sl4a/Common/src/com/googlecode/android_scripting/facade/bluetooth/BluetoothDiscoveryHelper.java

/*
 * Copyright (C) 2016 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.googlecode.android_scripting.facade.bluetooth;

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;

import java.util.Set;

import com.googlecode.android_scripting.Log;

public class BluetoothDiscoveryHelper {

  public static interface BluetoothDiscoveryListener {
    public void addBondedDevice(String name, String address);

    public void addDevice(String name, String address);

    public void scanDone();
  }

  private final Context mContext;
  private final BluetoothDiscoveryListener mListener;
  private final BroadcastReceiver mReceiver;

  public BluetoothDiscoveryHelper(Context context, BluetoothDiscoveryListener listener) {
    mContext = context;
    mListener = listener;
    mReceiver = new BluetoothReceiver();
  }

  private class BluetoothReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
      final String action = intent.getAction();

      if (BluetoothDevice.ACTION_FOUND.equals(action)) {
        // Get the BluetoothDevice object from the Intent.
        BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
        Log.d("Found device " + device.getAliasName());
        // If it's already paired, skip it, because it's been listed already.
        if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
          mListener.addDevice(device.getName(), device.getAddress());
        }
      } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
        mListener.scanDone();
      }
    }
  }

  public void startDiscovery() {
    BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

    if (bluetoothAdapter.isDiscovering()) {
      bluetoothAdapter.cancelDiscovery();
    }

    Set<BluetoothDevice> pairedDevices = bluetoothAdapter.getBondedDevices();
    for (BluetoothDevice device : pairedDevices) {
      mListener.addBondedDevice(device.getName(), device.getAddress());
    }

    IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
    filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
    mContext.registerReceiver(mReceiver, filter);

    if (!bluetoothAdapter.isEnabled()) {
      bluetoothAdapter.enable();
    }

    bluetoothAdapter.startDiscovery();
  }

  public void cancel() {
    mContext.unregisterReceiver(mReceiver);
    mListener.scanDone();
  }
}