一. 什么是藍牙(Bluetooth)?
1.1 BuleTooth是目前使用最廣泛的無線通信協議
1.2 主要針對短距離設備通訊(10m)
1.3 常用于連接耳機，鼠標和移動通訊設備等.
二. 與藍牙相關的API
2.1 BluetoothAdapter:
代表了本地的藍牙適配器
2.2 BluetoothDevice
代表了一個遠程的Bluetooth設備
三. 掃描已經配對的藍牙設備(1)
注：必須部署在真實手機上，模擬器無法實現
首先需要在AndroidManifest.xml 聲明藍牙權限
<user-permission android:name="android.permission.BLUETOOTH" />
配對藍牙需要手動操作:
1. 打開設置--> 無線網絡 --> 藍牙 勾選開啟
2. 打開藍牙設置 掃描周圍已經開啟的藍牙設備(可以與自己的筆記本電腦進行配對)，點擊進行配對
電腦上會彈出提示窗口: 添加設備
顯示計算與設備之間的配對碼，要求確認是否配對
手機上也會顯示類似的提示.
四. 掃描已經配對的藍牙設備(2)
4.1 獲得BluetoothAdapter對象
4.2 判斷當前移動設備中是否擁有藍牙
4.3 判斷當前移動設備中藍牙是否已經打開
4.4 得到所有已經配對的藍牙設備對象
藍牙配對實現的核心代碼如下:
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) { //獲得BluetoothAdapter對象，該API是android 2.0開始支持的 BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter(); //adapter不等于null，說明本機有藍牙設備 if(adapter != null){ System.out.println("本機有藍牙設備！"); //如果藍牙設備未開啟 if(!adapter.isEnabled()){ Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); //請求開啟藍牙設備 startActivity(intent); } //獲得已配對的遠程藍牙設備的集合 Set<BluetoothDevice> devices = adapter.getBondedDevices(); if(devices.size()>0){ for(Iterator<BluetoothDevice> it = devices.iterator();it.hasNext();){ BluetoothDevice device = (BluetoothDevice)it.next(); //打印出遠程藍牙設備的物理地址 System.out.println(device.getAddress()); } }else{ System.out.println("還沒有已配對的遠程藍牙設備！"); } }else{ System.out.println("本機沒有藍牙設備！"); } } }); } }
修改本機藍牙設備的可見性,并掃描周圍可用的藍牙設備
1. 修改本機藍牙設備的可見性
2. 掃描周圍可用的藍牙設備
Eg:
一. 清單文件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"/> <!-若需要管理藍牙設備，如修改可見性，則需以下的權限-> <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="設置可見性"/> <Button android:id="@+id/scanButton" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="開始掃描"/> </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); //修改藍牙設備的可見性 discoverButton.setOnClickListener(new OnClickListener(){ @Override public void onClick(View view) { Intent discoverIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE); //設置藍牙可見性，500表示可見時間（單位：秒），當值大于300時默認為300 discoverIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION,500); startActivity(discoverIntent); } }); scanButton.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { //開始掃描周圍藍牙設備，該方法是異步調用并以廣播的機制返回，所以需要創建一個BroadcastReceiver來獲取信息 adapter.startDiscovery(); } }); //設定廣播接收的filter IntentFilter intentFilter = new IntentFilter(BluetoothDevice.ACTION_FOUND); //創建藍牙廣播信息的receiver bluetoothReceiver = new BluetoothReceiver (); //注冊廣播接收器 registerReceiver(bluetoothReceiver,intentFilter); } private class BluetoothReceiver extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { //獲得掃描到的遠程藍牙設備 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE); System.out.println(device.getAddress()); } } } 新聞熱點
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