使用 setVisible(false) 打印 JFrame

Question

我创建了一个带有 2 个 JFrame 窗口的 Swing 应用程序，我想将第一帧作为主页。我将第一帧中的打印按钮设置为打印第二帧。

如何使用frame.setVisible(false); 打印第二帧？我该如何解决？

我把我的代码放在下面：

package printuiwindow;

    /**
     *
     * @author Saravanan Ponnusamy
     */
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    import java.awt.print.*;

     class PrintUIWindow implements Printable, ActionListener {


    JFrame frameToPrint;

    public int print(Graphics g, PageFormat pf, int page) throws
                                                        PrinterException {

        if (page > 0) {
            return NO_SUCH_PAGE;
        }

        Graphics2D g2d = (Graphics2D)g;
        g2d.translate(pf.getImageableX(), pf.getImageableY()-55);

        frameToPrint.print(g);

        return PAGE_EXISTS;
    }

    public void actionPerformed(ActionEvent e) {
         PrinterJob job = PrinterJob.getPrinterJob();
         job.setPrintable(this);
         boolean ok = job.printDialog();
         if (ok) {
             try {
                  job.print();
             } catch (PrinterException ex) {
 System.out.println(ex);
             }
         }
    }

    public PrintUIWindow(JFrame f) {
        frameToPrint = f;
    }

    public static void main(String args[]) {
        UIManager.put("swing.boldMetal", Boolean.FALSE);
        JFrame f = new JFrame("Print UI Example");
        f.addWindowListener(new WindowAdapter() {
           public void windowClosing(WindowEvent e) {System.exit(0);}
        });
 //Printing frame design start


        JFrame frame = new JFrame("Print UI Example");
         JLabel label11=new JLabel("Selling Bill",JLabel.CENTER);
        JLabel label21=new JLabel("Customer Name :",JLabel.LEFT);
        JLabel label31=new JLabel("Buying Date :",JLabel.LEFT);
        JLabel label41=new JLabel("Book Buyed :",JLabel.LEFT);
        JLabel label51=new JLabel("Number :",JLabel.LEFT);
        JLabel label61=new JLabel("Total Price :",JLabel.LEFT);
         label11.setFont(new Font("Courier New", Font.BOLD, 13));
        label21.setFont(new Font("Courier New", Font.BOLD, 13));
        label31.setFont(new Font("Courier New", Font.BOLD, 13));
        label41.setFont(new Font("Courier New", Font.BOLD, 13));
        label51.setFont(new Font("Courier New", Font.BOLD, 13));
        label61.setFont(new Font("Courier New", Font.BOLD, 13));
 JPanel panel1=new JPanel();
 panel1.setLayout(new GridLayout(6,1));
        panel1.add(label11);
        panel1.add(label21);
        panel1.add(label31);
        panel1.add(label41);
        panel1.add(label51);
        panel1.add(label61);
        frame.setSize(300,300);
        frame.setLocationRelativeTo(null);
        frame.add(panel1,BorderLayout.CENTER);  
        panel1.setBackground(Color.WHITE);
        frame.setResizable(false);
        frame.setVisible(true);
    //printing frame design end    

//first frame design start
        JLabel label1=new JLabel("Selling Bill",JLabel.CENTER);
        JLabel label2=new JLabel("Customer Name :",JLabel.LEFT);
        JLabel label3=new JLabel("Buying Date :",JLabel.LEFT);
        JLabel label4=new JLabel("Book Buyed :",JLabel.LEFT);
        JLabel label5=new JLabel("Number :",JLabel.LEFT);
        JLabel label6=new JLabel("Total Price :",JLabel.LEFT);

        label1.setFont(new Font("Courier New", Font.BOLD, 13));
        label2.setFont(new Font("Courier New", Font.BOLD, 13));
        label3.setFont(new Font("Courier New", Font.BOLD, 13));
        label4.setFont(new Font("Courier New", Font.BOLD, 13));
        label5.setFont(new Font("Courier New", Font.BOLD, 13));
        label6.setFont(new Font("Courier New", Font.BOLD, 13));

        JButton printButton = new JButton("Print This Window");

        //print button code
        printButton.addActionListener(new PrintUIWindow(frame));
        JPanel panel=new JPanel();

        panel.setLayout(new GridLayout(6,1));
        panel.add(label1);
        panel.add(label2);
        panel.add(label3);
        panel.add(label4);
        panel.add(label5);
        panel.add(label6);
        f.setSize(300,300);
        f.setLocationRelativeTo(null);
        f.add(panel,BorderLayout.CENTER);
        f.add(printButton,BorderLayout.SOUTH);
        panel.setBackground(Color.WHITE);
        f.setResizable(false);
        f.setVisible(true);
    }
}

Answer 1

我多么讨厌打印组件，说真的，要么学会手工完成，要么使用 Jasper Reports 之类的东西。

你有一系列问题...

1. 组件只能有一个父级，因此当您创建第二个窗口并向其中添加组件时，您会将它们从第一个窗口中删除；
2. 您不能绘制不可见的组件；
3. 你真的不应该打印框架，最好打印面板；
4. 除非它已在屏幕上实现，否则您将负责确保在打印之前正确布局组件

您真的不想打印框架，您实际上想打印面板，它只是简单得多，而且您没有得到框架。如果您还想打印框架，则需要使框架可见。

所以，基于this previous answer

因此，基本上，这添加了一个简单的工厂方法来创建基本面板。这将创建此面板的两个实例，一个用于打印，一个用于显示（从技术上讲，您可以使用一个，但您明白了）。

打印过程将在打印时更新面板的布局，以确保其内容正确放置，以便实际呈现。

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import static java.awt.print.Printable.NO_SUCH_PAGE;
import static java.awt.print.Printable.PAGE_EXISTS;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;

class PrintUIWindow implements Printable, ActionListener {

    JPanel frameToPrint;
    boolean fill = false;

    public int print(Graphics g, PageFormat pf, int page) throws
                    PrinterException {

        if (page > 0) {
            return NO_SUCH_PAGE;
        }
        double width = (int) Math.floor(pf.getImageableWidth());
        double height = (int) Math.floor(pf.getImageableHeight());

        if (!fill) {

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

        }

        System.out.println(width + "x" + height);
        Graphics2D g2d = (Graphics2D) g;
        g2d.translate(pf.getImageableX(), pf.getImageableY());
        System.out.println(width + "x" + height);
        frameToPrint.setBounds(0, 0, (int) Math.floor(width), (int) Math.floor(height));
        if (frameToPrint.getParent() == null) {
            frameToPrint.addNotify();
        }
        frameToPrint.validate();
        frameToPrint.doLayout();
        frameToPrint.printAll(g2d);
        if (frameToPrint.getParent() != null) {
            frameToPrint.removeNotify();
        }

        return PAGE_EXISTS;
    }

    public void actionPerformed(ActionEvent e) {
        PrinterJob job = PrinterJob.getPrinterJob();
        job.setPrintable(this);
        boolean ok = job.printDialog();
        if (ok) {
            try {
                job.print();
            } catch (PrinterException ex) {
                System.out.println(ex);
            }
        }
    }

    public PrintUIWindow(JPanel f) {
        frameToPrint = f;
    }

    public static void forceLayout(JPanel panel) {
        if (panel.getParent() == null) {
            panel.addNotify();
        }
        panel.validate();
        panel.doLayout();
        if (panel.getParent() != null) {
            panel.removeNotify();
        }
    }

    public static JPanel makePanel() {
        JLabel label11 = new JLabel("Selling Bill", JLabel.LEFT);
        JLabel label21 = new JLabel("Customer Name :", JLabel.LEFT);
        JLabel label31 = new JLabel("Buying Date :", JLabel.LEFT);
        JLabel label41 = new JLabel("Book Buyed :", JLabel.LEFT);
        JLabel label51 = new JLabel("Number :", JLabel.LEFT);
        JLabel label61 = new JLabel("Total Price :", JLabel.LEFT);
        label11.setFont(new Font("Courier New", Font.BOLD, 13));
        label21.setFont(new Font("Courier New", Font.BOLD, 13));
        label31.setFont(new Font("Courier New", Font.BOLD, 13));
        label41.setFont(new Font("Courier New", Font.BOLD, 13));
        label51.setFont(new Font("Courier New", Font.BOLD, 13));
        label61.setFont(new Font("Courier New", Font.BOLD, 13));
        JPanel panel1 = new JPanel();
        panel1.setLayout(new GridLayout(6, 1));
        panel1.add(label11);
        panel1.add(label21);
        panel1.add(label31);
        panel1.add(label41);
        panel1.add(label51);
        panel1.add(label61);
        panel1.setBackground(Color.WHITE);
        return panel1;
    }

    public static void main(String args[]) {
        UIManager.put("swing.boldMetal", Boolean.FALSE);
        JFrame f = new JFrame("Print UI Example");

        JButton printButton = new JButton("Print This Window");

        JPanel toPrint = makePanel();
        System.out.println(toPrint.getPreferredSize());
        forceLayout(toPrint);
        System.out.println(toPrint.getPreferredSize());

        printButton.addActionListener(new PrintUIWindow(toPrint));
        JPanel panel = makePanel();
        f.add(panel, BorderLayout.CENTER);
        f.add(printButton, BorderLayout.SOUTH);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);

        System.out.println(panel.getPreferredSize());
        System.out.println(panel.getSize());
    }
}