Printing with Zebra Link-Os SDK

Question

I am using this code to print an image to a zebra printer.

ZebraPrinterConnection connection = new TcpPrinterConnection(ipAddress,port);
connection.Open();
ZebraPrinter printer = ZebraPrinterFactory.GetInstance(connection);
printer.GetGraphicsUtil().PrintImage("imageAddress");

It works fine but some times the printer doesn't print and in the code I dont get any errors. Is there a way to check if physically the label was printed?

Answer 1

There are a couple of ways to do this.

First way is to check the status during/after you print and confirm there are no bytes in the buffer and no error on the printer:

private boolean postPrintCheckPrinterStatus(Connection connection)
{
    ZebraPrinter printer = ZebraPrinterFactory.getInstance(PrinterLanguage.ZPL, connection);
    PrinterStatus printerStatus = printer.getCurrentStatus();

    // loop while printing until print is complete or there is an error
    while ((printerStatus.numberOfFormatsInReceiveBuffer > 0) && (printerStatus.isReadyToPrint))
    {
        printerStatus = printer.getCurrentStatus();
    }
    if (printerStatus.isReadyToPrint) {
        System.out.println("Ready To Print");
        return true;
     } else if (printerStatus.isPaused) {
        System.out.println("Cannot Print because the printer is paused.");
     } else if (printerStatus.isHeadOpen) {
        System.out.println("Cannot Print because the printer head is open.");
     } else if (printerStatus.isPaperOut) {
        System.out.println("Cannot Print because the paper is out.");
     } else {
        System.out.println("Cannot Print.");
     }
    return false;
}

The other way to check this would be to use the printer odometer to ensure the label was printed. Check the odometer before and then again after:

// Set settings, check status, print, etc.
        if (setPrintLanguage(statusConnection) && checkPrinterStatus(statusConnection))
        {
            int labelCount = Integer.parseInt(SGD.GET("odometer.total_label_count", statusConnection));
            // Send Print Job (1 label)
            String zplData = "^XA^FO20,20^A0N,25,25^FDThis is a ZPL test.^FS^XZ";
            printerConnection.write(zplData.getBytes());

            if (postPrintCheckPrinterStatus(statusConnection))
            {
                int newLabelCount = Integer.parseInt(SGD.GET("odometer.total_label_count", statusConnection));
                if (newLabelCount == labelCount + 1)
                {
                    System.out.println("Print Successful.");
                }
            }
            //else reprint?
        }