一. 什么是蓝牙(Bluetooth)?
1.1 BuleTooth是目前使用最广泛的无线通信协议
1.2 主要针对短距离设备通讯(10m)
1.3 常用于连接耳机，鼠标和移动通讯设备等.
二. 与蓝牙相关的API
2.1 BluetoothAdapter:
代表了本地的蓝牙适配器
2.2 BluetoothDevice
代表了一个远程的Bluetooth设备
三. 扫描已经配对的蓝牙设备(1)
注：必须部署在真实手机上，模拟器无法实现
首先需要在AndroidManifest.xml 声明蓝牙权限
<user-permission android:name="android.permission.BLUETOOTH" />
配对蓝牙需要手动操作:
1. 打开设置--> 无线网络 --> 蓝牙 勾选开启
2. 打开蓝牙设置 扫描周围已经开启的蓝牙设备(可以与自己的笔记本电脑进行配对)，点击进行配对
电脑上会弹出提示窗口: 添加设备
显示计算与设备之间的配对码，要求确认是否配对
手机上也会显示类似的提示.
四. 扫描已经配对的蓝牙设备(2)
4.1 获得BluetoothAdapter对象
4.2 判断当前移动设备中是否拥有蓝牙
4.3 判断当前移动设备中蓝牙是否已经打开
4.4 得到所有已经配对的蓝牙设备对象
蓝牙配对实现的核心代码如下:
MainActivity: import java.util.Iterator; import java.util.Set; import android.app.Activity; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class MainActivity extends Activity { private Button button = null; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); button = (Button)findViewById(R.id.buttonId); button.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { //获得BluetoothAdapter对象，该API是android 2.0开始支持的 BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter(); //adapter不等于null，说明本机有蓝牙设备 if(adapter != null){ System.out.println("本机有蓝牙设备！"); //如果蓝牙设备未开启 if(!adapter.isEnabled()){ Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); //请求开启蓝牙设备 startActivity(intent); } //获得已配对的远程蓝牙设备的集合 Set<BluetoothDevice> devices = adapter.getBondedDevices(); if(devices.size()>0){ for(Iterator<BluetoothDevice> it = devices.iterator();it.hasNext();){ BluetoothDevice device = (BluetoothDevice)it.next(); //打印出远程蓝牙设备的物理地址 System.out.println(device.getAddress()); } }else{ System.out.println("还没有已配对的远程蓝牙设备！"); } }else{ System.out.println("本机没有蓝牙设备！"); } } }); } }
修改本机蓝牙设备的可见性,并扫描周围可用的蓝牙设备
1. 修改本机蓝牙设备的可见性
2. 扫描周围可用的蓝牙设备
Eg:
一. 清单文件AdroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.se7en" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="8" /> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".MainActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <uses-permission android:name="android.permission.BLUETOOTH"/> <!-若需要管理蓝牙设备，如修改可见性，则需以下的权限-> <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/> </manifest>
二. 布局文件: main.xml:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" /> <Button android:id="@+id/discoverButton" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="设置可见性"/> <Button android:id="@+id/scanButton" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="开始扫描"/> </LinearLayout>
三. MainActivity:
import android.app.Activity; 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 android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class MainActivity extends Activity { private Button discoverButton = null; private Button scanButton = null; private BluetoothAdapter adapter = null; private BluetoothReceiver bluetoothReceiver = null; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); adapter = BluetoothAdapter.getDefaultAdapter(); discoverButton = (Button)findViewById(R.id.discoverButton); scanButton = (Button)findViewById(R.id.scanButton); //修改蓝牙设备的可见性 discoverButton.setOnClickListener(new OnClickListener(){ @Override public void onClick(View view) { Intent discoverIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE); //设置蓝牙可见性，500表示可见时间（单位：秒），当值大于300时默认为300 discoverIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION,500); startActivity(discoverIntent); } }); scanButton.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { //开始扫描周围蓝牙设备，该方法是异步调用并以广播的机制返回，所以需要创建一个BroadcastReceiver来获取信息 adapter.startDiscovery(); } }); //设定广播接收的filter IntentFilter intentFilter = new IntentFilter(BluetoothDevice.ACTION_FOUND); //创建蓝牙广播信息的receiver bluetoothReceiver = new BluetoothReceiver (); //注册广播接收器 registerReceiver(bluetoothReceiver,intentFilter); } private class BluetoothReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { //获得扫描到的远程蓝牙设备 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE); System.out.println(device.getAddress()); } } }