蓝牙4.0 简单使用

1.需要的权限：

 <uses-feature android:name="android.hardware.bluetooth_le" android:required="true"/>
    <uses-permission android:name="android.permission.BLUETOOTH"/>
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

2.

package com.hmsoft.bluetooth.le;

import android.app.Activity;
import android.app.ListActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothManager;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;

import com.example.bluetooth.le.R;

/**
 * Activity for scanning and displaying available Bluetooth LE devices.
 */
public class DeviceScanActivity extends ListActivity {
    private LeDeviceListAdapter mLeDeviceListAdapter;
    private BluetoothAdapter mBluetoothAdapter;
    private boolean mScanning;

    private static final int REQUEST_ENABLE_BT = 1;
    // Stops scanning after 10 seconds.
    private static final long SCAN_PERIOD = 10000;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getActionBar().setTitle(R.string.title_devices);

        // Use this check to determine whether BLE is supported on the device.  Then you can
        // selectively disable BLE-related features.
        if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
            Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
            finish();
        }

        // Initializes a Bluetooth adapter.  For API level 18 and above, get a reference to
        // BluetoothAdapter through BluetoothManager.
        final BluetoothManager bluetoothManager =
                (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
        mBluetoothAdapter = bluetoothManager.getAdapter();

        // Checks if Bluetooth is supported on the device.
        if (mBluetoothAdapter == null) {
            Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
            finish();
            return;
        }
        
        //Initializes list view adapter.
        mLeDeviceListAdapter = new LeDeviceListAdapter();
        setListAdapter(mLeDeviceListAdapter);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        if (!mScanning) {
            menu.findItem(R.id.menu_stop).setVisible(false);
            menu.findItem(R.id.menu_scan).setVisible(true);
            menu.findItem(R.id.menu_refresh).setActionView(null);
        } else {
            menu.findItem(R.id.menu_stop).setVisible(true);
            menu.findItem(R.id.menu_scan).setVisible(false);
            menu.findItem(R.id.menu_refresh).setActionView(
                    R.layout.actionbar_indeterminate_progress);
        }
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.menu_scan:
                mLeDeviceListAdapter.clear();
                scanLeDevice(true);
                break;
            case R.id.menu_stop:
                scanLeDevice(false);
                break;
        }
        return true;
    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // User chose not to enable Bluetooth.
        if (requestCode == REQUEST_ENABLE_BT && resultCode == Activity.RESULT_CANCELED) {
            finish();
            return;
        }
        super.onActivityResult(requestCode, resultCode, data);
    }
    
    @Override
    protected void onResume() {
        super.onResume();

        // Ensures Bluetooth is enabled on the device.  If Bluetooth is not currently enabled,
        // fire an intent to display a dialog asking the user to grant permission to enable it.
        /*
        if (!mBluetoothAdapter.isEnabled()) {
            if (!mBluetoothAdapter.isEnabled()) {
                Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
            }
        }
        */
    }

    @Override
    protected void onPause() {
        super.onPause();
        scanLeDevice(false);
        //mLeDeviceListAdapter.clear();
    }

    //打开连接界面
    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
        if (device == null) return;
        final Intent intent = new Intent(this, DeviceControlActivity.class);
        intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_NAME, device.getName());
        intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_ADDRESS, device.getAddress());
        if (mScanning) {
            mBluetoothAdapter.stopLeScan(mLeScanCallback);
            mScanning = false;
        }
        startActivity(intent);
    }

    private void scanLeDevice(final boolean enable) {
        if (enable) {
            // Stops scanning after a pre-defined scan period.
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    if(mScanning)
                    {
                        mScanning = false;
                        mBluetoothAdapter.stopLeScan(mLeScanCallback);
                        invalidateOptionsMenu();
                    }
                }
            }, SCAN_PERIOD);

            mScanning = true;
            //F000E0FF-0451-4000-B000-000000000000
            mLeDeviceListAdapter.clear();
            mHandler.sendEmptyMessage(1);
            mBluetoothAdapter.startLeScan(mLeScanCallback);
        } else {
            mScanning = false;
            mBluetoothAdapter.stopLeScan(mLeScanCallback);
        }
        invalidateOptionsMenu();
    }
    
    private static char findHex(byte b) {    
        int t = new Byte(b).intValue();    
        t = t < 0 ? t + 16 : t;    
          
        if ((0 <= t) &&(t <= 9)) {    
        return (char)(t + '0');    
        }    
          
        return (char)(t - 10 + 'A');    
        }  
    
    public static String ByteToString(byte[] bytes) {
          StringBuffer sb = new StringBuffer();
          //for (int i = 0; i < bytes.length && bytes[i] != (byte) 0; i++) {
          for (int i = 0; i < bytes.length; i++) {
           //sb.append((char) (bytes[i]));
           sb.append(findHex((byte)((bytes[i] & 0xf0) >> 4)));
           sb.append(findHex((byte)(bytes[i] & 0x0f)));
           
          }
          return sb.toString();
         }

    // Adapter for holding devices found through scanning.
    private class LeDeviceListAdapter extends BaseAdapter {
        private ArrayList<BluetoothDevice> mLeDevices;
        private LayoutInflater mInflator;

        public LeDeviceListAdapter() {
            super();
            mLeDevices = new ArrayList<BluetoothDevice>();
            mInflator = DeviceScanActivity.this.getLayoutInflater();
        }

        public void addDevice(BluetoothDevice device) {
            if(!mLeDevices.contains(device)) {
                mLeDevices.add(device);
            }
        }

        public BluetoothDevice getDevice(int position) {
            return mLeDevices.get(position);
        }
        
        public void clear() {
            mLeDevices.clear();
        }

        @Override
        public int getCount() {
            return mLeDevices.size();
        }

        @Override
        public Object getItem(int i) {
            return mLeDevices.get(i);
        }

        @Override
        public long getItemId(int i) {
            return i;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            ViewHolder viewHolder;
            // General ListView optimization code.
            if (view == null) {
                view = mInflator.inflate(R.layout.listitem_device, null);
                viewHolder = new ViewHolder();
                viewHolder.deviceAddress = (TextView) view.findViewById(R.id.device_address);
                viewHolder.deviceName = (TextView) view.findViewById(R.id.device_name);
                view.setTag(viewHolder);
            } else {
                viewHolder = (ViewHolder) view.getTag();
            }

            BluetoothDevice device = mLeDevices.get(i);
            final String deviceName = device.getName();
            if (deviceName != null && deviceName.length() > 0)
                viewHolder.deviceName.setText(deviceName);
            else
                viewHolder.deviceName.setText(R.string.unknown_device);
            
            viewHolder.deviceAddress.setText(device.getAddress());

            return view;
        }
    }

    // Device scan callback.
    private BluetoothAdapter.LeScanCallback mLeScanCallback =
            new BluetoothAdapter.LeScanCallback() {

        @Override
        public void onLeScan(final BluetoothDevice device, final int rssi, final byte[] scanRecord) {
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    mLeDeviceListAdapter.addDevice(device);
                    mHandler.sendEmptyMessage(1);
                }
            });
        }
    };

    static class ViewHolder {
        TextView deviceName;
        TextView deviceAddress;
    }
    
    // Hander
    public final Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
            case 1: // Notify change
                mLeDeviceListAdapter.notifyDataSetChanged();
                break;
            }
        }
    };
}

3.

package com.hmsoft.bluetooth.le;

import com.example.bluetooth.le.R;

import android.app.Activity;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ScrollView;
import android.widget.TextView;
import android.widget.Toast;


/**
 * For a given BLE device, this Activity provides the user interface to connect, display data,
 * and display GATT services and characteristics supported by the device.  The Activity
 * communicates with {@code BluetoothLeService}, which in turn interacts with the
 * Bluetooth LE API.
 */
public class DeviceControlActivity extends Activity {
    private final static String TAG = DeviceControlActivity.class.getSimpleName();

    public static final String EXTRAS_DEVICE_NAME = "DEVICE_NAME";
    public static final String EXTRAS_DEVICE_ADDRESS = "DEVICE_ADDRESS";

    private TextView mDataField;
    private String mDeviceName;
    private String mDeviceAddress;
    private BluetoothLeService mBluetoothLeService;
    private boolean mConnected = false;
    
    EditText edtSend;
    ScrollView svResult;
    Button btnSend;

    // Code to manage Service lifecycle.
    private final ServiceConnection mServiceConnection = new ServiceConnection() {

        @Override
        public void onServiceConnected(ComponentName componentName, IBinder service) {
            mBluetoothLeService = ((BluetoothLeService.LocalBinder) service).getService();
            if (!mBluetoothLeService.initialize()) {
                Log.e(TAG, "Unable to initialize Bluetooth");
                finish();
            }
            
            Log.e(TAG, "mBluetoothLeService is okay");
            // Automatically connects to the device upon successful start-up initialization.
            //mBluetoothLeService.connect(mDeviceAddress);
        }

        @Override
        public void onServiceDisconnected(ComponentName componentName) {
            mBluetoothLeService = null;
        }
    };

    // Handles various events fired by the Service.
    // ACTION_GATT_CONNECTED: connected to a GATT server.
    // ACTION_GATT_DISCONNECTED: disconnected from a GATT server.
    // ACTION_GATT_SERVICES_DISCOVERED: discovered GATT services.
    // ACTION_DATA_AVAILABLE: received data from the device.  This can be a result of read
    //                        or notification operations.
    private final BroadcastReceiver mGattUpdateReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            final String action = intent.getAction();
            if (BluetoothLeService.ACTION_GATT_CONNECTED.equals(action)) {  //连接成功
                Log.e(TAG, "Only gatt, just wait");
            } else if (BluetoothLeService.ACTION_GATT_DISCONNECTED.equals(action)) { //断开连接
                mConnected = false;
                invalidateOptionsMenu();
                btnSend.setEnabled(false);
                clearUI();
            }else if(BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED.equals(action)) //可以开始干活了
            {
                mConnected = true;
                mDataField.setText("");
                ShowDialog();
                btnSend.setEnabled(true);
                Log.e(TAG, "In what we need");
                invalidateOptionsMenu();
            }else if (BluetoothLeService.ACTION_DATA_AVAILABLE.equals(action)) { //收到数据
                Log.e(TAG, "RECV DATA");
                String data = intent.getStringExtra(BluetoothLeService.EXTRA_DATA);
                if (data != null) {
                    if (mDataField.length() > 500)
                        mDataField.setText("");
                    mDataField.append(data); 
                    svResult.post(new Runnable() {
                        public void run() {
                            svResult.fullScroll(ScrollView.FOCUS_DOWN);
                        }
                    });
                }
            }
        }
    };

    private void clearUI() {
        mDataField.setText(R.string.no_data);
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {                                        //初始化
        super.onCreate(savedInstanceState);
        setContentView(R.layout.gatt_services_characteristics);

        final Intent intent = getIntent();
        mDeviceName = intent.getStringExtra(EXTRAS_DEVICE_NAME);
        mDeviceAddress = intent.getStringExtra(EXTRAS_DEVICE_ADDRESS);

        // Sets up UI references.
        mDataField = (TextView) findViewById(R.id.data_value);
        edtSend = (EditText) this.findViewById(R.id.edtSend);
        edtSend.setText("www.jnhuamao.cn");
        svResult = (ScrollView) this.findViewById(R.id.svResult);
        
        btnSend = (Button) this.findViewById(R.id.btnSend);
        btnSend.setOnClickListener(new ClickEvent());
        btnSend.setEnabled(false);

        getActionBar().setTitle(mDeviceName);
        getActionBar().setDisplayHomeAsUpEnabled(true);
        Intent gattServiceIntent = new Intent(this, BluetoothLeService.class);
        Log.d(TAG, "Try to bindService=" + bindService(gattServiceIntent, mServiceConnection, BIND_AUTO_CREATE));
        
        registerReceiver(mGattUpdateReceiver, makeGattUpdateIntentFilter());
    }

    @Override
    protected void onResume() {
        super.onResume();
        /*registerReceiver(mGattUpdateReceiver, makeGattUpdateIntentFilter());
        if (mBluetoothLeService != null) {
            final boolean result = mBluetoothLeService.connect(mDeviceAddress);
            Log.d(TAG, "Connect request result=" + result);
        }*/
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(mGattUpdateReceiver);
        unbindService(mServiceConnection);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        //this.unregisterReceiver(mGattUpdateReceiver);
        //unbindService(mServiceConnection);
        if(mBluetoothLeService != null)
        {
            mBluetoothLeService.close();
            mBluetoothLeService = null;
        }
        Log.d(TAG, "We are in destroy");
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.gatt_services, menu);
        if (mConnected) {
            menu.findItem(R.id.menu_connect).setVisible(false);
            menu.findItem(R.id.menu_disconnect).setVisible(true);
        } else {
            menu.findItem(R.id.menu_connect).setVisible(true);
            menu.findItem(R.id.menu_disconnect).setVisible(false);
        }
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {                              //点击按钮
        switch(item.getItemId()) {
            case R.id.menu_connect:
                mBluetoothLeService.connect(mDeviceAddress);
                return true;
            case R.id.menu_disconnect:
                mBluetoothLeService.disconnect();
                return true;
            case android.R.id.home:
                if(mConnected)
                {
                    mBluetoothLeService.disconnect();
                    mConnected = false;
                }
                onBackPressed();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }
    
    private void ShowDialog()
    {
        Toast.makeText(this, "连接成功，现在可以正常通信！", Toast.LENGTH_SHORT).show();
    }

 // 按钮事件
    class ClickEvent implements View.OnClickListener {
        @Override
        public void onClick(View v) {
            if (v == btnSend) {
                if(!mConnected) return;
                
                if (edtSend.length() < 1) {
                    Toast.makeText(DeviceControlActivity.this, "请输入要发送的内容", Toast.LENGTH_SHORT).show();
                    return;
                }
                mBluetoothLeService.WriteValue(edtSend.getText().toString());
                
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                if(imm.isActive())
                    imm.hideSoftInputFromWindow(edtSend.getWindowToken(), 0);
                //todo Send data
            }
        }

    }
    
    private static IntentFilter makeGattUpdateIntentFilter() {                        //注册接收的事件
        final IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(BluetoothLeService.ACTION_GATT_CONNECTED);
        intentFilter.addAction(BluetoothLeService.ACTION_GATT_DISCONNECTED);
        intentFilter.addAction(BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED);
        intentFilter.addAction(BluetoothLeService.ACTION_DATA_AVAILABLE);
        intentFilter.addAction(BluetoothDevice.ACTION_UUID);
        return intentFilter;
    }
}

4.

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * 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.hmsoft.bluetooth.le;

import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattDescriptor;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;

import java.util.List;
import java.util.UUID;

/**
 * Service for managing connection and data communication with a GATT server hosted on a
 * given Bluetooth LE device.
 */
public class BluetoothLeService extends Service {
    private final static String TAG = BluetoothLeService.class.getSimpleName();

    private BluetoothManager mBluetoothManager;
    private BluetoothAdapter mBluetoothAdapter;
    private BluetoothGatt mBluetoothGatt;

    public final static String ACTION_GATT_CONNECTED =
            "com.example.bluetooth.le.ACTION_GATT_CONNECTED";
    public final static String ACTION_GATT_DISCONNECTED =
            "com.example.bluetooth.le.ACTION_GATT_DISCONNECTED";
    public final static String ACTION_GATT_SERVICES_DISCOVERED =
            "com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED";
    public final static String ACTION_DATA_AVAILABLE =
            "com.example.bluetooth.le.ACTION_DATA_AVAILABLE";
    public final static String EXTRA_DATA =
            "com.example.bluetooth.le.EXTRA_DATA";

    public final static UUID UUID_NOTIFY =
            UUID.fromString("0000ffe1-0000-1000-8000-00805f9b34fb");
    public final static UUID UUID_SERVICE =
        UUID.fromString("0000ffe0-0000-1000-8000-00805f9b34fb");
    
    public BluetoothGattCharacteristic mNotifyCharacteristic;
    
    public void WriteValue(String strValue)
    {
        mNotifyCharacteristic.setValue(strValue.getBytes());
        mBluetoothGatt.writeCharacteristic(mNotifyCharacteristic);
    }
    
    public void findService(List<BluetoothGattService> gattServices)
    {
        Log.i(TAG, "Count is:" + gattServices.size());
        for (BluetoothGattService gattService : gattServices) 
        {
            Log.i(TAG, gattService.getUuid().toString());
            Log.i(TAG, UUID_SERVICE.toString());
            if(gattService.getUuid().toString().equalsIgnoreCase(UUID_SERVICE.toString()))
            {
                List<BluetoothGattCharacteristic> gattCharacteristics =
                    gattService.getCharacteristics();
                Log.i(TAG, "Count is:" + gattCharacteristics.size());
                for (BluetoothGattCharacteristic gattCharacteristic :
                    gattCharacteristics) 
                {
                    if(gattCharacteristic.getUuid().toString().equalsIgnoreCase(UUID_NOTIFY.toString()))
                    {
                        Log.i(TAG, gattCharacteristic.getUuid().toString());
                        Log.i(TAG, UUID_NOTIFY.toString());
                        mNotifyCharacteristic = gattCharacteristic;
                        setCharacteristicNotification(gattCharacteristic, true);
                        broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
                        return;
                    }
                }
            }
        }
    }

    // Implements callback methods for GATT events that the app cares about.  For example,
    // connection change and services discovered.
    private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
        @Override
        public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
            String intentAction;
            Log.i(TAG, "oldStatus=" + status + " NewStates=" + newState);
            if(status == BluetoothGatt.GATT_SUCCESS)
            {
            
            if (newState == BluetoothProfile.STATE_CONNECTED) {
                intentAction = ACTION_GATT_CONNECTED;
                
                broadcastUpdate(intentAction);
                Log.i(TAG, "Connected to GATT server.");
                // Attempts to discover services after successful connection.
                Log.i(TAG, "Attempting to start service discovery:" +
                        mBluetoothGatt.discoverServices());
            } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
                intentAction = ACTION_GATT_DISCONNECTED;
                mBluetoothGatt.close();
                mBluetoothGatt = null;
                Log.i(TAG, "Disconnected from GATT server.");
                broadcastUpdate(intentAction);
            }
            }
        }

        @Override
        public void onServicesDiscovered(BluetoothGatt gatt, int status) {
            if (status == BluetoothGatt.GATT_SUCCESS) {
                Log.w(TAG, "onServicesDiscovered received: " + status);
                findService(gatt.getServices());
            } else {
                if(mBluetoothGatt.getDevice().getUuids() == null)
                Log.w(TAG, "onServicesDiscovered received: " + status);
            }
        }

        @Override
        public void onCharacteristicRead(BluetoothGatt gatt,
                                         BluetoothGattCharacteristic characteristic,
                                         int status) {
            if (status == BluetoothGatt.GATT_SUCCESS) {
                broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
            }
        }

        @Override
        public void onCharacteristicChanged(BluetoothGatt gatt,
                                            BluetoothGattCharacteristic characteristic) {
            broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
            Log.e(TAG, "OnCharacteristicWrite");
        }
        
        @Override
        public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic,
                                        int status)
        {
            Log.e(TAG, "OnCharacteristicWrite");
        }
        
        @Override
        public void onDescriptorRead(BluetoothGatt gatt,
                                         BluetoothGattDescriptor bd,
                                         int status) {
            Log.e(TAG, "onDescriptorRead");
        }
        
        @Override
        public void onDescriptorWrite(BluetoothGatt gatt,
                                         BluetoothGattDescriptor bd,
                                         int status) {
            Log.e(TAG, "onDescriptorWrite");
        }
        
        @Override
        public void onReadRemoteRssi(BluetoothGatt gatt, int a, int b)
        {
            Log.e(TAG, "onReadRemoteRssi");
        }
        
        @Override
        public void onReliableWriteCompleted(BluetoothGatt gatt, int a)
        {
            Log.e(TAG, "onReliableWriteCompleted");
        }
        
    };

    private void broadcastUpdate(final String action) {
        final Intent intent = new Intent(action);
        sendBroadcast(intent);
    }

    private void broadcastUpdate(final String action,
                                 final BluetoothGattCharacteristic characteristic) {
        final Intent intent = new Intent(action);

        // This is special handling for the Heart Rate Measurement profile.  Data parsing is
        // carried out as per profile specifications:
        // http://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.heart_rate_measurement.xml
            // For all other profiles, writes the data formatted in HEX.
        final byte[] data = characteristic.getValue();
        if (data != null && data.length > 0) {
            //final StringBuilder stringBuilder = new StringBuilder(data.length);
            //for(byte byteChar : data)
            //    stringBuilder.append(String.format("%02X ", byteChar));
            //intent.putExtra(EXTRA_DATA, new String(data) + "\n" + stringBuilder.toString());
            intent.putExtra(EXTRA_DATA, new String(data));
        }
        sendBroadcast(intent);
    }

    public class LocalBinder extends Binder {
        BluetoothLeService getService() {
            return BluetoothLeService.this;
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        return mBinder;
    }

    @Override
    public boolean onUnbind(Intent intent) {
        // After using a given device, you should make sure that BluetoothGatt.close() is called
        // such that resources are cleaned up properly.  In this particular example, close() is
        // invoked when the UI is disconnected from the Service.
        close();
        return super.onUnbind(intent);
    }

    private final IBinder mBinder = new LocalBinder();

    /**
     * Initializes a reference to the local Bluetooth adapter.
     *
     * @return Return true if the initialization is successful.
     */
    public boolean initialize() {
        // For API level 18 and above, get a reference to BluetoothAdapter through
        // BluetoothManager.
        if (mBluetoothManager == null) {
            mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
            if (mBluetoothManager == null) {
                Log.e(TAG, "Unable to initialize BluetoothManager.");
                return false;
            }
        }

        mBluetoothAdapter = mBluetoothManager.getAdapter();
        if (mBluetoothAdapter == null) {
            Log.e(TAG, "Unable to obtain a BluetoothAdapter.");
            return false;
        }

        return true;
    }

    /**
     * Connects to the GATT server hosted on the Bluetooth LE device.
     *
     * @param address The device address of the destination device.
     *
     * @return Return true if the connection is initiated successfully. The connection result
     *         is reported asynchronously through the
     *         {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
     *         callback.
     */
    public boolean connect(final String address) {
        if (mBluetoothAdapter == null || address == null) {
            Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
            return false;
        }
/*
        // Previously connected device.  Try to reconnect.
        if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress)
                && mBluetoothGatt != null) {
            Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection.");
            if (mBluetoothGatt.connect()) {
                mConnectionState = STATE_CONNECTING;
                return true;
            } else {
                return false;
            }
        }
*/
        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
        if (device == null) {
            Log.w(TAG, "Device not found.  Unable to connect.");
            return false;
        }
        // We want to directly connect to the device, so we are setting the autoConnect
        // parameter to false.
        if(mBluetoothGatt != null)
        {
            mBluetoothGatt.close();
            mBluetoothGatt = null;
        }
        mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
        //mBluetoothGatt.connect();
        
        Log.d(TAG, "Trying to create a new connection.");
        return true;
    }

    /**
     * Disconnects an existing connection or cancel a pending connection. The disconnection result
     * is reported asynchronously through the
     * {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
     * callback.
     */
    public void disconnect() {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.disconnect();
    }

    /**
     * After using a given BLE device, the app must call this method to ensure resources are
     * released properly.
     */
    public void close() {
        if (mBluetoothGatt == null) {
            return;
        }
        mBluetoothGatt.close();
        mBluetoothGatt = null;
    }

    /**
     * Request a read on a given {@code BluetoothGattCharacteristic}. The read result is reported
     * asynchronously through the {@code BluetoothGattCallback#onCharacteristicRead(android.bluetooth.BluetoothGatt, android.bluetooth.BluetoothGattCharacteristic, int)}
     * callback.
     *
     * @param characteristic The characteristic to read from.
     */
    public void readCharacteristic(BluetoothGattCharacteristic characteristic) {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.readCharacteristic(characteristic);
    }

    /**
     * Enables or disables notification on a give characteristic.
     *
     * @param characteristic Characteristic to act on.
     * @param enabled If true, enable notification.  False otherwise.
     */
    public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic,
                                              boolean enabled) {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.setCharacteristicNotification(characteristic, enabled);
/*
        // This is specific to Heart Rate Measurement.
        if (UUID_HEART_RATE_MEASUREMENT.equals(characteristic.getUuid())) {
            BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
                    UUID.fromString(SampleGattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
            descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
            mBluetoothGatt.writeDescriptor(descriptor);
        }
        */
    }

    /**
     * Retrieves a list of supported GATT services on the connected device. This should be
     * invoked only after {@code BluetoothGatt#discoverServices()} completes successfully.
     *
     * @return A {@code List} of supported services.
     */
    public List<BluetoothGattService> getSupportedGattServices() {
        if (mBluetoothGatt == null) return null;

        return mBluetoothGatt.getServices();
    }
}

5.

// 检查设备是否支持BLE
 if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
            Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
            finish();
        }

        // Initializes a Bluetooth adapter.  For API level 18 and above, get a reference to
        // BluetoothAdapter through BluetoothManager.
// 获取 BluetoothAdapter
        final BluetoothManager bluetoothManager =
                (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
        mBluetoothAdapter = bluetoothManager.getAdapter();

        // Checks if Bluetooth is supported on the device.
        if (mBluetoothAdapter == null) {
            Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
            finish();
            return;
        }

开启蓝牙:

if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) {
   Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
   startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

发现BLE设备：

为了发现BLE设备，使用startLeScan())方法。这个方法需要一个参数BluetoothAdapter.LeScanCallback。你必须实现它的回调函数，那就是返回的扫描结果。因为扫描非常消耗电量，你应当遵守以下准则：

只要找到所需的设备，停止扫描。

不要在循环里扫描，并且对扫描设置时间限制。以前可用的设备可能已经移出范围，继续扫描消耗电池电量。

<1> boolean

startLeScan(BluetoothAdapter.LeScanCallback callback) Starts a scan for Bluetooth LE devices.

<2>boolean

startLeScan(UUID[] serviceUuids, BluetoothAdapter.LeScanCallback callback) Starts a scan for Bluetooth LE devices, looking for devices that advertise given services.

<3>interface

BluetoothAdapter.LeScanCallback

Callback interface used to deliver LE scan results.

1.

    private static final long SCAN_PERIOD = 10000;
    ...
    private void scanLeDevice(final boolean enable) {
        if (enable) {
            // 经过预定扫描期后停止扫描
            mHandler.postDelayed(new Runnable() {
                @Override
                public void run() {
                    mScanning = false;
                    mBluetoothAdapter.stopLeScan(mLeScanCallback);
                }
            }, SCAN_PERIOD);
            mScanning = true;
            mBluetoothAdapter.startLeScan(mLeScanCallback);
        } else {
            mScanning = false;
            mBluetoothAdapter.stopLeScan(mLeScanCallback);
        }
        ...
    }
...
}

2.调用startLeScan(UUID[], BluetoothAdapter.LeScanCallback)),需要提供你的app支持的GATT services的UUID对象数组。

作为BLE扫描结果的接口，下面是BluetoothAdapter.LeScanCallback的实现。

private BluetoothAdapter.LeScanCallback mLeScanCallback =
        new BluetoothAdapter.LeScanCallback() {
    @Override
    public void onLeScan(final BluetoothDevice device, int rssi,
            byte[] scanRecord) {
        runOnUiThread(new Runnable() {
           @Override
           public void run() {
               mLeDeviceListAdapter.addDevice(device);
               mLeDeviceListAdapter.notifyDataSetChanged();
           }
       });
   }
};

3.

public boolean connect(final String address) {
        if (mBluetoothAdapter == null || address == null) {
            Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
            return false;
        }
/*
        // Previously connected device.  Try to reconnect.
        if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress)
                && mBluetoothGatt != null) {
            Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection.");
            if (mBluetoothGatt.connect()) {
                mConnectionState = STATE_CONNECTING;
                return true;
            } else {
                return false;
            }
        }
*/
        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
        if (device == null) {
            Log.w(TAG, "Device not found.  Unable to connect.");
            return false;
        }
        // We want to directly connect to the device, so we are setting the autoConnect
        // parameter to false.
        if(mBluetoothGatt != null)
        {
            mBluetoothGatt.close();
            mBluetoothGatt = null;
        }
        mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
        //mBluetoothGatt.connect();
        
        Log.d(TAG, "Trying to create a new connection.");
        return true;
    }

<暂存>