BLUETOOTH FILE TRANSFER CODING IN JAVA:

MainActivity.java

package com.example.bluetoothdatatransfer;

import java.io.File;

import java.util.List;

import android.bluetooth.BluetoothAdapter;

import android.content.Intent;

import android.content.pm.PackageManager;

import android.content.pm.ResolveInfo;

import android.net.Uri;

import android.os.Bundle;

import android.os.Environment;

import android.support.v7.app.ActionBarActivity;

import android.view.View;

import android.widget.Toast;

public class MainActivity extends ActionBarActivity {

     private static final int DISCOVER_DURATION = 300;

     private static final int REQUEST_BLU = 1;

    

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

    }

    public void sendViaBluetooth(View v) {

   

    BluetoothAdapter btAdapter = BluetoothAdapter.getDefaultAdapter();

   

    if(btAdapter == null) {

           Toast.makeText(this, "Bluetooth is not supported on this device", Toast.LENGTH_LONG).show();

    } else {

           enableBluetooth();

    }

    }

   

    public void enableBluetooth() {

   

    Intent discoveryIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);

   

    discoveryIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, DISCOVER_DURATION);

   

    startActivityForResult(discoveryIntent, REQUEST_BLU);

    }

   

    @Override

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {

   

    if(resultCode == DISCOVER_DURATION && requestCode == REQUEST_BLU) {

          

           Intent intent = new Intent();

           intent.setAction(Intent.ACTION_SEND);

           intent.setType("text/plain");

           File f = new File(Environment.getExternalStorageDirectory(), "ganesh.txt");

           intent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(f));

          

           PackageManager pm = getPackageManager();

           List<ResolveInfo> appsList = pm.queryIntentActivities(intent, 0);

          

           if(appsList.size() > 0) {

                String packageName = null;

                String className = null;

                boolean found = false;

               

                for(ResolveInfo info : appsList) {

                     packageName = info.activityInfo.packageName;

                     if(packageName.equals("com.android.bluetooth")) {

                           className = info.activityInfo.name;

                           found = true;

                           break;

                     }

                }

               

                     if (!found) {

                 Toast.makeText(this, "Bluetooth havn't been found",

                                     Toast.LENGTH_LONG).show();

                     } else {

                   intent.setClassName(packageName, className);

                           startActivity(intent);

                     }

           }

           } else {

                Toast.makeText(this, "Bluetooth is cancelled", Toast.LENGTH_LONG)

                           .show();

           }

    }

}

ACTIVITYMAIN.XML

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context="com.example.bluetoothdatatransfer.MainActivity" >

    <Button

        android:layout_height="wrap_content"

        android:layout_width="wrap_content"

        android:text="Send via Bluetooth"

        android:onClick="sendViaBluetooth"/>

</RelativeLayout>

AndroidManifest.XML

<uses-permission android:name="android.permission.BLUETOOTH"/>

<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>