Java 从android应用程序成功发送数据后,蓝牙打印机未打印数据
请帮忙。我正在开发一个简单的蓝牙打印机应用程序,我想打印用户输入的数据。我的代码工作正常,但打印机无法打印数据。 目前我正在使用MTP-U-85蓝牙打印机。 当我从应用程序发送数据时,打印机颜色从绿色变为蓝色。此外,当我连接和断开蓝牙时,颜色在绿色和蓝色、蓝色和绿色之间变化。一切正常,但数据无法打印 我会给你我的密码Java 从android应用程序成功发送数据后,蓝牙打印机未打印数据,java,android,printing,bluetooth,Java,Android,Printing,Bluetooth,请帮忙。我正在开发一个简单的蓝牙打印机应用程序,我想打印用户输入的数据。我的代码工作正常,但打印机无法打印数据。 目前我正在使用MTP-U-85蓝牙打印机。 当我从应用程序发送数据时,打印机颜色从绿色变为蓝色。此外,当我连接和断开蓝牙时,颜色在绿色和蓝色、蓝色和绿色之间变化。一切正常,但数据无法打印 我会给你我的密码 import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; impor
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Set;
import java.util.UUID;
public class MainActivity extends AppCompatActivity {
// will show the statuses like bluetooth open, close or data sent
TextView myLabel;
// will enable user to enter any text to be printed
EditText myTextbox;
// android built in classes for bluetooth operations
BluetoothAdapter mBluetoothAdapter;
BluetoothSocket mmSocket;
BluetoothDevice mmDevice;
// needed for communication to bluetooth device / network
OutputStream mmOutputStream;
InputStream mmInputStream;
Thread workerThread;
byte[] readBuffer;
int readBufferPosition;
volatile boolean stopWorker;
Button openButton ;
Button sendButton ;
Button closeButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
// we are going to have three buttons for specific functions
openButton = findViewById(R.id.open);
sendButton = findViewById(R.id.send);
closeButton = findViewById(R.id.close);
// text label and input box
myLabel = (TextView) findViewById(R.id.label);
myTextbox = (EditText) findViewById(R.id.entry);
openButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
findBT();
openBT();
} catch (IOException ex) {
ex.printStackTrace();
}
}
});
}
catch(Exception e)
{
e.printStackTrace();
}
// send data typed by the user to be printed
sendButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
sendData();
} catch (IOException ex) {
ex.printStackTrace();
}
}
});
// close bluetooth connection
closeButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
closeBT();
} catch (IOException ex) {
ex.printStackTrace();
}
}
});
}
private void closeBT() throws IOException{
try {
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText("Bluetooth Closed");
} catch (Exception e) {
e.printStackTrace();
}
}
// this will send text data to be printed by the bluetooth printer
void sendData() throws IOException {
try {
// if(mmOutputStream==null) {
// the text typed by the user
EditText myTextbox = (EditText) findViewById(R.id.entry);
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream = mmSocket.getOutputStream();
mmOutputStream.write(msg.getBytes());
// tell the user data were sent
myLabel.setText("Data sent.");
// }
} catch (Exception e) {
e.printStackTrace();
}
}
// tries to open a connection to the bluetooth printer device
void openBT() throws IOException {
try {
// Standard SerialPortService ID
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream = mmSocket.getOutputStream();
mmInputStream = mmSocket.getInputStream();
beginListenForData();
myLabel.setText("Bluetooth Opened");
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* after opening a connection to bluetooth printer device,
* we have to listen and check if a data were sent to be printed.
*/
void beginListenForData()
{
try {
final Handler handler = new Handler();
// this is the ASCII code for a newline character
final byte delimiter = 10;
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
);
// specify US-ASCII encoding
final String data = new String(encodedBytes, "US-ASCII");
readBufferPosition = 0;
// tell the user data were sent to bluetooth printer device
handler.post(new Runnable() {
public void run() {
myLabel.setText(data);
}
});
} else {
readBuffer[readBufferPosition++] = b;
}
}
}
} catch (IOException ex) {
stopWorker = true;
}
}
}
});
workerThread.start();
} catch (Exception e) {
e.printStackTrace();
}
}
private void findBT() {
try {
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) {
// RPP300 is the name of the bluetooth printer device
// we got this name from the list of paired devices
if (device.getAddress().equals("DC:1D:30:35:3E:64")) {
mmDevice = device;
break;
}
}
}
myLabel.setText("Bluetooth device found.");
}catch(Exception e){
e.printStackTrace();
}
}
}
导入android.bluetooth.BluetoothAdapter;
导入android.bluetooth.bluetooth设备;
导入android.bluetooth.BluetoothSocket;
导入android.content.Intent;
导入android.os.Handler;
导入android.support.v7.app.AppActivity;
导入android.os.Bundle;
导入android.view.view;
导入android.widget.Button;
导入android.widget.EditText;
导入android.widget.TextView;
导入java.io.IOException;
导入java.io.InputStream;
导入java.io.OutputStream;
导入java.util.Set;
导入java.util.UUID;
公共类MainActivity扩展了AppCompatActivity{
//将显示蓝牙打开、关闭或数据发送等状态
文本视图myLabel;
//将允许用户输入要打印的任何文本
编辑文本myTextbox;
//android内置蓝牙操作类
蓝牙适配器mBluetoothAdapter;
蓝牙插座;
蓝牙设备;
//需要与蓝牙设备/网络进行通信
输出流mmOutputStream;
输入流mmInputStream;
螺纹加工螺纹;
字节[]读取缓冲区;
int-readBufferPosition;
易变布尔工;
按钮打开按钮;
按钮发送按钮;
按钮关闭按钮;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
试一试{
//我们将有三个按钮用于特定功能
openButton=findViewById(R.id.open);
sendButton=findviewbyd(R.id.send);
closeButton=findViewById(R.id.close);
//文本标签和输入框
myLabel=(TextView)findViewById(R.id.label);
myTextbox=(EditText)findViewById(R.id.entry);
openButton.setOnClickListener(新视图.OnClickListener(){
公共void onClick(视图v){
试一试{
findBT();
openBT();
}捕获(IOEX异常){
例如printStackTrace();
}
}
});
}
捕获(例外e)
{
e、 printStackTrace();
}
//发送用户键入的要打印的数据
sendButton.setOnClickListener(新视图.OnClickListener(){
公共void onClick(视图v){
试一试{
sendData();
}捕获(IOEX异常){
例如printStackTrace();
}
}
});
//关闭蓝牙连接
closeButton.setOnClickListener(新视图.OnClickListener(){
公共void onClick(视图v){
试一试{
closeBT();
}捕获(IOEX异常){
例如printStackTrace();
}
}
});
}
私有void closeBT()引发IOException{
试一试{
stopWorker=true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
myLabel.setText(“蓝牙关闭”);
}捕获(例外e){
e、 printStackTrace();
}
}
//这将发送要由蓝牙打印机打印的文本数据
void sendData()引发IOException{
试一试{
//if(mmOutputStream==null){
//用户键入的文本
EditText myTextbox=(EditText)findViewById(R.id.entry);
字符串msg=myTextbox.getText().toString();
msg+=“\n”;
mmOutputStream=mmSocket.getOutputStream();
mmOutputStream.write(msg.getBytes());
//告诉用户数据已发送
setText(“已发送的数据”);
// }
}捕获(例外e){
e、 printStackTrace();
}
}
//尝试打开与蓝牙打印机设备的连接
void openBT()引发IOException{
试一试{
//标准SerialPortService ID
UUID UUID=UUID.fromString(“000011101-0000-1000-8000-00805f9b34fb”);
mmSocket=mmDevice.createRfcommSocketToServiceRecord(uuid);
mmSocket.connect();
mmOutputStream=mmSocket.getOutputStream();
mmInputStream=mmSocket.getInputStream();
beginListenForData();
myLabel.setText(“蓝牙打开”);
}捕获(例外e){
e、 printStackTrace();
}
}
/*
*打开与蓝牙打印机设备的连接后,
*我们必须倾听并检查是否发送了数据进行打印。
*/
void beginListenForData()
{
试一试{
最终处理程序=新处理程序();
//这是换行符的ASCII码
最后一个字节分隔符=10;
stopWorker=false;
readBufferPosition=0;
readBuffer=新字节[1024];
workerThread=新线程(new Runnable()){
公开募捐{
而(!Thread.currentThread().isInterrupted()&&!stopWorker){
试一试{
int bytesavable=mmInputStream.available();
如果(字节可用>0){
byte[]packetBytes=新字节[bytesAv]
void sendData() throws IOException {
try {
if(mmOutputStream==null) {
EditText myTextbox = (EditText) findViewById(R.id.entry);
String msg = myTextbox.getText().toString();
msg += "\n";
mmOutputStream = mmSocket.getOutputStream();
mmOutputStream.write(msg.getBytes());
Thread.sleep(100); // add this line
myLabel.setText("Data sent.");
}
} catch (Exception e) {
e.printStackTrace();
}
}
final String finalBILL = BILL;
Thread t = new Thread() {
public void run() {
try {
// This is printer specific code you can comment ==== > Start
mmOutputStream.write(finalBILL.getBytes());
Thread.sleep(100);
mmOutputStream.write(0x1D);
mmOutputStream.write(86);
mmOutputStream.write(48);
mmOutputStream.write(0);
// Clode BT
stopWorker = true;
mmOutputStream.close();
mmInputStream.close();
mmSocket.close();
} catch (Exception e) {
Log.e("MainActivity", "Exe ", e);
}
}
};
t.start();