java - 在没有打印服务预览的情况下打印

Question

我想在我的应用程序中按下按钮并将 pdf 文档发送到打印机以直接打印(不显示来自打印框架 Android 4.4 的系统 android 预览)。我该怎么做？我试图通过套接字连接到打印机。没问题，无一异常(exception)，但我的打印机没有响应，也没有打印任何东西。

也许我需要在手机上为具体打印机设置驱动程序？但是如何做到这一点以及我在哪里可以获得这样的驱动程序？

已编辑

Answer 1

我编写了一个类来帮助将 PDF 文件直接打印到网络打印机，并提供其 IP。它应该适用于大多数打印机，只要它们支持 PJL 命令。

public class PrintService {

    private static PrintListener printListener;

    public enum PaperSize {
        A4,
        A5
    }

    public static void printPDFFile(final String printerIP, final int printerPort,
                                    final File file, final String filename, final PaperSize paperSize, final int copies) {
        Thread t = new Thread(new Runnable() {
            @Override
            public void run() {
                Socket socket = null;
                DataOutputStream out = null;
                FileInputStream inputStream = null;
                try {
                    socket = new Socket(printerIP, printerPort);
                    out = new DataOutputStream(socket.getOutputStream());
                    DataInputStream input = new DataInputStream(socket.getInputStream());
                    inputStream = new FileInputStream(file);
                    byte[] buffer = new byte[3000];

                    final char ESC = 0x1b;
                    final String UEL = ESC + "%-12345X";
                    final String ESC_SEQ = ESC + "%-12345\r\n";

                    out.writeBytes(UEL);
                    out.writeBytes("@PJL \r\n");
                    out.writeBytes("@PJL JOB NAME = '" + filename + "' \r\n");
                    out.writeBytes("@PJL SET PAPER=" + paperSize.name());
                    out.writeBytes("@PJL SET COPIES=" + copies);
                    out.writeBytes("@PJL ENTER LANGUAGE = PDF\r\n");
                    while (inputStream.read(buffer) != -1)
                        out.write(buffer);
                    out.writeBytes(ESC_SEQ);
                    out.writeBytes("@PJL \r\n");
                    out.writeBytes("@PJL RESET \r\n");
                    out.writeBytes("@PJL EOJ NAME = '" + filename + "'");
                    out.writeBytes(UEL);

                    out.flush();
                } catch (IOException e) {
                    e.printStackTrace();
                    if (printListener != null)
                        printListener.networkError();
                } finally {
                    try {
                        if (inputStream != null)
                            inputStream.close();
                        if (out != null)
                            out.close();
                        if (socket != null)
                            socket.close();
                        if (printListener != null)
                            printListener.printCompleted();
                    } catch (IOException e) {
                        e.printStackTrace();
                        if (printListener != null)
                            printListener.networkError();
                    }
                }
            }
        });
        t.start();
    }

    public static void setPrintListener(PrintListener list) {
        printListener = list;
    }

    public interface PrintListener {
        void printCompleted();

        void networkError();
    }
}