Question

我正在尝试打印带有一些绘制图形的JPanel（覆盖paintComponent）。图形太大，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：

选择pageFormat / Paper类型

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

当我在我的JPanel类中编写print（）方法（实现Printable）时，我似乎无法掌握边距？我使用graphics.translate(pageFormat.getImageableX(), pageFormat.getImageableY());使它开始绘制在正确的topleft角（0; 0）并且考虑边距（即，从（80; 100）开始更多）。但它打印在底部和右边距上，我不希望它做，因为这会否定用户的意愿。

这是我的print（）方法的代码作为参考，当你不让用户设置纸张时（使用默认设置），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;
        }
   }

Answer 1

在发布此问题并回到我的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();

使用

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

getImageableWidth()返回totalPaperWidth-totalMargins，而getWidth()只返回totalPaperWidth。这使得print（）方法不会在每个页面上绘制得更多！

使用java打印时如何获得Paper的边距？

1 个答案: