Wednesday, 4 May 2016

Android Bluetooth Printing with Actual Printer Device Example

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 like bluetooth open, close or data sent
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;
 
// needed for communication to bluetooth device / network
OutputStream mmOutputStream;
InputStream mmInputStream;
Thread workerThread;
 
byte[] readBuffer;
int readBufferPosition;
volatile boolean stopWorker;



@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
 
    try {
        // more codes will be here
    }catch(Exception e) {
        e.printStackTrace();
    }
}





<?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"
    android:layout_margin="10dp">
 
    <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" />
 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/entry">
 
        <Button
            android:id="@+id/open"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:text="Open" />
 
        <Button
            android:id="@+id/send"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Send" />
 
        <Button
            android:id="@+id/close"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Close" />
    </LinearLayout>
</RelativeLayout>





// we are going 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);
 
// text label and input box
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) {
            ex.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) {
                 
                // RPP300 is the name of the bluetooth printer device
                // we got this name from the list of paired devices
                if (device.getName().equals("RPP300")) {
                    mmDevice = device;
                    break;
                }
            }
        }
 
        myLabel.setText("Bluetooth device found.");
 
    }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 (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
                                    );
 
                                    // specify US-ASCII encoding
                                    final String data = new String(encodedBytes, "US-ASCII");
                                    readBufferPosition = 0;
 
                                    // tell the user data were sent to bluetooth printer device
                                    handler.post(new Runnable() {
                                        public void run() {
                                            myLabel.setText(data);
                                        }
                                    });
 
                                } else {
                                    readBuffer[readBufferPosition++] = b;
                                }
                            }
                        }
                         
                    } catch (IOException ex) {
                        stopWorker = true;
                    }
                     
                }
            }
        });
 
        workerThread.start();
 
    } catch (Exception e) {
        e.printStackTrace();
    }
}





// send data typed by the user to be printed
sendButton.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        try {
            sendData();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
});




// this will send text 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 (Exception e) {
        e.printStackTrace();
    }
}




// close bluetooth connection
closeButton.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        try {
            closeBT();
        } catch (IOException ex) {
            ex.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 (Exception e) {
        e.printStackTrace();
    }
}


    package="com.vinodsonava.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>
 
</manifest>


No comments:

Post a Comment