我是android新手。我正在设计一个Android应用程序,通过蓝牙从硬件设备接收串行数据。我正在研究Htc desire S.我使用示例蓝牙聊天代码来接收数据。但收到的数据不正确。它错过了一些价值观。任何人都可以提供任何其他示例代码,通过蓝牙接收大量数据并将其保存在文件中。
答案 0 :(得分:76)
试试这段代码:
的活动:
package Android.Arduino.Bluetooth;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.TextView;
import android.widget.EditText;
import android.widget.Button;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends Activity
{
TextView myLabel;
EditText myTextbox;
BluetoothAdapter mBluetoothAdapter;
BluetoothSocket mmSocket;
BluetoothDevice mmDevice;
OutputStream mmOutputStream;
InputStream mmInputStream;
Thread workerThread;
byte[] readBuffer;
int readBufferPosition;
int counter;
volatile boolean stopWorker;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button openButton = (Button)findViewById(R.id.open);
Button sendButton = (Button)findViewById(R.id.send);
Button closeButton = (Button)findViewById(R.id.close);
myLabel = (TextView)findViewById(R.id.label);
myTextbox = (EditText)findViewById(R.id.entry);
//Open Button
openButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
findBT();
openBT();
}
catch (IOException ex) { }
}
});
//Send Button
sendButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
sendData();
}
catch (IOException ex) { }
}
});
//Close button
closeButton.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
try
{
closeBT();
}
catch (IOException ex) { }
}
});
}
void findBT()
{
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(mBluetoothAdapter == null)
{
myLabel.setText("No bluetooth adapter available");
}
if(!mBluetoothAdapter.isEnabled())
{
Intent enableBluetooth = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBluetooth, 0);
}
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
if(pairedDevices.size() > 0)
{
for(BluetoothDevice device : pairedDevices)
{
if(device.getName().equals("MattsBlueTooth"))
{
mmDevice = device;
break;
}
}
}
myLabel.setText("Bluetooth Device Found");
}
void openBT() throws IOException
{
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); //Standard SerialPortService ID
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
}
void beginListenForData()
{
final Handler handler = new Handler();
final byte delimiter = 10; //This is the ASCII code for a newline character
stopWorker = false;
readBufferPosition = 0;
readBuffer = new byte[1024];
workerThread = new Thread(new Runnable()
{
public void run()
{
while(!Thread.currentThread().isInterrupted() && !stopWorker)
{
try
{
int bytesAvailable = mmInputStream.available();
if(bytesAvailable > 0)
{
byte[] packetBytes = new byte[bytesAvailable];
mmInputStream.read(packetBytes);
for(int i=0;i<bytesAvailable;i++)
{
byte b = packetBytes[i];
if(b == delimiter)
{
byte[] encodedBytes = new byte[readBufferPosition];
System.arraycopy(readBuffer, 0, encodedBytes, 0, encodedBytes.length);
final String data = new String(encodedBytes, "US-ASCII");
readBufferPosition = 0;
handler.post(new Runnable()
{
public void run()
{
myLabel.setText(data);
}
});
}
else
{
readBuffer[readBufferPosition++] = b;
}
}
}
}
catch (IOException ex)
{
stopWorker = true;
}
}
}
});
workerThread.start();
}
void sendData() throws IOException
{
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream.write(msg.getBytes());
myLabel.setText("Data Sent");
}
void closeBT() throws IOException
{
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
}
}
在这里布局:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
tools:ignore="TextFields,HardcodedText" >
<TextView
android:id="@+id/label"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Type here:" />
<EditText
android:id="@+id/entry"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@id/label"
android:background="@android:drawable/editbox_background" />
<Button
android:id="@+id/open"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_below="@id/entry"
android:layout_marginLeft="10dip"
android:text="Open" />
<Button
android:id="@+id/send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="@id/open"
android:layout_toLeftOf="@id/open"
android:text="Send" />
<Button
android:id="@+id/close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="@id/send"
android:layout_toLeftOf="@id/send"
android:text="Close" />
这里为清单: 添加到应用程序
// permission must be enabled complete
<manifest ....>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<application>
</application>
</manifest>
答案 1 :(得分:5)
我尝试将我的PC(MATLAB)中的连续数据(浮点值转换为字符串)传输到我的手机。但是,仍然我的应用程序误读了分隔符'\ n',但数据仍然出现乱码。因此,我将字符'N'作为分隔符而不是'\ n'(它可能是任何不会作为数据的一部分出现的字符)并且我已经实现了更好的传输速度 - 我只给出了0.1秒的延迟在发送连续样本之间 - 接收器的数据完整性超过99%,即我发送的2000个样本(浮点值),在我的应用程序中只有10个未正确解码。
我的答案很简单:选择“\ r”或“\ n”以外的分隔符,因为与其他字符(如我使用过的字符)相比,这些分隔符会为实时数据传输带来更多问题。如果我们工作得更多,可能我们可以进一步提高传输速率。我希望我的回答可以帮助别人!
答案 2 :(得分:4)
null连接的问题与findBT()函数有关。您必须将设备名称从“MattsBlueTooth”更改为您的设备名称,并确认您的服务/设备的UUID。使用像BLEScanner应用程序这样的东西在Android上进行混淆。
答案 3 :(得分:1)
看看具有onResume()
能力的令人难以置信的Bluetooth Serial课程,这对我帮助很大。
我希望这会有所帮助;)