Posted on 2007-07-12 19:10
kooyee 阅读(1502)
评论(0) 编辑 收藏 所属分类:
GUI骨衣
//Send questions, comments, bug reports, etc. to the authors:

//Rob Warner (rwarner@interspatial.com)
//Robert Harris (rbrt_harris@yahoo.com)

import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.printing.*;
import org.eclipse.swt.widgets.*;


/** *//**
* This class demonstrates printing images
*/

public class ImagePrinterExample
{

/** *//**
* The application entry point
* @param args the command line arguments
*/

public static void main(String[] args)
{
Display display = new Display();
Shell shell = new Shell(display, SWT.NONE);


try
{
// Prompt the user for an image file
FileDialog fileChooser = new FileDialog(shell, SWT.OPEN);
String fileName = fileChooser.open();


if (fileName == null)
{ return; }

// Load the image
ImageLoader loader = new ImageLoader();
ImageData[] imageData = loader.load(fileName);


if (imageData.length > 0)
{
// Show the Choose Printer dialog
PrintDialog dialog = new PrintDialog(shell, SWT.NULL);
PrinterData printerData = dialog.open();


if (printerData != null)
{
// Create the printer object
Printer printer = new Printer(printerData);
// Calculate the scale factor between the screen resolution and printer
// resolution in order to correctly size the image for the printer
Point screenDPI = display.getDPI();
Point printerDPI = printer.getDPI();
int scaleFactor = printerDPI.x / screenDPI.x;
// Determine the bounds of the entire area of the printer
Rectangle trim = printer.computeTrim(0, 0, 0, 0);

// Start the print job

if (printer.startJob(fileName))
{

if (printer.startPage())
{
GC gc = new GC(printer);
Image printerImage = new Image(printer, imageData[0]);
// Draw the image
gc.drawImage(printerImage, 0, 0, imageData[0].width,
imageData[0].height, -trim.x, -trim.y,
scaleFactor * imageData[0].width,
scaleFactor * imageData[0].height);
// Clean up
printerImage.dispose();
gc.dispose();
printer.endPage();
}
}
// End the job and dispose the printer
printer.endJob();
printer.dispose();
}
}

} catch (Exception e)
{
MessageBox messageBox = new MessageBox(shell, SWT.ICON_ERROR);
messageBox.setMessage("Error printing test image");
messageBox.open();
}
}
}

和打印文字不同。因为系统中的dpi(dot per inch)和打印机的dpi不同,所以要进行转换。