Question

我有一个带有Icon的jLabel，我想用打印机（canon，hp，epson）打印一个按钮。我怎样才能做到这一点？任何有用的代码？代码段？链接？我能看到的就像这样： How to print content of a label in java?

但这不是我想要的。我正在使用netbeans 提前谢谢。

Answer 1

基本上，答案取决于标签是否显示在屏幕上。为确保标签（或实际上是任何组件）可以打印，首先必须正确尺寸......

可以使用setSize并在最基本级别提供getPreferredSize来完成此操作。

下一步是使用组件printAll方法（或print方法，根据您的需要）传递，这更适合...打印......因为它禁用双缓冲并赢得'当它没有附加到本地同伴时会产生讨厌的异常......

打印的示例为首选尺寸......

Normal

打印示例以填充可用区域...

Filled

现在，该示例使用printComponentToFile方法，但您希望使用printComponent方法将其实际打印到打印机，第一种方法对于执行页面预览和屏幕转储等操作非常有用。 ..

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.awt.print.PageFormat;
import java.awt.print.Paper;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JOptionPane;

public class PrintALabel {

    public static void main(String[] args) {
        try {
            JLabel label = new JLabel(
                    "This is a test",
                    new ImageIcon("path/to/image"),
                    JLabel.CENTER);
            printComponentToFile(label, true);
            printComponentToFile(label, false);
        } catch (PrinterException exp) {
            exp.printStackTrace();
        }
    }

    public static void printComponent(JComponent comp, boolean fill) throws PrinterException {
        PrinterJob pjob = PrinterJob.getPrinterJob();
        PageFormat pf = pjob.defaultPage();
        pf.setOrientation(PageFormat.LANDSCAPE);

        PageFormat postformat = pjob.pageDialog(pf);
        if (pf != postformat) {
            //Set print component
            pjob.setPrintable(new ComponentPrinter(comp, fill), postformat);
            if (pjob.printDialog()) {
                pjob.print();
            }
        }
    }

    public static void printComponentToFile(Component comp, boolean fill) throws PrinterException {
        Paper paper = new Paper();
        paper.setSize(8.3 * 72, 11.7 * 72);
        paper.setImageableArea(18, 18, 559, 783);

        PageFormat pf = new PageFormat();
        pf.setPaper(paper);
        pf.setOrientation(PageFormat.LANDSCAPE);

        BufferedImage img = new BufferedImage(
                (int) Math.round(pf.getWidth()),
                (int) Math.round(pf.getHeight()),
                BufferedImage.TYPE_INT_RGB);

        Graphics2D g2d = img.createGraphics();
        g2d.setColor(Color.WHITE);
        g2d.fill(new Rectangle(0, 0, img.getWidth(), img.getHeight()));
        ComponentPrinter cp = new ComponentPrinter(comp, fill);
        try {
            cp.print(g2d, pf, 0);
        } finally {
            g2d.dispose();
        }

        try {
            ImageIO.write(img, "png", new File("Page-" + (fill ? "Filled" : "") + ".png"));
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }

    public static class ComponentPrinter implements Printable {

        private Component comp;
        private boolean fill;

        public ComponentPrinter(Component comp, boolean fill) {
            this.comp = comp;
            this.fill = fill;
        }

        @Override
        public int print(Graphics g, PageFormat format, int page_index) throws PrinterException {

            if (page_index > 0) {
                return Printable.NO_SUCH_PAGE;
            }

            Graphics2D g2 = (Graphics2D) g;
            g2.translate(format.getImageableX(), format.getImageableY());

            double width = (int) Math.floor(format.getImageableWidth());
            double height = (int) Math.floor(format.getImageableHeight());

            if (!fill) {

                width = Math.min(width, comp.getPreferredSize().width);
                height = Math.min(height, comp.getPreferredSize().height);

            }

            comp.setBounds(0, 0, (int) Math.floor(width), (int) Math.floor(height));
            if (comp.getParent() == null) {
                comp.addNotify();
            }
            comp.validate();
            comp.doLayout();
            comp.printAll(g2);
            if (comp.getParent() != null) {
                comp.removeNotify();
            }

            return Printable.PAGE_EXISTS;
        }

    }

}

使用按钮在打印机中打印jLabel的图标

1 个答案: