printrequestattributeset - java print example

Ajustar/Escalar JComponent a la página que se está imprimiendo

Question

Estoy intentando escalar mi componente para que pueda caber en una sola página impresa (retrato o paisaje)

 gDiagram.getComponent()

es el componente (JPanel) que intento imprimir.

Esto es lo que he basado hasta ahora en ¿Cómo puedo imprimir el contenido de un solo JPanel?

/**
* Prints the diagram.
*/
public void printDiagram() {
PrinterJob pj = PrinterJob.getPrinterJob();
pj.setJobName(" Print Component ");
pj.setPrintable(new Printable() {
@Override
public int print(Graphics g, PageFormat pf, int pageNumber)
throws PrinterException {
// TODO Auto-generated method stub
if (pageNumber > 0) {
return Printable.NO_SUCH_PAGE;
}
Graphics2D g2 = (Graphics2D) g;
g2.translate(pf.getImageableX(), pf.getImageableY());
double sx = pf.getImageableWidth() / gDiagram.getComponent().getWidth();
double sy = pf.getImageableHeight() / gDiagram.getComponent().getHeight();
gDiagram.getComponent().paint(g2);
g2.scale(sx, sy);
return Printable.PAGE_EXISTS;
}
});
if (!pj.printDialog()) {
return;
}
try {
pj.print();
} catch (PrinterException ex) {
System.out.println(ex);
}
}

No estoy muy familiarizado con los gráficos, por lo que cualquier ayuda sería apreciada

Answer 1

El concepto básico es usar una AffineTransformation para proporcionar escalado al resultado resultante.

En mis pruebas, pude tomar una imagen de 7680x4800 y obtener una impresión en una página de 595x842 (reducida en un 93%)

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.AffineTransform;
import java.awt.geom.Dimension2D;
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 java.text.NumberFormat;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class PrintTest {
public static void main(String[] args) {
new PrintTest();
}
public PrintTest() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
final TestPane imagePane = new TestPane();
JButton print = new JButton("Print");
print.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
printComponent(imagePane);
}
});
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(imagePane);
frame.add(print, BorderLayout.SOUTH);
frame.setSize(200, 200);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage bg;
public TestPane() {
try {
bg = ImageIO.read(new File("path/to/a/image"));
} catch (IOException ex) {
Logger.getLogger(PrintTest.class.getName()).log(Level.SEVERE, null, ex);
}
}
@Override
public Dimension getPreferredSize() {
return bg == null ? new Dimension(200, 200) : new Dimension(bg.getWidth(), bg.getHeight());
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (bg != null) {
int x = (getWidth() - bg.getWidth()) / 2;
int y = (getHeight() - bg.getHeight()) / 2;
g2d.drawImage(bg, x, y, this);
}
g2d.dispose();
}
}
public void printComponent(Component comp) {
PrinterJob pj = PrinterJob.getPrinterJob();
pj.setJobName(" Print Component ");
pj.setPrintable(new ComponentPrintable(comp));
if (!pj.printDialog()) {
return;
}
try {
pj.print();
} catch (PrinterException ex) {
System.out.println(ex);
}
}
public class ComponentPrintable implements Printable {
private Component comp;
private ComponentPrintable(Component comp) {
this.comp = comp;
}
@Override
public int print(Graphics g, PageFormat pf, int pageNumber)
throws PrinterException {
// TODO Auto-generated method stub
if (pageNumber > 0) {
return Printable.NO_SUCH_PAGE;
}
// Get the preferred size ofthe component...
Dimension compSize = comp.getPreferredSize();
// Make sure we size to the preferred size
comp.setSize(compSize);
// Get the the print size
Dimension printSize = new Dimension();
printSize.setSize(pf.getImageableWidth(), pf.getImageableHeight());
// Calculate the scale factor
double scaleFactor = getScaleFactorToFit(compSize, printSize);
// Don''t want to scale up, only want to scale down
if (scaleFactor > 1d) {
scaleFactor = 1d;
}
// Calcaulte the scaled size...
double scaleWidth = compSize.width * scaleFactor;
double scaleHeight = compSize.height * scaleFactor;
// Create a clone of the graphics context. This allows us to manipulate
// the graphics context without begin worried about what effects
// it might have once we''re finished
Graphics2D g2 = (Graphics2D) g.create();
// Calculate the x/y position of the component, this will center
// the result on the page if it can
double x = ((pf.getImageableWidth() - scaleWidth) / 2d) + pf.getImageableX();
double y = ((pf.getImageableHeight() - scaleHeight) / 2d) + pf.getImageableY();
// Create a new AffineTransformation
AffineTransform at = new AffineTransform();
// Translate the offset to out "center" of page
at.translate(x, y);
// Set the scaling
at.scale(scaleFactor, scaleFactor);
// Apply the transformation
g2.transform(at);
// Print the component
comp.printAll(g2);
// Dispose of the graphics context, freeing up memory and discarding
// our changes
g2.dispose();
comp.revalidate();
return Printable.PAGE_EXISTS;
}
}
public static double getScaleFactorToFit(Dimension original, Dimension toFit) {
double dScale = 1d;
if (original != null && toFit != null) {
double dScaleWidth = getScaleFactor(original.width, toFit.width);
double dScaleHeight = getScaleFactor(original.height, toFit.height);
dScale = Math.min(dScaleHeight, dScaleWidth);
}
return dScale;
}
public static double getScaleFactor(int iMasterSize, int iTargetSize) {
double dScale = 1;
if (iMasterSize > iTargetSize) {
dScale = (double) iTargetSize / (double) iMasterSize;
} else {
dScale = (double) iTargetSize / (double) iMasterSize;
}
return dScale;
}
}