蓝牙无法连接到OBD2
Bluetooth Unable to connect to OBD2
我正在使用我在 github 上找到的一个应用程序来测试和查看蓝牙聊天如何与我的 ELM327 一起工作,但是当我配对并尝试连接它时,连接失败。在那之后,我尝试获取我的旧 phone 并设置与它的连接并且它起作用了。我什至可以毫无问题地发送数据。我认为这可能与低功耗蓝牙有关(我是 Java 的新手,所以它只是一个赌注)但我真的不知道如何解决,因为 logcat 没有给我一个错误,应用程序只是说它无法连接设备。
这就是我用来测试和了解它的应用程序的来源:
https://github.com/DevExchanges/BluetoothChatAppAndroid
// runs while listening for incoming connections
private class AcceptThread extends Thread {
private final BluetoothServerSocket serverSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
tmp = bluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(APP_NAME, MY_UUID);
} catch (IOException ex) {
ex.printStackTrace();
}
serverSocket = tmp;
}
public void run() {
setName("AcceptThread");
BluetoothSocket socket;
while (state != STATE_CONNECTED) {
try {
socket = serverSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
synchronized (ChatController.this) {
switch (state) {
case STATE_LISTEN:
case STATE_CONNECTING:
// start the connected thread.
connected(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_CONNECTED:
// Either not ready or already connected. Terminate
// new socket.
try {
socket.close();
} catch (IOException e) {
}
break;
}
}
}
}
}
public void cancel() {
try {
serverSocket.close();
} catch (IOException e) {
}
}
}
// runs while attempting to make an outgoing connection
private class ConnectThread extends Thread {
private final BluetoothSocket socket;
private final BluetoothDevice device;
public ConnectThread(BluetoothDevice device) {
this.device = device;
BluetoothSocket tmp = null;
try {
tmp = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
e.printStackTrace();
}
socket = tmp;
}
public void run() {
setName("ConnectThread");
// Always cancel discovery because it will slow down a connection
bluetoothAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
socket.connect();
} catch (IOException e) {
try {
socket.close();
} catch (IOException e2) {
}
connectionFailed();
return;
}
// Reset the ConnectThread because we're done
synchronized (ChatController.this) {
connectThread = null;
}
// Start the connected thread
connected(socket, device);
}
public void cancel() {
try {
socket.close();
} catch (IOException e) {
}
}
}
从 Android 6 开始,您必须在 phone 上启用位置才能使 BLE 工作。仅授予应用位置权限是不够的。
您可以阅读更多相关信息 。
我正在使用我在 github 上找到的一个应用程序来测试和查看蓝牙聊天如何与我的 ELM327 一起工作,但是当我配对并尝试连接它时,连接失败。在那之后,我尝试获取我的旧 phone 并设置与它的连接并且它起作用了。我什至可以毫无问题地发送数据。我认为这可能与低功耗蓝牙有关(我是 Java 的新手,所以它只是一个赌注)但我真的不知道如何解决,因为 logcat 没有给我一个错误,应用程序只是说它无法连接设备。
这就是我用来测试和了解它的应用程序的来源: https://github.com/DevExchanges/BluetoothChatAppAndroid
// runs while listening for incoming connections
private class AcceptThread extends Thread {
private final BluetoothServerSocket serverSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
tmp = bluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(APP_NAME, MY_UUID);
} catch (IOException ex) {
ex.printStackTrace();
}
serverSocket = tmp;
}
public void run() {
setName("AcceptThread");
BluetoothSocket socket;
while (state != STATE_CONNECTED) {
try {
socket = serverSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
synchronized (ChatController.this) {
switch (state) {
case STATE_LISTEN:
case STATE_CONNECTING:
// start the connected thread.
connected(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_CONNECTED:
// Either not ready or already connected. Terminate
// new socket.
try {
socket.close();
} catch (IOException e) {
}
break;
}
}
}
}
}
public void cancel() {
try {
serverSocket.close();
} catch (IOException e) {
}
}
}
// runs while attempting to make an outgoing connection
private class ConnectThread extends Thread {
private final BluetoothSocket socket;
private final BluetoothDevice device;
public ConnectThread(BluetoothDevice device) {
this.device = device;
BluetoothSocket tmp = null;
try {
tmp = device.createInsecureRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
e.printStackTrace();
}
socket = tmp;
}
public void run() {
setName("ConnectThread");
// Always cancel discovery because it will slow down a connection
bluetoothAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
socket.connect();
} catch (IOException e) {
try {
socket.close();
} catch (IOException e2) {
}
connectionFailed();
return;
}
// Reset the ConnectThread because we're done
synchronized (ChatController.this) {
connectThread = null;
}
// Start the connected thread
connected(socket, device);
}
public void cancel() {
try {
socket.close();
} catch (IOException e) {
}
}
}
从 Android 6 开始,您必须在 phone 上启用位置才能使 BLE 工作。仅授予应用位置权限是不够的。
您可以阅读更多相关信息