print the full content of JScrollpane

Hi,

I want to print JPanel (print, export to PDF, etc.) which is inside jScrollpane. JPanel is kinda large.
I need to scale it to fit A4 width and then print it (probably many pages will be needed).

I tried to use iText to export to Pdf, but it exports only the first page.

I tried to overwrite print method for JFrame(which contains JScrollpane), smth like

public int print(Graphics g, PageFormat pageFormat,
int pageIndex) throws PrinterException {
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.black);
int fontHeight=g2.getFontMetrics().getHeight();
int fontDesent=g2.getFontMetrics().getDescent();

...
double pageWidth =
pageFormat.getImageableWidth();
double rectWidth = (double) drawRect.getWidth();
...

double scale = 1;
if (rectWidth >= pageWidth) {
scale = pageWidth / rectWidth;
logger.debug("scale " + scale);
}

double rectHeight = drawRect.getHeight()*scale;
...

double rectHeightPage = pageFormat.getImageableHeight() - 25;
...

int totalNumPages=
(int)Math.ceil((
(double)rectHeight/rectHeightPage));
logger.debug("totalNumPages " + totalNumPages);

if(pageIndex>=totalNumPages) {
return NO_SUCH_PAGE;
}

g2.translate(pageFormat.getImageableX(),
pageFormat.getImageableY());


if (pageIndex + 1 == totalNumPages) {


...
}
//else clip to the entire area available.
else{



g2.setClip(0,
(int)(rectHeightPage*pageIndex),
(int) Math.ceil(rectWidth),
(int) Math.ceil(
rectHeightPage
));
...


}

g2.scale(scale,scale);
drawRect.paint(g2);
g2.scale(1/scale,1/scale);


return Printable.PAGE_EXISTS;
}



Scaling works, but again - it prints only the first page, and the rest of pages are empty.

What shall I do? Please help.

Can you advance the contents of the JScrollPane as each new page is requested to be printed? What is the value of pageIndex?
I haven't worked with printing in a while.

pageIndex values are from 0 till totalNumPages.
setClip selects the right area (according to logger - Set clip x: 0; y: 2450; width:1165; height: 817, etc. - it changes the y coordinate as it should do).
But anyway other pages are empty ;(


And I am a total newbie, working with Swing for the first time actually....

OK, I found a mistake.

g2.translate(pageFormat.getImageableX(), pageFormat.getImageableY());

I changed to g2.translate(pageFormat.getImageableX(), -rectHeightPage*pageIndex); and it works.

But it separates pages by pixels (meaning if I have some text on the picture, the letters are split across pages).

Any ideas how to solve it?

Quote:

---

the letters are split across pages). Any ideas how to solve it?

---

Scan the image and set the page length to be before the letters that are split.

And how to do the scanning?

P.S. Images can be of different size; multiple textareas on them can be of different size and on different positions.

Where do you want the page break to be?
Do you know how many pixels fit on a page vertically?
Start at that y location and move up until you find a horizontal row of pixels that do not have and thing that you don't want to split across pages. Like a row of white pixels.

There can be vertical lines and the background color is set.
But I do not want to make breaks on text, horizontal lines or any other graphics.

And since I am a total newbie, I do not know how to scan JPanel Graphics to get pixel array or smth and how to get to know if there is text/smth.

When you build the page layout, can you determine where the components are being placed?
If you can, then make sure they are not crossing a page boundary.

It is generated dynamically...
Meaning I check the y coordinate of the last drawn object;
and then smth like
lastY = lastY + newObject.getHeight + someExtraSpace.

So, I can't know the coordinates of objects on the Graphics (objects - polygons, lines, texts - everything of different size).

And btw pageLayout is null (otherwise I couldn't position textAreas properly).

If you are positioning the components (layout = null) then you should have 100% control over where the component is positioned.

Well, the positioning is kinda relative - according to other objects positions....

Yes, of course. Your problem is to keep components from spanning a page break.
Since you have 100% control of where you put each component and you know where the page break is, you should be able to detect if a component will span the break.