我试图在我的Android应用程序中使用蓝牙收到的字符串，但我无法使用if语句，实际上我想比较收到的字符串与我的操作，以便用户发送字符串和Android应用程序做一些任务根据因为我会加入它，所以请告诉我如何做到这一点，谢谢，请帮助我:(
public static final UUID SERVICE_UUID = UUID.fromString("34B1CF4D-1069-4AD6-89B6-E161D79BE4D9");
private static final String TAG = "BluetoothService";
private static BluetoothService instance = new BluetoothService();
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private Handler mHandler; // handler that gets info from Bluetooth service
private BluetoothService() {
mHandler = new Handler(new Handler.Callback() {
@Override
public boolean handleMessage(Message msg) {
Log.d(TAG, "got a notification in " + Thread.currentThread());
return false;
}
});
}
public static BluetoothService getInstance() {
return instance;
}
public void connectToDevice(BluetoothDevice device) {
//close existing connections
if (mConnectedThread != null) mConnectedThread.cancel();
if (mConnectThread != null) mConnectThread.cancel();
mConnectThread = new ConnectThread(device);
mConnectThread.start();
}
private void manageMyConnectedSocket(BluetoothSocket mmSocket) {
if (mmSocket.isConnected()) {
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
}
}
public boolean send(String command) {
return mConnectedThread.write(command);
}
public void registerNewHandlerCallback(Handler.Callback callback) {
mHandler = new Handler(callback );
}
// Defines several constants used when transmitting messages between the
// service and the UI.
public interface MessageConstants {
public static final int MESSAGE_READ = 0;
public static final int MESSAGE_WRITE = 1;
public static final int MESSAGE_TOAST = 2;
}
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;
try {
// Get a BluetoothSocket to connect with the given BluetoothDevice.
// SERVICE_UUID is the app's UUID string, also used in the server code.
tmp = device.createRfcommSocketToServiceRecord(SERVICE_UUID);
} catch (IOException e) {
Log.e(TAG, "creatE() error socket", e);
}
mmSocket = tmp;
}
public void run() {
try {
// Connect to the remote device through the socket. This call blocks
// until it succeeds or throws an exception.
mmSocket.connect();
} catch (IOException connectException) {
// Unable to connect; close the socket and return.
try {
mmSocket.close();
} catch (IOException closeException) {
Log.e(TAG, "Could not close the client socket", closeException);
}
return;
}
// The connection attempt succeeded. Perform work associated with
// the connection in a separate thread.
manageMyConnectedSocket(mmSocket);
}
// Closes the client socket and causes the thread to finish.
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "Could not close the client socket", e);
}
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams; using temp objects because
// member streams are final.
try {
tmpIn = socket.getInputStream();
} catch (IOException e) {
Log.e(TAG, "Error occurred when creating input stream", e);
}
try {
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.e(TAG, "Error occurred when creating output stream", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
// Keep listening to the InputStream until an exception occurs.
while (true) {
try {
// Read from the InputStream.
byte[] buffer = new byte[4];
int read = mmInStream.read(buffer);
if (read < 4) {
this.cancel();
}
int dataLength = ByteBuffer.wrap(buffer).getInt();
buffer = new byte[dataLength];
read = mmInStream.read(buffer);
if (read < dataLength) {
this.cancel();
}
String command = new String(buffer);
// Send the obtained bytes to the UI activity.
Message readMsg = mHandler.obtainMessage(MessageConstants.MESSAGE_READ, -1, -1, command);
readMsg.sendToTarget();
Log.d(TAG, "reading values");
} catch (IOException e) {
Log.d(TAG, "Input stream was disconnected", e);
break;
}
}
}
// Call this from the main activity to send data to the remote device.
public boolean write(String command) {
try {
// Allocate bytes for integer indicating size and message itself
ByteBuffer bb = ByteBuffer.allocate(4 + command.length())
.putInt(command.length())
.put(command.getBytes());
mmOutStream.write(bb.array());
mmOutStream.flush();
// Share the sent message with the UI activity.
Message writtenMsg = mHandler.obtainMessage(MessageConstants.MESSAGE_WRITE, -1, -1, command);
writtenMsg.sendToTarget();
return true;
} catch (IOException e) {
Log.e(TAG, "Error occurred when sending data", e);
// Send a failure message back to the activity.
Message writeErrorMsg =
mHandler.obtainMessage(MessageConstants.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString("toast",
"Couldn't send data to the other device");
writeErrorMsg.setData(bundle);
mHandler.sendMessage(writeErrorMsg);
}
return false;
}
// Call this method from the main activity to shut down the connection.
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "Could not close the connect socket", e);
}
}
}
MainActivity
bs.registerNewHandlerCallback(new Handler.Callback() {
@Override
public boolean handleMessage(Message msg) {
try {
String toasttext = "";
String a = "";
// Log.d(TAG, "got a notification in " + Thread.currentThread());
if (msg.what == BluetoothService.MessageConstants.MESSAGE_READ ){
toasttext = "";
//here i want to use received string in if statement , .....
}
else if (msg.what == BluetoothService.MessageConstants.MESSAGE_TOAST) {
toasttext = "Info: ";
}
else if (msg.what == BluetoothService.MessageConstants.MESSAGE_WRITE) {
toasttext = "Sending to device: ";
}
toasttext += msg.obj.toString();
Toast.makeText(getApplicationContext(), toasttext, Toast.LENGTH_LONG).show();
} catch (Throwable t) {
Log.e(TAG,null, t);
}
return false;
}
});
答案 0 :(得分：0)
如果要与字符串进行比较，则需要使用equals（）。
String str1 = "myString1";
String str2 = "myString2";
String str3 = "myString1";
if(str1.Equals(str2)) {
// Will not execute
doSomething();
} else if(str1.equals(str3)) {
// Will execute because str1 is the same as str3
doOtherThing();
}
将运行doOtherThing（）。您可以使用此模型将蓝牙字符串存储在str1中，然后将其与您想要的任何字符串进行比较。