java - Canvas 错误地绘制表 itext7 中的高度单元格

Question

我绘制表格如下:Draw custom borders for table with more flexibility in itext7

但是我但是对于大数据，表格中的高度单元格绘制得很糟糕。

 PdfDocument pdfDoc = new PdfDocument(new PdfWriter("_testPd/dashed_underline.pdf"));
        Document doc = new Document(pdfDoc, PageSize.A5);

        Table table = new Table(3).useAllAvailableWidth().setFixedLayout();
        table.addCell("Highway System that runs east from the Indiana state line near Lake Michigan through the southern Lower Peninsula to Detroit, then n");
        table.addCell("Highway System that runs east from the Indiana state line near Lake Michigan through the southern Lower Peninsula to Detroit, then n");
        table.addCell("Highway System that runs east from the Indiana state line near Lake Michigan through the southern Lower Peninsula to Detroit, then n");

        table.addCell("Pell morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. Praesent dapibus, neque id cursus faucibus, tortor neque egestas augue, eu vulputate magna eros eu erat. Aliquam erat volutpat. Nam dui mi, tincidunt quis, accumsan porttitor, facilisis luctus, metus");



        table.setNextRenderer(new CustomTableRenderer(table));


        doc.add(table);

        doc.close();

还有一个例子:

  Table table = new Table(3);
    table.addCell("hello1 ");
    table.addCell("hello2 ");
    table.addCell("hello3 ");
    table.addCell("hello4\nWord ");
    table.addCell("hello5 ");

Answer 1

您的自定义渲染器中存在一个小错误:heights列表中的项目表示从最高到最低的行，但您是从最低到最高绘制边框。

应使用以下代码来绘制水平线:

        // Draw horizontal lines
        float curY = getOccupiedAreaBBox().getTop();
        for (int i = 0; i <= heights.size(); i++) {
            canvas.moveTo(getOccupiedAreaBBox().getLeft() - 3, curY);
            canvas.lineTo(getOccupiedAreaBBox().getRight() + 3, curY + r.nextInt(4));
            if (i < heights.size()) {
                float curHeight = heights.get(i);
                curY -= curHeight;
            }
        }