我正在 Android 中编写一个简单的应用程序以通过 ESC/POS 热敏打印机进行打印。我只是有问题。该应用程序生成一个二维码(带有 zxing 库),将其转换为位图并将其发送到打印机。打印机打印它,但我无法居中。相反,我没有定位问题。
这是打印文本和二维码的代码。
byte[] INIT = {27, 64};
byte[] FEED_LINE = {10};
byte[] SELECT_FONT_A = {27, 33, 0};
byte[] FONT_B = {0x1B, 0x4D, 0x01};
byte[] ALLINEA_SX = {0x1B, 0x61, 0x00};
byte[] ALLINEA_CT = {0x1B, 0x61, 0x01};
byte[] ALLINEA_DX = {0x1B, 0x61, 0x02};
byte[] GRASSETTO_ON = {0x1B, 0x47, 0x11};
byte[] GRASSETTO_OFF = {0x1B, 0x47, 0x00};
byte[] SET_6 = {0x1B, 0x52, 0x06};
byte[] CODICI = {0x1B, 0x74, 0x13};
byte[] EURO = {(byte) 0xD5};
byte[] PALLINO = {(byte) 0x5B};
byte[] FONT_3X = {0x1D, 0x21, 0x21};
byte[] FONT_2X = {0x1D, 0x21, 0x11};
byte[] FONT_1X = {0x1D, 0x21, 0x00};
byte[] SET_BAR_CODE_HEIGHT = {29, 104, 100};
byte[] PRINT_BAR_CODE_1 = {29, 107, 2};
byte[] SEND_NULL_BYTE = {0x00};
byte[] SELECT_PRINT_SHEET = {0x1B, 0x63, 0x30, 0x02};
byte[] FEED_PAPER_AND_CUT = {0x1D, 0x56, 66, 0x00};
byte[] SELECT_CYRILLIC_CHARACTER_CODE_TABLE = {0x1B, 0x74, 0x11};
byte[] SELECT_BIT_IMAGE_MODE = {0x1B, 0x2A, 33, 127, 3};
byte[] SET_LINE_SPACING_24 = {0x1B, 0x33, 24};
byte[] SET_LINE_SPACING_30 = {0x1B, 0x33, 30};
byte[] TRANSMIT_DLE_PRINTER_STATUS = {0x10, 0x04, 0x01};
byte[] TRANSMIT_DLE_OFFLINE_PRINTER_STATUS = {0x10, 0x04, 0x02};
byte[] TRANSMIT_DLE_ERROR_STATUS = {0x10, 0x04, 0x03};
byte[] TRANSMIT_DLE_ROLL_PAPER_SENSOR_STATUS = {0x10, 0x04, 0x04};
mService.write(INIT);
mService.write(ALLINEA_CT); //text to center
mService.write(SELECT_FONT_A);
mService.write(FONT_2X);
mService.write("Hello stackoverflow!!\n".getBytes());
mService.write(FONT_1X);
mService.write(ALLINEA_SX); //text to left
mService.write("Thanks for help!\n".getBytes());
int QRCODE_IMAGE_HEIGHT = 255;
int QRCODE_IMAGE_WIDTH = 255;
QRCodeWriter qrWriter = new QRCodeWriter();
try {
Hashtable<EncodeHintType, ErrorCorrectionLevel> hints = new Hashtable<EncodeHintType, ErrorCorrectionLevel>();
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
BitMatrix bitMatrix = qrWriter.encode("https://stackoverflow.com",
BarcodeFormat.QR_CODE,
QRCODE_IMAGE_WIDTH,
QRCODE_IMAGE_HEIGHT, hints);
int bitMatrixWidth = bitMatrix.getWidth();
int bitMatrixHeight = bitMatrix.getHeight();
int[] pixels = new int[bitMatrixWidth * bitMatrixHeight];
for (int y = 0; y < bitMatrixHeight; y++) {
int offset = y * bitMatrixWidth;
for (int x = 0; x < bitMatrixWidth; x++) {
pixels[offset + x] = bitMatrix.get(x, y) ?
getResources().getColor(R.color.QRCodeBlackColor):getResources().getColor(R.color.QRCodeWhiteColor);
}
}
Bitmap bitmap = Bitmap.createBitmap(bitMatrixWidth, bitMatrixHeight, Bitmap.Config.ARGB_4444);
bitmap.setPixels(pixels, 0, 255, 0, 0, bitMatrixWidth, bitMatrixHeight);
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.k_city5);
Bitmap bmOverlay = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), bitmap.getConfig());
Canvas canvas = new Canvas(bmOverlay);
canvas.drawBitmap(bitmap, new Matrix(), null);
canvas.drawBitmap(bmp, 94, 94, null); //34x34
//canvas.drawBitmap(bmp, 86, 86, null); //42x42
if(bmOverlay!=null) {
byte[] command = Utils.decodeBitmap(bmOverlay);
mService.write(ALLINEA_CT); //This command should center my QR, but it's not working
mService.write(command);
mService.write(FEED_LINE);
mService.write(FEED_LINE);
}