您好我是Android新手我花了很多时间试图在我的应用程序中打印收据 . 我使用 Zicox XT4131 热敏打印机 connects via bluetooth 到我的平板电脑上运行 Android 4.4 OS .
到目前为止，我已经成功地只能在我的收据上打印文字，现在我的下一个障碍是试图在我的收据上打印条形码，qrcodes和徽标，我花了很多时间在互联网上试图找到解决方案，但似乎没什么上班 .
然而，我学到的是要打印位图图像，我首先需要将其转换为字节数组（我做了）并将其写入输出流（我也做过），之后我得到的全部是打印机上的长空格或一些奇怪的字符 .
现在我拒绝相信2016年从平板电脑到打印机的打印没有简单的解决方案所以我只假设我正在以错误的方式解决这个问题 .
我的应用程序的工作方式很简单，在我的活动中，我有一个购买预览，有一个按钮，点击后发送命令到蓝牙打印机打印 . 这就是全部，没有转换为pdf，什么不转换，必须选择打印机 .
所以我想知道的是，从我的平板电脑到我的蓝牙打印机正确打印收据的方式到底是什么方式我将如何使用这种方法打印条形码，qrcode或徽标以及收据上的文字？
我不希望将其作为主题投票，因为这可能要求我放弃这个项目（所有因为打印）我只想要一个可行的有效解决方案，可以帮助我做我想做的事情 .
这是我现在打印的代码：
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.os.Handler;
import android.view.View;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.util.EnumMap;
import java.util.GregorianCalendar;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
这些是它的功能：
// this will find a bluetooth printer device
void findBT() {
try {
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(mBluetoothAdapter == null) {
Toast.makeText(PurchaseSummaryActivity.this, "No bluetooth adapter available", Toast.LENGTH_SHORT).show();
}
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.getName().equals("XT4131A")) {
mDevice = device;
break;
}
}
}
Toast.makeText(PurchaseSummaryActivity.this, "Bluetooth device found.", Toast.LENGTH_SHORT).show();
}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");
mSocket = mDevice.createRfcommSocketToServiceRecord(uuid);
mSocket.connect();
mOutputStream = mSocket.getOutputStream();
mInputStream = mSocket.getInputStream();
beginListenForData();
Toast.makeText(PurchaseSummaryActivity.this, "Bluetooth Connection Opened", Toast.LENGTH_SHORT).show();
} 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 = mInputStream.available();
if (bytesAvailable > 0) {
byte[] packetBytes = new byte[bytesAvailable];
mInputStream.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() {
Toast.makeText(PurchaseSummaryActivity.this, data, Toast.LENGTH_SHORT).show();
}
});
} else {
readBuffer[readBufferPosition++] = b;
}
}
}
} catch (IOException ex) {
stopWorker = true;
}
}
}
});
workerThread.start();
} catch (Exception e) {
e.printStackTrace();
}
}
// this will send text data to be printed by the bluetooth printer
void printTickets(Event eo, Cart.Ticket to) throws IOException {
try {
byte[] arrayOfByte1 = { 27, 33, 0 };
byte[] format = { 27, 33, 0 };
// Bold
format[2] = ((byte)(0x8 | arrayOfByte1[2]));
// Height
format[2] = ((byte)(0x10 | arrayOfByte1[2]));
// Width
format[2] = ((byte) (0x20 | arrayOfByte1[2]));
byte[] center = new byte[]{ 0x1b, 0x61, 0x01 };
// the text typed by the user
StringBuilder msg = new StringBuilder();
msg.append("\n");
msg.append("\n");
msg.append("\n myTicketGH");
mOutputStream.write(center);
mOutputStream.write(format);
mOutputStream.write(msg.toString().getBytes());
// Bold
format[2] = ((byte)(0x8 | arrayOfByte1[2]));
msg = new StringBuilder();
msg.append("\n Address: No 10, Otublohum street");
msg.append("\n North Industrial Area");
msg.append("\n Tel.: 0266 8888 64");
msg.append("\n");
msg.append("\n");
msg.append("\n");
mOutputStream.write(center);
mOutputStream.write(format);
mOutputStream.write(msg.toString().getBytes());
// Bold
format[2] = ((byte)(0x8 | arrayOfByte1[2]));
byte[] left = new byte[]{ 0x1b, 0x61, 0x00 };
msg = new StringBuilder();
msg.append("\n Event");
mOutputStream.write(format);
mOutputStream.write(left);
mOutputStream.write(msg.toString().getBytes());
mOutputStream.write(arrayOfByte1);
left = new byte[]{ 0x1b, 0x61, 0x00 };
msg = new StringBuilder();
msg.append("\n Name : " + eo.getName());
msg.append("\n Date : " + eo.getDate());
msg.append("\n Time : " + eo.getTime());
msg.append("\n Venue : " + eo.getVenue());
msg.append("\n");
msg.append("\n");
mOutputStream.write(arrayOfByte1);
mOutputStream.write(left);
mOutputStream.write(msg.toString().getBytes());
// Bold
format[2] = ((byte)(0x8 | arrayOfByte1[2]));
msg = new StringBuilder();
msg.append("\n Ticket");
mOutputStream.write(format);
mOutputStream.write(left);
mOutputStream.write(msg.toString().getBytes());
mOutputStream.write(arrayOfByte1);
left = new byte[]{ 0x1b, 0x61, 0x00 };
msg = new StringBuilder();
msg.append("\n Code : " + to.getCode());
msg.append("\n Class : " + to.getTclass() );
msg.append("\n Fee : " + to.getPrice());
msg.append("\n Seat : " + "N / A");
msg.append("\n Date of Purchase : " + Calendar.getInstance().getTime().toString());
msg.append("\n");
msg.append("\n");
msg.append("\n");
msg.append("\n");
msg.append("\n");
mOutputStream.write(arrayOfByte1);
mOutputStream.write(left);
mOutputStream.write(msg.toString().getBytes());
// barcode data
String barcode_data = "123456";
// barcode image
byte[] barCodeBytes;
String barCodeHex = "";
try {
barCode = encodeAsBitmap(barcode_data, BarcodeFormat.CODE_128, 300, 40);
barCode = bitmapToGrayscale(barCode);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
barCodeBytes = stream.toByteArray();
mOutputStream.write(barCodeBytes);
} catch (WriterException e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
}
// close the connection to bluetooth printer.
void closeBT() throws IOException {
try {
stopWorker = true;
mOutputStream.close();
mInputStream.close();
mSocket.close();
// myLabel.setText("Bluetooth Closed");
} catch (Exception e) {
e.printStackTrace();
}
}
这是我的onClickEvent处理程序：
this.buttonNextView.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
try {
findBT();
openBT();
for (int i = 0; i < ta.length(); i++)
{
try {
printTickets(eo, new Cart(). new Ticket(
ta.getJSONObject(i).getInt("id"),
ta.getJSONObject(i).getString("code"),
ta.getJSONObject(i).getString("class"),
ta.getJSONObject(i).getString("description"),
Float.parseFloat(ta.getJSONObject(i).getString("price")),
ta.getJSONObject(i).getInt("quantity")
));
} catch (JSONException e) {
e.printStackTrace();
}
}
closeBT();
} catch (IOException ex) {
ex.printStackTrace();
}
}
});
是的，我使用的打印机能够打印条形码和二维码 .