问题
I receiving 3 data from Arduino and the data just keep coming in. My problem is the data doesn't update to the new received values.
Here is the screenshot from the logcat: So D/BPM is the value in the textview 68 D/SPo2 is the value in the textview 99 D/temp is the value in textview 28.0
D/read: 71 is for BPM 99 is for SPo2 and 28.11 is for temp. But the textview values just stuck at 68 99 and 28.0. :(
Here are my code for the Android part:
public class Bluetooth_dataDisplay extends Activity {
//declaration
BluetoothAdapter mAdapter;
private ArrayAdapter adapter;
TextView myLabel;
TextView myLabel1;
TextView myLabel2;
Thread workerThread;
byte[] readBuffer;
int readBufferPosition;
volatile boolean stopWorker;
private ListView listview;
private BluetoothSocket bluetoothSocket;
private ConnectedThread mConnectedThread;
final int handlerState = 0;
private StringBuilder recDataString = new StringBuilder();
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case Constants.MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
String readMessage = new String(readBuf, 0, msg.arg1);
recDataString.append(readMessage);
Log.d("read",readMessage);
if (recDataString.charAt(0) == '#')
{
String BPM = recDataString.substring(1,3);
String SPO2= recDataString.substring(3,5);
String Temp= recDataString.substring(5,9);
Log.d("BPM", BPM);
Log.d("SPO2", SPO2);
Log.d("Temp", Temp);
myLabel.setText("BPM" + " " + BPM);
myLabel1.setText("SPO2" +" "+ SPO2);
myLabel2.setText("Temp"+" " + Temp);
}
//recDataString.delete(0, recDataString.length());
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.bluetooth_datadisplay);
myLabel = (TextView)findViewById(R.id.label);
myLabel1 = (TextView)findViewById(R.id.label1);
myLabel2= (TextView)findViewById(R.id.label2);
}//end oncreate
@Override
public void onResume() {
super.onResume(); // Always call the superclass method first
//Get MAC address from BluetoothActivity using intent and Extra
String MAC = getIntent().getStringExtra("MAC");
//must declare every time on a new activity if not will result in null error
mAdapter = BluetoothAdapter.getDefaultAdapter();
//create device and set the MAC address
BluetoothDevice bluetoothDevice = mAdapter.getRemoteDevice(MAC);
// Initiate a connection request in a separate thread
ConnectingThread t = new ConnectingThread(bluetoothDevice);
t.start();
}
@Override
public void onPause()
{
super.onPause();
try {
bluetoothSocket.close();
} catch (IOException e) {
Log.e("error", "terminate thread");
e.printStackTrace();
}
}
/**
* Start the ConnectedThread to begin managing a Bluetooth connection
*
* @param socket The BluetoothSocket on which the connection was made
* @param device The BluetoothDevice that has been connected
*/
public synchronized void connected(BluetoothSocket socket, BluetoothDevice device) {
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
}
private class ConnectingThread extends Thread {
private final BluetoothSocket bluetoothSocket;
private final BluetoothDevice bluetoothDevice;
public ConnectingThread(BluetoothDevice device) {
BluetoothSocket temp = null;
bluetoothDevice = device;
// Get a BluetoothSocket to connect with the given BluetoothDevice
try {
temp = bluetoothDevice.createRfcommSocketToServiceRecord(uuid);
} catch (IOException e) {
e.printStackTrace();
}
bluetoothSocket = temp;
}
public void run() {
// Cancel any discovery as it will slow down the connection
mAdapter.cancelDiscovery();
try {
// This will block until it succeeds in connecting to the device
// through the bluetoothSocket or throws an exception
bluetoothSocket.connect();
} catch (IOException connectException) {
connectException.printStackTrace();
try {
bluetoothSocket.close();
} catch (IOException closeException) {
closeException.printStackTrace();
}
}
// Code to manage the connection in a separate thread
connected(bluetoothSocket, bluetoothDevice);
}
// Cancel an open connection and terminate the thread
public void cancel() {
try {
bluetoothSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* This thread runs during a connection with a remote device.
* It handles all incoming and outgoing transmissions.
*/
private class ConnectedThread extends Thread {
private final BluetoothSocket bluetoothSocket;
private final InputStream mmInputStream;
//private final OutputStream mmOutputStream;
public ConnectedThread(BluetoothSocket socket) {
bluetoothSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
//tmpOut = socket.getOutputStream();
} catch (IOException e) {
}
mmInputStream = tmpIn;
//mmOutputStream = tmpOut;
}//endofConnectedThread(BluetoothSocket socket)
public void run() {
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
bytes = mmInputStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(Constants.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
break;
}
}
}//end of void run
}//end of connectecthread
}
Because Arduino will be sending in data eg #719928.11 so the index will be in this order (0123456789)
Which is why I did it this way to extract the data:
if (recDataString.charAt(0) == '#')
{
String BPM = recDataString.substring(1,3);
String SPO2= recDataString.substring(3,5);
String Temp= recDataString.substring(5,9);
Log.d("BPM", BPM);
Log.d("SPO2", SPO2);
Log.d("Temp", Temp);
myLabel.setText("BPM" + " " + BPM);
myLabel1.setText("SPO2" +" "+ SPO2);
myLabel2.setText("Temp"+" " + Temp);
}
Just to add more details regarding the data: BPM and SPO2 are in int (pulse oximeter) Temp is in float format So if my pulse oximeter is not on. My data look like this #0028.28 where the first 0 is BPM and the second 0 is SPO2. 28.28 is temp
So if the pulse oximeter is on. My data look like this #669928.28 where 66 is BPM and 99 is SPO2. 28.28 is temp. Below is data displayed in Arduino serial monitor:
回答1:
Try this
1 . replace
private StringBuilder recDataString = new StringBuilder();
with this one
private String recDataString = "";
2 . replace
recDataString.append(readMessage);
with this one
recDataString = readMessage ;
Data Parsing for different-2 situations :
if(recDataString.lenth > 0){
//If Oxiometer is OFF
if(recDataString.startsWith(#00) && recDataString.length == 8){
//Do Parsing here #0028.14
String BPM = "0";
String SPO2= "0";
String temp = recDataString.split("00")[1];
myLabel.setText("BPM" + " " + BPM);
myLabel1.setText("SPO2" +" "+ SPO2);
myLabel2.setText("Temp"+" " + Temp);
}
//If Oxiometer is on
if(recDataString.startsWith(#) && recDataString.length() == 10){
//Do Parsing here #779928.08
String BPM = recDataString.substring(1,3);
String SPO2= recDataString.substring(3,5);
String temp = recDataString.substring(5,recDataString.lenth());
myLabel.setText("BPM" + " " + BPM);
myLabel1.setText("SPO2" +" "+ SPO2);
myLabel2.setText("Temp"+" " + Temp);
}
//If String contains # only .
if(recDataString.startsWith(#) && recDataString.length == 1){
//Do nothing or you can decide
}
}
回答2:
Before recDataString.append(readMessage); try to reset the recDataString first, like this:
recDataString.setLength(0);
Because if it does not reset, it will continue append new strings:
#689928.0
#689928.06899719928.11 ...
来源：https://stackoverflow.com/questions/34490859/textview-values-does-not-update-when-data-received-from-arduino