Android教程網
設為首頁|加入收藏
  1. 首頁
  2. Android 技術
  3. Android 手機
  4. Android 系統教程
  5. Android 游戲
 Android教程網 >> Android技術 >> 關於Android編程 >> Android 藍牙

Android 藍牙

編輯：關於Android編程

正文

 

藍牙是一種支持設備短距離傳輸數據的無線技術。android在2.0以後提供了這方面的支持。
從查找藍牙設備到能夠相互通信要經過幾個基本步驟(本機做為服務器)：
1.設置權限
在manifest中配置

 

[html]
<uses-permission android:name="android.permission.BLUETOOTH"/> 
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/> 

<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>2.啟動藍牙
首先要查看本機是否支持藍牙，獲取BluetoothAdapter藍牙適配器對象


[java]
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
if(mBluetoothAdapter == null){ 
        //表明此手機不支持藍牙  
        return; 
} 
if(!mBluetoothAdapter.isEnabled()){ //藍牙未開啟，則開啟藍牙  
            Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); 
            startActivityForResult(enableIntent, REQUEST_ENABLE_BT); 
} 
//......  
public void onActivityResult(int requestCode, int resultCode, Intent data){ 
       if(requestCode == REQUEST_ENABLE_BT){ 
              if(requestCode == RESULT_OK){ 
                   //藍牙已經開啟   
              } 
       } 
} 

BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(mBluetoothAdapter == null){
        //表明此手機不支持藍牙
        return;
}
if(!mBluetoothAdapter.isEnabled()){ //藍牙未開啟，則開啟藍牙
   Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
   startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
}
//......
public void onActivityResult(int requestCode, int resultCode, Intent data){
       if(requestCode == REQUEST_ENABLE_BT){
              if(requestCode == RESULT_OK){
                   //藍牙已經開啟
              }
       }
}3。發現藍牙設備
這裡可以細分為幾個方面
(1)使本機藍牙處於可見(即處於易被搜索到狀態)，便於其他設備發現本機藍牙
[java]
//使本機藍牙在300秒內可被搜索  
private void ensureDiscoverable() { 
        if (mBluetoothAdapter.getScanMode() != 
            BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) { 
            Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE); 
            discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300); 
            startActivity(discoverableIntent); 
        } 
} 

//使本機藍牙在300秒內可被搜索
private void ensureDiscoverable() {
        if (mBluetoothAdapter.getScanMode() !=
            BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
            Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
            discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
            startActivity(discoverableIntent);
        }
}
(2)查找已經配對的藍牙設備，即以前已經配對過的設備
[java]
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices(); 
if (pairedDevices.size() > 0) { 
    findViewById(R.id.title_paired_devices).setVisibility(View.VISIBLE); 
    for (BluetoothDevice device : pairedDevices) { 
        //device.getName() +" "+ device.getAddress());  
    } 
} else { 
    mPairedDevicesArrayAdapter.add("沒有找到已匹對的設備"); 
} 

  Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
  if (pairedDevices.size() > 0) {
   findViewById(R.id.title_paired_devices).setVisibility(View.VISIBLE);
   for (BluetoothDevice device : pairedDevices) {
    //device.getName() +" "+ device.getAddress());
   }
  } else {
   mPairedDevicesArrayAdapter.add("沒有找到已匹對的設備");
  }
(3)通過mBluetoothAdapter.startDiscovery();搜索設備，要獲得此搜索的結果需要注冊
一個BroadcastReceiver來獲取。先注冊再獲取信息，然後處理
[java]
//注冊，當一個設備被發現時調用onReceive  
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND); 
        this.registerReceiver(mReceiver, filter); 
 
//當搜索結束後調用onReceive  
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED); 
        this.registerReceiver(mReceiver, filter); 
//.......  
private BroadcastReceiver mReceiver = new BroadcastReceiver() { 
        @Override 
        public void onReceive(Context context, Intent intent) { 
            String action = intent.getAction(); 
            if(BluetoothDevice.ACTION_FOUND.equals(action)){ 
                 BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE); 
                  // 已經配對的則跳過  
                 if (device.getBondState() != BluetoothDevice.BOND_BONDED) { 
                      mNewDevicesArrayAdapter.add(device.getName() + "\n" + device.getAddress());  //保存設備地址與名字  
                 } 
            }else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {  //搜索結束  
                if (mNewDevicesArrayAdapter.getCount() == 0) { 
                    mNewDevicesArrayAdapter.add("沒有搜索到設備"); 
                } 
            } 
 
        } 
}; 

//注冊，當一個設備被發現時調用onReceive
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
  this.registerReceiver(mReceiver, filter);

//當搜索結束後調用onReceive
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
  this.registerReceiver(mReceiver, filter);
//.......
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
  @Override
  public void onReceive(Context context, Intent intent) {
   String action = intent.getAction();
   if(BluetoothDevice.ACTION_FOUND.equals(action)){
     BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
               // 已經配對的則跳過
              if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
                   mNewDevicesArrayAdapter.add(device.getName() + "\n" + device.getAddress());  //保存設備地址與名字
              }
   }else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {  //搜索結束
                if (mNewDevicesArrayAdapter.getCount() == 0) {
                    mNewDevicesArrayAdapter.add("沒有搜索到設備");
                }
   }

  }
};
4.建立連接
查找到設備 後，則需要建立本機與其他設備之間的連接。
一般用本機搜索其他藍牙設備時，本機可以作為一個服務端，接收其他設備的連接。
啟動一個服務器端的線程，死循環等待客戶端的連接，這與ServerSocket極為相似。
這個線程在准備連接之前啟動
[java]
//UUID可以看做一個端口號  
private static final UUID MY_UUID = 
        UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66"); 
   //像一個服務器一樣時刻監聽是否有連接建立  
    private class AcceptThread extends Thread{ 
        private BluetoothServerSocket serverSocket; 
         
        public AcceptThread(boolean secure){ 
            BluetoothServerSocket temp = null; 
            try { 
                temp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord( 
                            NAME_INSECURE, MY_UUID); 
            } catch (IOException e) { 
                  Log.e("app", "listen() failed", e); 
            } 
            serverSocket = temp; 
        } 
         
        public void run(){ 
            BluetoothSocket socket=null; 
            while(true){ 
                try { 
                    socket = serverSocket.accept(); 
                } catch (IOException e) { 
                     Log.e("app", "accept() failed", e); 
                     break; 
                } 
            } 
            if(socket!=null){ 
                //此時可以新建一個數據交換線程，把此socket傳進去  
            } 
        } 
         
        //取消監聽  
        public void cancel(){    
            try { 
                serverSocket.close(); 
            } catch (IOException e) { 
                Log.e("app", "Socket Type" + socketType + "close() of server failed", e); 
            } 
        } 
 
} 

//UUID可以看做一個端口號
private static final UUID MY_UUID =
        UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
   //像一個服務器一樣時刻監聽是否有連接建立
    private class AcceptThread extends Thread{
     private BluetoothServerSocket serverSocket;
     
     public AcceptThread(boolean secure){
      BluetoothServerSocket temp = null;
      try {
       temp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord(
          NAME_INSECURE, MY_UUID);
      } catch (IOException e) {
      Log.e("app", "listen() failed", e);
   }
      serverSocket = temp;
     }
     
     public void run(){
      BluetoothSocket socket=null;
      while(true){
       try {
     socket = serverSocket.accept();
    } catch (IOException e) {
      Log.e("app", "accept() failed", e);
                  break;
    }
      }
      if(socket!=null){
       //此時可以新建一個數據交換線程，把此socket傳進去
      }
     }
     
     //取消監聽
     public void cancel(){ 
         try {
             serverSocket.close();
         } catch (IOException e) {
             Log.e("app", "Socket Type" + socketType + "close() of server failed", e);
         }
     }

}搜索到設備後可以獲取設備的地址，通過此地址獲取一個BluetoothDeviced對象，可以看做客戶端，通過此對象device.createRfcommSocketToServiceRecord(MY_UUID);同一個UUID可與服務器建立連接獲取另一個socket對象，由此服務端與客戶端各有一個socket對象，此時
他們可以互相交換數據了。
創立客戶端socket可建立線程
[java]
//另一個設備去連接本機,相當於客戶端  
 private class ConnectThread extends Thread{ 
    private BluetoothSocket socket; 
    private BluetoothDevice device; 
    public ConnectThread(BluetoothDevice device,boolean secure){ 
        this.device = device; 
        BluetoothSocket tmp = null; 
        try { 
    tmp = device.createRfcommSocketToServiceRecord(MY_UUID_SECURE); 
} catch (IOException e) { 
     Log.e("app", "create() failed", e); 
} 
    } 
     
    public void run(){ 
        mBluetoothAdapter.cancelDiscovery();    //取消設備查找  
        try { 
    socket.connect(); 
} catch (IOException e) { 
    try { 
        socket.close(); 
    } catch (IOException e1) { 
         Log.e("app", "unable to close() "+ 
                          " socket during connection failure", e1); 
    } 
    connetionFailed();  //連接失敗  
    return; 
} 
      //此時可以新建一個數據交換線程，把此socket傳進去  
    } 
     
      public void cancel() { 
           try { 
               socket.close(); 
           } catch (IOException e) { 
               Log.e("app", "close() of connect  socket failed", e); 
           } 
       } 
 } 

    //另一個設備去連接本機,相當於客戶端
    private class ConnectThread extends Thread{
     private BluetoothSocket socket;
     private BluetoothDevice device;
     public ConnectThread(BluetoothDevice device,boolean secure){
      this.device = device;
      BluetoothSocket tmp = null;
      try {
    tmp = device.createRfcommSocketToServiceRecord(MY_UUID_SECURE);
   } catch (IOException e) {
     Log.e("app", "create() failed", e);
   }
     }
     
     public void run(){
      mBluetoothAdapter.cancelDiscovery(); //取消設備查找
      try {
    socket.connect();
   } catch (IOException e) {
    try {
     socket.close();
    } catch (IOException e1) {
      Log.e("app", "unable to close() "+
                             " socket during connection failure", e1);
    }
    connetionFailed(); //連接失敗
    return;
   }
         //此時可以新建一個數據交換線程，把此socket傳進去
     }
     
       public void cancel() {
              try {
                  socket.close();
              } catch (IOException e) {
                  Log.e("app", "close() of connect  socket failed", e);
              }
          }
    }
5.建立數據通信線程，進行讀取數據
[java]
//建立連接後，進行數據通信的線程  
    private class ConnectedThread extends Thread{ 
        private BluetoothSocket socket; 
        private InputStream inStream; 
        private OutputStream outStream; 
         
        public ConnectedThread(BluetoothSocket socket){ 
             
            this.socket = socket; 
            try { 
                //獲得輸入輸出流  
                inStream = socket.getInputStream(); 
                outStream = socket.getOutputStream(); 
            } catch (IOException e) { 
                Log.e("app", "temp sockets not created", e); 
            } 
        } 
         
        public void run(){ 
            byte[] buff = new byte[1024]; 
            int len=0; 
            //讀數據需不斷監聽，寫不需要  
            while(true){ 
                try { 
                    len = inStream.read(buff); 
                    //把讀取到的數據發送給UI進行顯示  
                    Message msg = handler.obtainMessage(BluetoothChat.MESSAGE_READ, 
                            len, -1, buff); 
                    msg.sendToTarget(); 
                } catch (IOException e) { 
                    Log.e("app", "disconnected", e); 
                    connectionLost();   //失去連接  
                    start();    //重新啟動服務器  
                    break; 
                } 
            } 
        } 
         
         
        public void write(byte[] buffer) { 
            try { 
                outStream.write(buffer); 
 
                // Share the sent message back to the UI Activity  
                handler.obtainMessage(BluetoothChat.MESSAGE_WRITE, -1, -1, buffer) 
                        .sendToTarget(); 
            } catch (IOException e) { 
                Log.e("app", "Exception during write", e); 
            } 
        } 
 
        public void cancel() { 
            try { 
                socket.close(); 
            } catch (IOException e) { 
                Log.e("app", "close() of connect socket failed", e); 
            } 
        } 
    } 

  1. 上一頁:
  2. 下一頁:
關於Android編程
Android編程入門Android技術基礎Android資訊關於Android編程Android開發Android開發環境Android開發實例
相關文章
熱門文章
android 撥號盤輸入號碼時來電，通話結束後回到撥號盤，如何保存之前輸入的號碼 android虛擬鍵盤彈出遮擋登陸按鈕問題的解決方法 Android學習之——（4）項目中的調用WebService學習 如何快速創建Android模擬器 android圖像繪制(六)獲取本地圖片或拍照圖片等圖片資源 Android拍照得到全尺寸圖片並進行壓縮
[Android]startActivityForResult啟動singleTask的Activity，則onActivitResult()立即回調且resultCode為RESULT_CANCEL

問題現象： 在剛安裝完demo應用未登錄任何帳號
Android-支付寶快捷支付

支付寶的快捷支付Android版業務流程比較麻煩,出現的意外情況比較多.
Android 計時器 Chronometer or handler+timer+timerTask

可能我們在開發中會時常用到計時器這玩意兒，比如在錄像的時候，我們可能需要
ART世界探險(17) - 中層中間代碼MIR

Dalvik字節碼的指令格式指令格式分類Dalvik指令，根據需要的寄存
閱讀排行版
Copyright © Android教程網 All Rights Reserved