Android Ble低功耗蓝牙开发

一、新建项目

在Android Studio中新建一个项目，如下图所示：

选择No Activity，然后点击Next
点击Finish，完成项目创建。

1、配置build.gradle

在android{}闭包中添加viewBinding，用于获取控件

    buildFeatures {viewBinding true}

添加完成后，点击同步Sync

2、配置清单文件AndroidManifest.xml

在清单文件中，添加蓝牙相关权限如下：

    <!--蓝牙连接权限--><uses-permission android:name="android.permission.BLUETOOTH" /><!--发现和配对蓝牙设备权限--><uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /><!--Android 6~11 定位权限--><uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /><uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /><!--以下三个是Android12中新增，作用与Android12及以上--><!--Android12 的蓝牙权限 如果您的应用与已配对的蓝牙设备通信或者获取当前手机蓝牙是否打开--><uses-permission android:name="android.permission.BLUETOOTH_CONNECT" /><!--Android12 的蓝牙权限 如果您的应用使当前设备可被其他蓝牙设备检测到--><uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" /><!--Android12 的蓝牙权限 如果您的应用查找蓝牙设备（如蓝牙低功耗 (BLE) 外围设备）Android12在不申请定位权限时，必须加上android:usesPermissionFlags="neverForLocation"，否则搜不到设备--><uses-permissionandroid:name="android.permission.BLUETOOTH_SCAN"android:usesPermissionFlags="neverForLocation"tools:targetApi="s" />

二、搜索蓝牙设备

搜索蓝牙设备之前，需要检测手机蓝牙是否已经打开，如果未开启蓝牙，需要先开启蓝牙，才能搜索蓝牙设备。

1、创建MainActivity

在项目包名的位置，右键选择创建Empty Views Activity

勾选Launcher Activity，然后点击Finish

构建activity_main.xml布局：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:id="@+id/main"android:layout_width="match_parent"android:layout_height="match_parent"android:paddingHorizontal="15dp"android:paddingVertical="20dp"tools:context=".MainActivity"><Buttonandroid:id="@+id/btnStartScan"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="搜索蓝牙设备"app:layout_constraintStart_toStartOf="parent"app:layout_constraintTop_toTopOf="parent" /></androidx.constraintlayout.widget.ConstraintLayout>

MainActivity中通过ViewBinding绑定布局，代码如下：

public class MainActivity extends AppCompatActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);ActivityMainBinding mBinding = ActivityMainBinding.inflate(getLayoutInflater());setContentView(mBinding.getRoot());}
}

2、开启蓝牙

MainActivity中添加点击事件：

public class MainActivity extends AppCompatActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);ActivityMainBinding mBinding = ActivityMainBinding.inflate(getLayoutInflater());setContentView(mBinding.getRoot());mBinding.btnStartScan.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {}});}
}

新建个BleUtils工具类，并添加检测蓝牙是否开启、检测是否有权限的方法：

public class BleUtils {/*** 检测是否已经开启蓝牙*/public static boolean isOpenBle(Context context) {BluetoothManager manager = (BluetoothManager) context.getSystemService(Context.BLUETOOTH_SERVICE);if (manager != null) {BluetoothAdapter adapter = manager.getAdapter();if (adapter != null) {return adapter.isEnabled();}}return false;}/*** 检测是否有权限*/public static boolean hasPermission(Context context, String permission) {return context.checkSelfPermission(permission) == PackageManager.PERMISSION_GRANTED;}}

然后在搜索蓝牙设备的点击事件中检测手机是否已开启蓝牙，已开启蓝牙，可以搜索蓝牙设备，未开启蓝牙，需要先开启蓝牙

        mBinding.btnStartScan.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断是否开启蓝牙if (!BleUtils.isOpenBle(mContext)) {openBle();} else {//已开启蓝牙//搜索蓝牙设备searchBle();}}});

开启蓝牙需要打开蓝牙相关的权限

在build.gradle中引入三方库’com.blankj:utilcodex:1.31.1’，用于权限管理和获取各种工具类

    //https://github.com/Blankj/AndroidUtilCode  工具类implementation 'com.blankj:utilcodex:1.31.1'

在MainActivity中添加开启蓝牙方法：

    /*** 开启蓝牙*/@SuppressLint("MissingPermission")public void openBle() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {//Android12以上添加权限if (BleUtils.hasPermission(mContext, android.Manifest.permission.BLUETOOTH_CONNECT)) {//开启蓝牙Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(intent);} else {PermissionUtils.permission(Manifest.permission.BLUETOOTH_CONNECT).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);mContext.startActivity(intent);}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法打开蓝牙");}}).request();}} else {Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);mContext.startActivity(intent);}}

扫描蓝牙设备前，需要检测扫描蓝牙权限是否开启：

    /*** 搜索蓝牙设备,检测搜索权限*/private void searchBle() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {//Android12以上，需要BLUETOOTH_SCAN权限if (!BleUtils.hasPermission(mContext, Manifest.permission.BLUETOOTH_CONNECT)) {PermissionUtils.permission(Manifest.permission.BLUETOOTH_CONNECT).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//开启蓝牙Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(intent);}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法打开蓝牙");}}).request();return;}if (BleUtils.hasPermission(mContext, Manifest.permission.BLUETOOTH_SCAN)) {ToastUtils.showShort("扫描蓝牙");startScan();} else {PermissionUtils.permission(Manifest.permission.BLUETOOTH_SCAN).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//扫描蓝牙ToastUtils.showShort("扫描蓝牙");}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法扫描蓝牙");}}).request();}} else {if (BleUtils.hasPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION)) {ToastUtils.showShort("扫描蓝牙");startScan();} else {PermissionUtils.permission(Manifest.permission.ACCESS_FINE_LOCATION).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//扫描蓝牙ToastUtils.showShort("扫描蓝牙");}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法扫描蓝牙");}}).request();}}}

3、扫描搜索蓝牙设备：

    /*** 开始扫描蓝牙设备*/@SuppressLint("MissingPermission")private void startScan() {BluetoothManager manager = (BluetoothManager) mContext.getSystemService(BLUETOOTH_SERVICE);mBluetoothAdapter = manager.getAdapter();if (mBluetoothAdapter != null) {mScanner = mBluetoothAdapter.getBluetoothLeScanner();LogUtils.i("startScan");if (mScanner != null) {mHandler.removeCallbacks(scanRunnable);mScanner.startScan(scanCallback);mHandler.postDelayed(scanRunnable, 10 * 1000L);}}}/*** 扫描结果*/@SuppressLint("MissingPermission")private final ScanCallback scanCallback = new ScanCallback() {@Overridepublic void onScanResult(int callbackType, ScanResult result) {super.onScanResult(callbackType, result);if (result != null) {BluetoothDevice device = result.getDevice();int rssi = result.getRssi();String address = device.getAddress();ScanDeviceBean scanDeviceBean = new ScanDeviceBean();scanDeviceBean.setDeviceMac(device.getAddress());String deviceName = device.getName();scanDeviceBean.setDeviceName(!TextUtils.isEmpty(deviceName) ? deviceName : "Unknow");scanDeviceBean.setDeviceRssi(rssi);}}@Overridepublic void onScanFailed(int errorCode) {super.onScanFailed(errorCode);}};class StopScanRunnable implements Runnable {StopScanRunnable() {}@Overridepublic void run() {stopScan();}}/*** 停止扫描*/@SuppressLint("MissingPermission")public void stopScan() {LogUtils.i("stopScan");try {if (mScanner != null) {mHandler.removeCallbacks(scanRunnable);mScanner.stopScan(scanCallback);}} catch (Exception e) {throw new RuntimeException(e);}}

其中，ScanDeviceBean为扫描结果实体类：

public class ScanDeviceBean {private String deviceMac;private String deviceName;private int deviceRssi;public String getDeviceMac() {return deviceMac;}public void setDeviceMac(String deviceMac) {this.deviceMac = deviceMac;}public String getDeviceName() {return deviceName;}public void setDeviceName(String deviceName) {this.deviceName = deviceName;}public int getDeviceRssi() {return deviceRssi;}public void setDeviceRssi(int deviceRssi) {this.deviceRssi = deviceRssi;}
}

activity_main.xml中添加RecyclerView，用于展示搜素到的蓝牙设备：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:id="@+id/main"android:layout_width="match_parent"android:layout_height="match_parent"android:paddingHorizontal="15dp"android:paddingVertical="20dp"tools:context=".MainActivity"><Buttonandroid:id="@+id/btnStartScan"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="搜索蓝牙设备"app:layout_constraintStart_toStartOf="parent"app:layout_constraintTop_toTopOf="parent" /><androidx.recyclerview.widget.RecyclerViewandroid:id="@+id/recyclerView"android:layout_width="match_parent"android:layout_height="wrap_content"app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"app:layout_constraintTop_toBottomOf="@+id/btnStartScan" /></androidx.constraintlayout.widget.ConstraintLayout>

将搜索到的蓝牙设备显示到列表中：

    //https://github.com/CymChad/BaseRecyclerViewAdapterHelperimplementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:3.0.4'

DeviceAdapter ：

public class DeviceAdapter extends BaseQuickAdapter<ScanDeviceBean, BaseViewHolder> {public DeviceAdapter() {super(R.layout.item_device);}@Overrideprotected void convert(@NonNull BaseViewHolder baseViewHolder, ScanDeviceBean deviceEntity) {baseViewHolder.setText(R.id.tv_name, deviceEntity.getDeviceName());baseViewHolder.setText(R.id.tv_address, deviceEntity.getDeviceMac());baseViewHolder.setText(R.id.tv_rssi, deviceEntity.getDeviceRssi()+"dBm");}
}

item_device布局：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="wrap_content"android:paddingVertical="8dp"><ImageViewandroid:id="@+id/imageView"android:layout_width="50dp"android:layout_height="50dp"android:padding="8dp"app:layout_constraintStart_toStartOf="parent"app:layout_constraintTop_toTopOf="parent"app:srcCompat="@drawable/icon_bluetooth" /><TextViewandroid:id="@+id/tv_name"android:layout_width="0dp"android:layout_height="wrap_content"android:layout_marginStart="10dp"android:layout_marginTop="4dp"android:layout_marginEnd="10dp"android:textColor="@color/black"android:textSize="14sp"android:textStyle="bold"app:layout_constraintEnd_toStartOf="@+id/tv_rssi"app:layout_constraintStart_toEndOf="@+id/imageView"app:layout_constraintTop_toTopOf="@+id/imageView"tools:text="BLE Name" /><TextViewandroid:id="@+id/tv_address"android:layout_width="0dp"android:layout_height="wrap_content"android:layout_marginStart="10dp"android:layout_marginEnd="10dp"android:layout_marginBottom="4dp"android:textSize="12sp"app:layout_constraintBottom_toBottomOf="@+id/imageView"app:layout_constraintEnd_toStartOf="@+id/tv_rssi"app:layout_constraintStart_toEndOf="@+id/imageView"tools:text="32:65:CF:0A:DA:87" /><TextViewandroid:id="@+id/tv_rssi"android:layout_width="wrap_content"android:layout_height="wrap_content"app:layout_constraintBottom_toBottomOf="parent"app:layout_constraintEnd_toEndOf="parent"app:layout_constraintTop_toTopOf="parent"tools:text="-62dBm" /></androidx.constraintlayout.widget.ConstraintLayout>

蓝牙图标icon_bluetooth.xml：

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<vector xmlns:android="http://schemas.android.com/apk/res/android"android:width="48dp"android:height="48dp"android:autoMirrored="true"android:tint="#000000"android:viewportWidth="24.0"android:viewportHeight="24.0"><pathandroid:fillColor="@android:color/white"android:pathData="M14.24,12.01l2.32,2.32c0.28,-0.72 0.44,-1.51 0.44,-2.33 0,-0.82 -0.16,-1.59 -0.43,-2.31l-2.33,2.32zM19.53,6.71l-1.26,1.26c0.63,1.21 0.98,2.57 0.98,4.02s-0.36,2.82 -0.98,4.02l1.2,1.2c0.97,-1.54 1.54,-3.36 1.54,-5.31 -0.01,-1.89 -0.55,-3.67 -1.48,-5.19zM15.71,7.71L10,2L9,2v7.59L4.41,5 3,6.41 8.59,12 3,17.59 4.41,19 9,14.41L9,22h1l5.71,-5.71 -4.3,-4.29 4.3,-4.29zM11,5.83l1.88,1.88L11,9.59L11,5.83zM12.88,16.29L11,18.17v-3.76l1.88,1.88z" /></vector>

在MainActivity中展示蓝牙设备列表：

public class MainActivity extends AppCompatActivity {private Context mContext;private BluetoothAdapter mBluetoothAdapter;private BluetoothLeScanner mScanner;private static final Handler mHandler = new Handler();private final Runnable scanRunnable = new StopScanRunnable();private final ArrayList<ScanDeviceBean> mDeviceList = new ArrayList<>();private DeviceAdapter mDeviceAdapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);ActivityMainBinding mBinding = ActivityMainBinding.inflate(getLayoutInflater());setContentView(mBinding.getRoot());mContext = getApplicationContext();mDeviceAdapter = new DeviceAdapter();mBinding.recyclerView.setAdapter(mDeviceAdapter);mBinding.btnStartScan.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {//判断是否开启蓝牙if (!BleUtils.isOpenBle(mContext)) {openBle();} else {//已开启蓝牙//搜索蓝牙设备searchBle();}}});}/*** 开启蓝牙*/@SuppressLint("MissingPermission")public void openBle() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {//Android12以上添加权限if (BleUtils.hasPermission(mContext, android.Manifest.permission.BLUETOOTH_CONNECT)) {//开启蓝牙Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(intent);} else {PermissionUtils.permission(Manifest.permission.BLUETOOTH_CONNECT).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);mContext.startActivity(intent);}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法打开蓝牙");}}).request();}} else {Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);mContext.startActivity(intent);}}/*** 搜索蓝牙设备,检测搜索权限*/@SuppressLint("MissingPermission")private void searchBle() {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {//Android12以上，需要BLUETOOTH_SCAN权限if (!BleUtils.hasPermission(mContext, Manifest.permission.BLUETOOTH_CONNECT)) {PermissionUtils.permission(Manifest.permission.BLUETOOTH_CONNECT).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//开启蓝牙Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);startActivity(intent);}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法打开蓝牙");}}).request();return;}if (BleUtils.hasPermission(mContext, Manifest.permission.BLUETOOTH_SCAN)) {ToastUtils.showShort("扫描蓝牙");startScan();} else {PermissionUtils.permission(Manifest.permission.BLUETOOTH_SCAN).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//扫描蓝牙ToastUtils.showShort("扫描蓝牙");}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法扫描蓝牙");}}).request();}} else {if (BleUtils.hasPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION)) {ToastUtils.showShort("扫描蓝牙");startScan();} else {PermissionUtils.permission(Manifest.permission.ACCESS_FINE_LOCATION).callback(new PermissionUtils.SimpleCallback() {@Overridepublic void onGranted() {//扫描蓝牙ToastUtils.showShort("扫描蓝牙");}@Overridepublic void onDenied() {ToastUtils.showShort("Android12无此权限，无法扫描蓝牙");}}).request();}}}/*** 开始扫描蓝牙设备*/@SuppressLint("MissingPermission")private void startScan() {BluetoothManager manager = (BluetoothManager) mContext.getSystemService(BLUETOOTH_SERVICE);mBluetoothAdapter = manager.getAdapter();if (mBluetoothAdapter != null) {mScanner = mBluetoothAdapter.getBluetoothLeScanner();LogUtils.i("startScan");if (mScanner != null) {mHandler.removeCallbacks(scanRunnable);mScanner.startScan(scanCallback);mHandler.postDelayed(scanRunnable, 10 * 1000L);}}}/*** 扫描结果*/@SuppressLint("MissingPermission")private final ScanCallback scanCallback = new ScanCallback() {@Overridepublic void onScanResult(int callbackType, ScanResult result) {super.onScanResult(callbackType, result);if (result != null) {BluetoothDevice device = result.getDevice();int rssi = result.getRssi();String address = device.getAddress();ScanDeviceBean scanDeviceBean = new ScanDeviceBean();scanDeviceBean.setDeviceMac(device.getAddress());String deviceName = device.getName();scanDeviceBean.setDeviceName(!TextUtils.isEmpty(deviceName) ? deviceName : "Unknow");scanDeviceBean.setDeviceRssi(rssi);boolean isContain = false;for (ScanDeviceBean bean : mDeviceList) {if (bean.getDeviceMac().equals(scanDeviceBean.getDeviceMac())) {isContain = true;break;}}if (!isContain) {mDeviceList.add(scanDeviceBean);mDeviceAdapter.setList(mDeviceList);}}}@Overridepublic void onScanFailed(int errorCode) {super.onScanFailed(errorCode);}};class StopScanRunnable implements Runnable {StopScanRunnable() {}@Overridepublic void run() {stopScan();}}/*** 停止扫描*/@SuppressLint("MissingPermission")public void stopScan() {LogUtils.i("stopScan");try {if (mScanner != null) {mHandler.removeCallbacks(scanRunnable);mScanner.stopScan(scanCallback);}} catch (Exception e) {throw new RuntimeException(e);}}}

搜索到的蓝牙设备列表如下：

三、连接蓝牙设备

蓝牙设备列表添加点击事件，点击连接蓝牙设备：

        mDeviceAdapter.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(@NonNull BaseQuickAdapter<?, ?> adapter, @NonNull View view, int position) {String deviceMac = mDeviceList.get(position).getDeviceMac();connectBle(deviceMac);}});

    /*** 连接蓝牙设备** @param macAddress 蓝牙设备地址*/@SuppressLint("MissingPermission")public void connectBle(String macAddress) {if (mBluetoothAdapter != null && !TextUtils.isEmpty(macAddress)) {BluetoothDevice remoteDevice = mBluetoothAdapter.getRemoteDevice(macAddress);if (remoteDevice != null) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {//BluetoothDevice.TRANSPORT_AUTO:对于GATT连接到远程双模设备无物理传输优先。//BluetoothDevice.TRANSPORT_BREDR:GATT连接到远程双模设备优先BR/EDR。//BluetoothDevice.TRANSPORT_LE:GATT连接到远程双模设备优先BLE。mBluetoothGatt = remoteDevice.connectGatt(mContext, false, mBleGattCallBack, BluetoothDevice.TRANSPORT_LE);} else {mBluetoothGatt = remoteDevice.connectGatt(mContext, false, mBleGattCallBack);}}}}

连接状态回调：

/*** 连接状态回调*/@SuppressLint("MissingPermission")class BleGattCallBack extends BluetoothGattCallback {//        @Override
//        public void onMtuChanged(BluetoothGatt gatt, int mtu, int status) {
//            super.onMtuChanged(gatt, mtu, status);
//            if (status == BluetoothGatt.GATT_SUCCESS) {
//                LogUtils.e( "request mtu success.约定后的MTU值为：" + mtu);
//            } else {
//                LogUtils.e( "request mtu failed.");
//            }
//
//            if (mBluetoothGatt != null) {
//                mBluetoothGatt.discoverServices();
//            }
//        }@Overridepublic void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {super.onConnectionStateChange(gatt, status, newState);LogUtils.i("onConnectionStateChange status " + status + "   newState " + newState);if (newState == BluetoothProfile.STATE_CONNECTED) {LogUtils.i("蓝牙连接成功，开始发现服务");//                        boolean mut = gatt.requestMtu(500);//如有需要可以申请扩容
//                        LogUtils.i("申请MTU扩容" + mut);if (mBluetoothGatt != null) {mBluetoothGatt.discoverServices();}} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {LogUtils.e("蓝牙连接已断开");}}@Overridepublic void onServicesDiscovered(BluetoothGatt gatt, int status) {super.onServicesDiscovered(gatt, status);LogUtils.i("onServicesDiscovered status " + status);if (status == BluetoothGatt.GATT_SUCCESS) {LogUtils.i("成功获取服务，开始获取服务里的特性");if (mBluetoothGatt != null) {List<BluetoothGattService> services = mBluetoothGatt.getServices();for (BluetoothGattService gattService : services) {LogUtils.d("服务uuid " + gattService.getUuid());List<BluetoothGattCharacteristic> characteristics = gattService.getCharacteristics();for (BluetoothGattCharacteristic gattCharacteristic : characteristics) {int charaProp = gattCharacteristic.getProperties();StringBuilder stringBuilder = new StringBuilder();if ((charaProp & BluetoothGattCharacteristic.PROPERTY_READ) > 0) {stringBuilder.append(" 可读 ");}if ((charaProp & BluetoothGattCharacteristic.PROPERTY_WRITE) > 0) {stringBuilder.append(" 可写 ");}if ((charaProp & BluetoothGattCharacteristic.PROPERTY_NOTIFY) < 0) {stringBuilder.append(" 通知 ");}LogUtils.d("特性uuid " + gattCharacteristic.getUuid() + stringBuilder);}}}} else {LogUtils.e("服务获取失败");}}@Overridepublic void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {super.onCharacteristicRead(gatt, characteristic, status);//Android12及以下，适用此方法if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU) {//适用于Android12及以下LogUtils.i("onCharacteristicRead，(Android12及以下)读取特性：" + characteristic.getUuid() + "，status：" + status);}}@Overridepublic void onCharacteristicRead(@NonNull BluetoothGatt gatt, @NonNull BluetoothGattCharacteristic characteristic, @NonNull byte[] value, int status) {super.onCharacteristicRead(gatt, characteristic, value, status);//Android13及以上，适用此方法LogUtils.i("onCharacteristicRead，(Android13及以上)读取特性：" + characteristic.getUuid() + "，status：" + status);}@Overridepublic void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {super.onCharacteristicWrite(gatt, characteristic, status);LogUtils.i("onCharacteristicWrite，写入特性：" + characteristic.getUuid() + "，status：" + status);if (status == BluetoothGatt.GATT_SUCCESS) {//Android 13及以上版本，characteristic.getValue()方法已过时，可能存在获取不到value的可能，如需要可以通过gatt.readCharacteristic(characteristic)（前提是这个特性可读）String value = Arrays.toString(characteristic.getValue());LogUtils.i("onCharacteristicWrite，写入特性：" + characteristic.getUuid() + "，值：" + value + "，十六进制值：" + BleUtils.bytesToHex(characteristic.getValue()));} else {}}//Descriptor（描述符）中定义的属性用于描述一个characteristic值@Overridepublic void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {super.onDescriptorWrite(gatt, descriptor, status);if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {LogUtils.i("onDescriptorWrite，(Android13及以上)写描述符：" + descriptor.getUuid().toString() + "  status:" + status);} else {LogUtils.i("onDescriptorWrite，(Android12及以下)写描述符：" + descriptor.getUuid().toString() + "  value:" + Arrays.equals(descriptor.getValue(), BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE) + "  status:" + status);}//Android 13及以上版本，descriptor.getValue()方法已过时，获取的value为null，需要可以通过gatt.readDescriptor(descriptor)获取value（前提是这个特性可读）if (status == BluetoothGatt.GATT_SUCCESS) {} else {}}@Overridepublic void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {super.onDescriptorRead(gatt, descriptor, status);//Android12及以下，适用此方法if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU) {//适用于Android12及以下LogUtils.i("onDescriptorRead，(Android12及以下)读描述符：" + descriptor.getUuid().toString());if (status == BluetoothGatt.GATT_SUCCESS) {} else {}}}@Overridepublic void onDescriptorRead(@NonNull BluetoothGatt gatt, @NonNull BluetoothGattDescriptor descriptor, int status, @NonNull byte[] value) {super.onDescriptorRead(gatt, descriptor, status, value);//Android13及以上，适用此方法LogUtils.i("onDescriptorRead，(Android13及以上)读描述符：" + descriptor.getUuid().toString());if (status == BluetoothGatt.GATT_SUCCESS) {} else {}}@Overridepublic void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {//通知特性发生改变super.onCharacteristicChanged(gatt, characteristic);if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU) {//适用于Android12及Android12以下final byte[] value = characteristic.getValue();if (value != null && value.length > 0) {String hexValue = BleUtils.bytesToHex(characteristic.getValue());LogUtils.i("onCharacteristicChanged，(Android12及以下)特性发生改变：" + characteristic.getUuid() + "，值：" + hexValue);}}}@Overridepublic void onCharacteristicChanged(@NonNull BluetoothGatt gatt, @NonNull BluetoothGattCharacteristic characteristic, @NonNull byte[] value) {super.onCharacteristicChanged(gatt, characteristic, value);//Android13及以上，适用此方法if (value.length > 0) {String hexValue = BleUtils.bytesToHex(value);LogUtils.i("onCharacteristicChanged，(Android13及以上)特性发生改变：" + characteristic.getUuid() + "，值：" + hexValue);}}}

四、读、写、通知

根据uuid，获取相应的特性，就可以进行读、写、通知操作：

 /*** 读取特性值** @param gattCharacteristic 要读取的特性*/private boolean readCharacteristic(BluetoothGattCharacteristic gattCharacteristic) {if (mBluetoothGatt != null) {boolean readState = mBluetoothGatt.readCharacteristic(gattCharacteristic);LogUtils.i("readCharacteristic " + readState);return readState;}return false;}/*** 写入特性值** @param gattCharacteristic 要写入的特性*/private boolean writeCharacteristic(BluetoothGattCharacteristic gattCharacteristic, byte[] data) {if (mBluetoothGatt != null) {boolean writeState;if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {//Android13及以上，适用此方法writeState = mBluetoothGatt.writeCharacteristic(gattCharacteristic,data, BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT)== BluetoothStatusCodes.SUCCESS;} else {//Android12及以下，适用此方法writeState = mBluetoothGatt.writeCharacteristic(gattCharacteristic);}LogUtils.i("writeCharacteristic " + writeState);return writeState;}return false;}/*** 设置特性通知** @param gattCharacteristic 需要获取通知的特性* @param descriptorUuid     描述UUID* @param enable             true 获取特性变化通知 false 关闭通知*/private boolean setCharacteristicNotification(BluetoothGattCharacteristic gattCharacteristic, String descriptorUuid, boolean enable) {if (mBluetoothGatt != null) {boolean notifyCharacter = mBluetoothGatt.setCharacteristicNotification(gattCharacteristic, enable);if (notifyCharacter) {BluetoothGattDescriptor descriptor = gattCharacteristic.getDescriptor(UUID.fromString(descriptorUuid));if (descriptor != null) {boolean notifyState;if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {//Android13及以上，适用此方法notifyState = mBluetoothGatt.writeDescriptor(descriptor,enable ? BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE : BluetoothGattDescriptor.DISABLE_NOTIFICATION_VALUE)== BluetoothStatusCodes.SUCCESS;} else {//Android12及以下，适用此方法if (enable) {descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);} else {descriptor.setValue(BluetoothGattDescriptor.DISABLE_NOTIFICATION_VALUE);}notifyState = mBluetoothGatt.writeDescriptor(descriptor);}LogUtils.i("setCharacteristicNotification notifyState " + notifyState);return notifyState;}}}return false;}

五、判断手机已连接的蓝牙设备

判断是否有已经连接的蓝牙设备，通过此方法可以看到手机连接了几个蓝牙设备，获取已连接蓝牙设备的信息：

    /*** 判断是否有已经连接的蓝牙设备*/public void isConnectedBleDevice() {BluetoothManager manager = (BluetoothManager) mContext.getSystemService(BLUETOOTH_SERVICE);if (manager != null) {List<BluetoothDevice> connectedDevices = manager.getConnectedDevices(BluetoothProfile.GATT);LogUtils.d("connectedDevices.size() " + connectedDevices.size());for (BluetoothDevice bluetoothDevice : connectedDevices) {LogUtils.d(bluetoothDevice.getAddress() + " " + bluetoothDevice.getName());}}}

六、刷新缓存

蓝牙断开连接后，通过反射的方式刷新缓存：

    /*** 刷新缓存*/public void refreshDeviceCache() {if (mBluetoothGatt != null) {try {Method localMethod = mBluetoothGatt.getClass().getMethod("refresh");Boolean success = (Boolean) localMethod.invoke(mBluetoothGatt);LogUtils.i("refreshDeviceCache, is success: " + success);} catch (Exception e) {LogUtils.e("exception occur while refreshing device: " + e.getMessage());e.printStackTrace();}}}