Question

我尝试编写仅连接到其他蓝牙设备的代码。我使用https://developer.android.com上提供的标准示例代码，但有些代码无法正常工作。它显示异常错误，如下所示： java.io.IOException：读取失败，socket可能关闭或超时，读取ret：-1 任何好友都可以帮助我：我的代码是： btAdaptor.startDiscovery（）; registerReceiver（bReceiver，新的IntentFilter（BluetoothDevice.ACTION_FOUND））;

final BroadcastReceiver bReceiver = new BroadcastReceiver() {
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        // When discovery finds a device
        if (BluetoothDevice.ACTION_FOUND.equals(action)) {
            // Get the BluetoothDevice object from the Intent
            device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            // add the name and the MAC address of the object to the
           // arrayAdapter
            BTArrayAdapter.add(device.getName() + "\n"+ device.getAddress());
            BTArrayAdapter.notifyDataSetChanged();
            Devices.add(device);
            AlertDialog.Builder BT_Paired = new AlertDialog.Builder(MainActivity.this);
            BT_Paired.setTitle("Available Device:");

            BT_Paired.setAdapter(BTArrayAdapter, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialogInterface, final int i) {
                    btAdaptor.cancelDiscovery();
                    BT_name = BTArrayAdapter.getItem(i);
                    AlertDialog.Builder BTpair = new AlertDialog.Builder(MainActivity.this);
                    BTpair.setMessage(BT_name);
                    BTpair.setTitle("Your Selected Item is:");
                    AlertDialog.Builder ok = BTpair.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                               BluetoothDevice selectedDevice = Devices.get(i);

                            ConnectThread connect = new ConnectThread(selectedDevice);
                            connect.start();
                        }
                    });

                    BTpair.show();
                }
            });

            AlertDialog alertDialog = BT_Paired.create();
            alertDialog.show();
       }
    }
};

private class ConnectThread extends Thread {
    private final BluetoothSocket mmSocket;
   private final BluetoothDevice mmDevice;

    public ConnectThread(BluetoothDevice device) {
        // Use a temporary object that is later assigned to mmSocket,
        // because mmSocket is final
        BluetoothSocket tmp = null;
        mmDevice = device;

        // Get a BluetoothSocket to connect with the given BluetoothDevice
        try {
            // MY_UUID is the app's UUID string, also used by the server code
            tmp = device.createRfcommSocketToServiceRecord(MY_UUID);

       } catch (IOException e) { }
       mmSocket = tmp;

    }

    public void run() {
        // Cancel discovery because it will slow down the connection

        btAdaptor.cancelDiscovery();

        try {
            // Connect the device through the socket. This will block
            // until it succeeds or throws an exception
               mmSocket.connect();
                    } catch (IOException connectException) {
           // Unable to connect; close the socket and get out
                           try {
                        mmSocket.close();
            } catch (IOException closeException) { }
          return;
        }

        // Do work to manage the connection (in a separate thread)

        mHandler.obtainMessage(SUCCESS_CONNECT,mmSocket).sendToTarget();

    }

    /** Will cancel an in-progress connection, and close the socket */
    public void cancel() {
        try {
            mmSocket.close();
        } catch (IOException e) { }
    }
}

Android应用到蓝牙设备连接

0 个答案: