLUETOOTH_COMMS", e.getMessage());
}
}
}

Dont forget to add the permission to the manifest
<uses-permission
android:name="android.permission.BLUETOOTH" />

I discovered one thing using a serial to BT adapter hooked to a microcontroler.
Often, the data sent to the serial port is a string ended by [].
I used a serial to bluetooth adapter ine one of my projects, sending data lines ended by a and found that handling data with a Scanner rather than a standard buffer really works better.
Example of the Bluetooth Chat modified:
Scanner scan = new Scanner(new InputStreamReader(mmInStream));
String line;
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
//Send the obtained bytes to the UI Activity
line = scan.next();
mHandler.obtainMessage(CalibrationS2PActivity.MESSAGE_READ, line.length(), -1, line).sendToTarget();
} catch (Exception e) {
Log.e(TAG, "disconnected", e);
connectionLost();
break;
}
}