Salve a tutti.
Sono un neofita di java e avrei una domanda banale.
Sto creando una piccola applicazione con NetBeans e nel codice sorgente ho incollato questa classe:
codice:
class Example3 {
//--- Private instances declarations
private final static int POINTS_PER_INCH = 72;
/**
* Constructor: Example3
*
*/
public Example3 () {
//--- Create a new PrinterJob object
PrinterJob printJob = PrinterJob.getPrinterJob ();
//--- Create a new book to add pages to
Book book = new Book ();
//--- Add the cover page using the default page format for this print job
book.append (new IntroPage (), printJob.defaultPage ());
//--- Add the document page using a landscape page format
PageFormat documentPageFormat = new PageFormat ();
documentPageFormat.setOrientation (PageFormat.LANDSCAPE);
book.append (new Document (), documentPageFormat);
//--- Add a third page using the same painter
book.append (new Document (), documentPageFormat);
//--- Tell the printJob to use the book as the pageable object
printJob.setPageable (book);
//--- Show the print dialog box. If the user click the
//--- print button we then proceed to print else we cancel
//--- the process.
if (printJob.printDialog()) {
try {
printJob.print();
} catch (Exception PrintException) {
PrintException.printStackTrace();
}
}
}
/**
* Class: IntroPage
*
* This class defines the painter for the cover page by implementing the
* Printable interface.
*
* @author Jean-Pierre Dube <jpdube@videotron.ca>
* @version 1.0
* @since 1.0
* @see Printable
*/
private class IntroPage implements Printable {
/**
* Method: print
*
* @param g a value of type Graphics
* @param pageFormat a value of type PageFormat
* @param page a value of type int
* @return a value of type int
*/
public int print (Graphics g, PageFormat pageFormat, int page) {
//--- Create the Graphics2D object
Graphics2D g2d = (Graphics2D) g;
//--- Translate the origin to 0,0 for the top left corner
g2d.translate (pageFormat.getImageableX (), pageFormat.getImageableY ());
//--- Set the default drawing color to black
g2d.setPaint (Color.black);
//--- Draw a border arround the page
Rectangle2D.Double border = new Rectangle2D.Double (0,
0,
pageFormat.getImageableWidth (),
pageFormat.getImageableHeight ());
g2d.draw (border);
//--- Print the title
String titleText = "Printing in Java Part 2";
Font titleFont = new Font ("helvetica", Font.BOLD, 36);
g2d.setFont (titleFont);
//--- Compute the horizontal center of the page
FontMetrics fontMetrics = g2d.getFontMetrics ();
double titleX = (pageFormat.getImageableWidth () / 2) - (fontMetrics.stringWidth (titleText) / 2);
double titleY = 3 * POINTS_PER_INCH;
g2d.drawString (titleText, (int) titleX, (int) titleY);
return (PAGE_EXISTS);
}
}
/**
* Class: Document
*
* This class is the painter for the document content.
*
*
* @author Jean-Pierre Dube <jpdube@videotron.ca>
* @version 1.0
* @since 1.0
* @see Printable
*/
private class Document implements Printable {
/**
* Method: print
*
* @param g a value of type Graphics
* @param pageFormat a value of type PageFormat
* @param page a value of type int
* @return a value of type int
*/
public int print (Graphics g, PageFormat pageFormat, int page) {
//--- Create the Graphics2D object
Graphics2D g2d = (Graphics2D) g;
//--- Translate the origin to 0,0 for the top left corner
g2d.translate (pageFormat.getImageableX (), pageFormat.getImageableY ());
//--- Set the drawing color to black
g2d.setPaint (Color.black);
//--- Draw a border arround the page using a 12 point border
g2d.setStroke (new BasicStroke (12));
Rectangle2D.Double border = new Rectangle2D.Double (0,
0,
pageFormat.getImageableWidth (),
pageFormat.getImageableHeight ());
g2d.draw (border);
//--- Print page 1
if (page == 1) {
//--- Print the text one inch from the top and laft margins
g2d.drawString ("This the content page of page: " + page, POINTS_PER_INCH, POINTS_PER_INCH);
return (PAGE_EXISTS);
}
//--- Print page 2
else if (page == 2) {
//--- Print the text one inch from the top and laft margins
g2d.drawString ("This the content of the second page: " + page, POINTS_PER_INCH, POINTS_PER_INCH);
return (PAGE_EXISTS);
}
//--- Validate the page
return (NO_SUCH_PAGE);
}
}
} // Example3
Come faccio a richiamarla di un pulsante JButton?
grazie in anticipo dell'aiuto