So, the first thing we need to is make sure that the component been printed is at it's preferred size...
component.setSize(component.getPreferredSize());
This is important, but also remember, that this will affect the component that is on the screen...
Next, we need to work out if we are printing a new page or re-printing the current page. This occurs because print
might be called multiple times for a given page...
if (lastPage != pageIndex) {
lastPage = pageIndex;
//...
}
We then need to calculate the y offset of the component that fits the current page...
yOffset = height * pageIndex;
if (yOffset > component.getHeight()) {
yOffset = -1;
}
If the yOffset
is greater then the component
height, then we don't want to print any more pages.
Next, we print the page, to do this, we need to translate the Graphics
context so that the yOffset
becomes the new 0
position...
g2d.translate(0, -yOffset);
Then we print the component...
component.printAll(g2d);
For example...
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.awt.print.PageFormat;
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.print.attribute.HashPrintRequestAttributeSet;
import javax.print.attribute.PrintRequestAttributeSet;
import javax.print.attribute.standard.MediaSizeName;
import javax.print.attribute.standard.PrinterResolution;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.Scrollable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class PrintMe {
public static void main(String[] args) {
new PrintMe();
}
public PrintMe() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
TestPane testPane = new TestPane();
JButton btn = new JButton("Print");
btn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
aset.add(MediaSizeName.ISO_A4);
aset.add(new PrinterResolution(300, 300, PrinterResolution.DPI));
PrinterJob pj = PrinterJob.getPrinterJob();
pj.setPrintable(new MultiPagePrintable(testPane));
if (pj.printDialog(aset)) {
try {
pj.print(aset);
testPane.getParent().invalidate();
testPane.getParent().validate();
} catch (PrinterException ex) {
ex.printStackTrace();
}
}
}
});
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new JScrollPane(testPane));
frame.add(btn, BorderLayout.SOUTH);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel implements Scrollable {
private BufferedImage img;
public TestPane() {
try {
img = ImageIO.read(new File("Get your own image"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
@Override
public Dimension getPreferredSize() {
return img == null ? new Dimension(200, 200) : new Dimension(img.getWidth(), img.getHeight());
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (img != null) {
Graphics2D g2d = (Graphics2D) g.create();
int x = (getWidth() - img.getWidth()) / 2;
int y = (getHeight() - img.getHeight()) / 2;
g2d.drawImage(img, x, y, this);
g2d.dispose();
}
}
@Override
public Dimension getPreferredScrollableViewportSize() {
return new Dimension(200, 200);
}
@Override
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction) {
return 128;
}
@Override
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction) {
return 128;
}
@Override
public boolean getScrollableTracksViewportWidth() {
return false;
}
@Override
public boolean getScrollableTracksViewportHeight() {
return false;
}
}
public class MultiPagePrintable implements Printable {
private JComponent component;
private int lastPage = 0;
private double yOffset;
public MultiPagePrintable(JComponent component) {
this.component = component;
}
@Override
public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
int result = NO_SUCH_PAGE;
double height = pageFormat.getImageableHeight();
component.setSize(component.getPreferredSize());
if (lastPage != pageIndex) {
lastPage = pageIndex;
yOffset = height * pageIndex;
if (yOffset > component.getHeight()) {
yOffset = -1;
}
}
if (yOffset >= 0) {
Graphics2D g2d = (Graphics2D) graphics;
g2d.translate((int) pageFormat.getImageableX(),
(int) pageFormat.getImageableY());
g2d.translate(0, -yOffset);
component.printAll(g2d);
result = PAGE_EXISTS;
}
return result;
}
}
}
Now, this example only prints in the vertical direction, if you need it to print the horizontal direction as well, it gets a little more complicated, but that the basic concept remains the same