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我正在尝试打印一个带有一些绘制图形的JPanel（覆盖paintComponent）。图形是如此之大，以至于它们不适合单个页面，因此我让它跨越多个页面。我的问题在于，如果我让用户通过调用来选择 pageFormat/Paper 类型：

PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
PageFormat pf = printJob.pageDialog(aset);
printJob.setPrintable(canvas, pf);

当我在 JPanel 类中编写 print() 方法（实现 Printable）时，我似乎无法控制边距？我graphics.translate(pageFormat.getImageableX(), pageFormat.getImageableY());用来让它在正确的左上角 (0;0) 开始绘制，并考虑到边距（即，从 (80; 100) 左右开始更多）。但随后它会打印在底部和右边距上，我不希望它这样做，因为这否定了用户的意愿。

这是我的 print() 方法的代码作为参考，当您不让用户设置纸张时（使用默认值代替），它可以正常工作：

    Rectangle[] pageBreaks;

    public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
        //Calculate how many pages our print will be
        if(pageBreaks == null){
            double pageWidth = pageFormat.getPaper().getWidth();
            double pageHeight = pageFormat.getPaper().getHeight();

            //Find out how many pages we need
            int numberOfPagesHigh = (int) Math.ceil(size.getHeight()/pageHeight);
            int numberOfPagesWide = (int) Math.ceil(size.getWidth()/pageWidth); 
            pageBreaks = new Rectangle[numberOfPagesHigh*numberOfPagesWide];

            double x = 0;
            double y = 0;
            int curXPage = 0;

            //Calculate what we will print on each page
            for (int i = 0; i < pageBreaks.length; i++){
                double xStart = x;
                double yStart = y;
                x += pageWidth;

                pageBreaks[i] = new Rectangle((int)xStart, (int)yStart, (int)pageWidth, (int)pageHeight);

                curXPage++;
                if (curXPage > numberOfPagesWide){
                    curXPage = 0;
                    x = 0;
                    y += pageHeight;
                }
            }


        }

        if (pageIndex < pageBreaks.length){
            //Cast graphics to Graphics2D for richer API
            Graphics2D g2d = (Graphics2D) graphics;

            //Translate into position of the paper
            g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());

            //Setup our current page
            Rectangle rect = pageBreaks[pageIndex];

            g2d.translate(-rect.x, -rect.y);
            g2d.setClip(rect.x, rect.y, rect.width, rect.height);

            //Paint the component on the graphics object
            Color oldBG = this.getBackground();
            this.setBackground(Color.white);
            util.PrintUtilities.disableDoubleBuffering(this);
            this.paintComponent(g2d);
            util.PrintUtilities.enableDoubleBuffering(this);
            this.setBackground(oldBG);

            //Return
            return PAGE_EXISTS;
        }
        else {
            return NO_SUCH_PAGE;
        }
   }
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1 回答 1

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在发布这个问题并返回到我的 IDE 后，我很容易找到答案。而不是使用

double pageWidth = pageFormat.getPaper().getWidth();
double pageHeight = pageFormat.getPaper().getHeight();

采用

double pageWidth = pageFormat.getImageableWidth();
double pageHeight = pageFormat.getImageableHeight();

getImageableWidth()返回totalPaperWidth-totalMargins，而只getWidth()返回totalPaperWidth。这使得 print() 方法不会在每一页上绘制更多内容！

于 2010-04-12T12:52:41.603 回答