Se puoi provalo è fammi sapere
CLASSE VISTA
/*
* Vista.java
*
* Created on 24 ottobre 2004, 11.21
*/
package javaapplication4;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Point2D;
import java.awt.print.Pageable;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
/**
* A simple Pageable class that can
* split a large drawing canvas over multiple
* pages.
*
* The pages in a canvas are laid out on
* pages going left to right and then top
* to bottom.
*/
public class Vista implements Pageable {
private int mNumPagesX;
private int mNumPagesY;
private int mNumPages;
private Printable mPainter;
private PageFormat mFormat;
/**
* Create a java.awt.Pageable that will print
* a canvas over as many pages as are needed.
* A Vista can be passed to PrinterJob.setPageable.
*
* @param width The width, in 1/72nds of an inch,
* of the vist's canvas.
*
* @param height The height, in 1/72nds of an inch,
* of the vista's canvas.
*
* @param painter The object that will drawn the contents
* of the canvas.
*
* @param format The description of the pages on to which
* the canvas will be drawn.
*/
public Vista(float width, float height, Printable painter, PageFormat format) {
setPrintable(painter);
setPageFormat(format);
setSize(width, height);
}
/**
* Create a vista over a canvas whose width and height
* are zero and whose Printable and PageFormat are null.
*/
protected Vista() {
}
/**
* Set the object responsible for drawing the canvas.
*/
protected void setPrintable(Printable painter) {
mPainter = painter;
}
/**
* Set the page format for the pages over which the
* canvas will be drawn.
*/
protected void setPageFormat(PageFormat pageFormat) {
mFormat = pageFormat;
}
/**
* Set the size of the canvas to be drawn.
*
* @param width The width, in 1/72nds of an inch, of
* the vist's canvas.
*
* @param height The height, in 1/72nds of an inch, of
* the vista's canvas.
*/
protected void setSize(float width, float height) {
mNumPagesX = (int) ((width + mFormat.getImageableWidth() - 1)/ mFormat.getImageableWidth());
mNumPagesY = (int) ((height + mFormat.getImageableHeight() - 1)/ mFormat.getImageableHeight());
mNumPages = mNumPagesX * mNumPagesY;
}
/**
* Returns the number of pages over which the canvas
* will be drawn.
*/
public int getNumberOfPages() {
return mNumPages;
}
protected PageFormat getPageFormat() {
return mFormat;
}
/**
* Returns the PageFormat of the page specified by
* pageIndex. For a Vista the PageFormat
* is the same for all pages.
*
* @param pageIndex the zero based index of the page whose
* PageFormat is being requested
* @return the PageFormat describing the size and
* orientation.
* @exception IndexOutOfBoundsException
* the Pageable does not contain the requested
* page.
*/
public PageFormat getPageFormat(int pageIndex) throws IndexOutOfBoundsException {
if (pageIndex >= mNumPages) {
throw new IndexOutOfBoundsException();
}
return getPageFormat();
}
/**
* Returns the <code>Printable</code> instance responsible for
* rendering the page specified by <code>pageIndex</code>.
* In a Vista, all of the pages are drawn with the same
* Printable. This method however creates
* a Printable which calls the canvas's
* Printable. This new Printable
* is responsible for translating the coordinate system
* so that the desired part of the canvas hits the page.
*
* The Vista's pages cover the canvas by going left to
* right and then top to bottom. In order to change this
* behavior, override this method.
*
* @param pageIndex the zero based index of the page whose
* Printable is being requested
* @return the Printable that renders the page.
* @exception IndexOutOfBoundsException
* the Pageable does not contain the requested
* page.
*/
public Printable getPrintable(int pageIndex) throws IndexOutOfBoundsException {
if (pageIndex >= mNumPages) {
throw new IndexOutOfBoundsException();
}
double originX = (pageIndex % mNumPagesX) * mFormat.getImageableWidth();
double originY = (pageIndex / mNumPagesX) * mFormat.getImageableHeight();
Point2D.Double origin = new Point2D.Double(originX, originY);
return new TranslatedPrintable(mPainter, origin);
}
/**
* This inner class's sole responsibility is to translate
* the coordinate system before invoking a canvas's
* painter. The coordinate system is translated in order
* to get the desired portion of a canvas to line up with
* the top of a page.
*/
public static final class TranslatedPrintable implements Printable {
/**
* The object that will draw the canvas.
*/
private Printable mPainter;
/**
* The upper-left corner of the part of the canvas
* that will be displayed on this page. This corner
* is lined up with the upper-left of the imageable
* area of the page.
*/
private Point2D mOrigin;
/**
* Create a new Printable that will translate
* the drawing done by painter on to the
* imageable area of a page.
*
* @param painter The object responsible for drawing
* the canvas
*
* @param origin The point in the canvas that will be
* mapped to the upper-left corner of
* the page's imageable area.
*/
public TranslatedPrintable(Printable painter, Point2D origin) {
mPainter = painter;
mOrigin = origin;
}
/**
* Prints the page at the specified index into the specified
* {@link Graphics} context in the specified
* format. A PrinterJob calls the
* Printableinterface to request that a page be
* rendered into the context specified by
* graphics. The format of the page to be drawn is
* specified by pageFormat. The zero based index
* of the requested page is specified by pageIndex.
* If the requested page does not exist then this method returns
* NO_SUCH_PAGE; otherwise PAGE_EXISTS is returned.
* The Graphics class or subclass implements the
* {@link PrinterGraphics} interface to provide additional
* information. If the Printable object
* aborts the print job then it throws a {@link PrinterException}.
* @param graphics the context into which the page is drawn
* @param pageFormat the size and orientation of the page being drawn
* @param pageIndex the zero based index of the page to be drawn
* @return PAGE_EXISTS if the page is rendered successfully
* or NO_SUCH_PAGE if pageIndex specifies a
* non-existent page.
* @exception java.awt.print.PrinterException
* thrown when the print job is terminated.
*/
public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
Graphics2D g2 = (Graphics2D) graphics;
g2.translate(-mOrigin.getX(), -mOrigin.getY());
mPainter.print(g2, pageFormat, 1);
return PAGE_EXISTS;
}
}
}
Rispondi quotando