从PdfPTable列获取绝对宽度（iText）

Question

PdfPCell cell2;
PdfPTable table2 =  new PdfPTable(new float[]{(float) 4.5, (float) 0.5, 9});
table2.setWidthPercentage(100);

我尝试使用Table2.GetAbsoluteWidths()[2]，但结果是float0.0。

在PDF上动态计算表宽后，我想获得每个列的绝对宽度（已最大化）。

----------------编辑----------------------------------

String fullAlamatPP = "test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test test ";

float restrictions = (float) 330.12103; // this is width of a column from table

String alamatSesuaiKtpPP[] = restrictWidthOfFont(fullAlamatPP, font_body, restrictions);

Phrase p_alamat1_ct = new Phrase(alamatSesuaiKtpPP[0], font_body);
p_alamat1_ct.add(dottedline);
cell2 = new PdfPCell(p_alamat1_ct);
cell2.setBorder(PdfPCell.NO_BORDER);
table2.addCell(cell2);

Phrase p_alamat2_ct = new Phrase(alamatSesuaiKtpPP[1], font_body);
p_alamat2_ct.add(dottedline);
cell2 = new PdfPCell(p_alamat2_ct);
cell2.setBorder(PdfPCell.NO_BORDER);
table2.addCell(cell2);    

private static String[] restrictWidthOfFont(String character, Font font, float restrictions) {
        String results[];
        results = new String[] {"",""};
        String concatChar = " ";
        float widthOfString = 0;
        for (int i = 0; i < character.length();i++) {
            concatChar += character.charAt(i); 
            widthOfString = font.getCalculatedBaseFont(true).getWidthPoint(concatChar, font.getCalculatedSize());
//                System.out.println("widthOfString " + widthOfString);
            if (widthOfString > restrictions) {
                results[0] = concatChar.substring(0, concatChar.length() - 1);
                results[1] = character.substring(i, character.length());
                break;
            }
        }

        if (results[0] == "") {
            results[0] = character;
        }
        return results;
}    

是否可以在添加表文档之前获取列的宽度？

Answer 1

函数table.GetAbsoluteWidths()依赖于必须设置表的totalWidth的要求，因此table.GetTotalWidth()>0。

这是因为在com.itextpdf.text.pdf.pdfptable类内部调用了一个方法CalculateWidths()，然后该方法计算所有列的绝对宽度：

this.absoluteWidths[k] = this.totalWidth * this.relativeWidths[k] / total;

为了确保在检索relativeWidths数组之前设置了totalWidth,您需要：

• 或者(A)设置totalWidth（如本答案所述）
• 或(B)向表中添加单元格&将表添加到文档

下面的代码结合了您的算法，根据列的最大宽度限制，将文本（即长地址或alamat）拆分到单元格中：

import com.itextpdf.text.*;
import com.itextpdf.text.pdf.*;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Arrays;

public class TableWidthSample {

    public static void main(String[] args) {
        Document document = new Document();
        try {
            PdfWriter.getInstance(document, new FileOutputStream("TableColumnWidth.pdf"));
            document.open();

            PdfPTable table = createTableWithRelativeColumnWidths();

            // needed for calculation of getAbsoluteWidths: (A) totalWidth is set for table
            table.setTotalWidth(calculateTableWidthBasedOnPageA4(document, table));
            // now it prints width, because (A)
            printTableWidth(table, "after totalWidth set manually"); // absoluteWidths: [134.4857, 14.942857, 268.9714]

            // long text, that needs to be split among cells (fullAlamatPP)
            String text = "this is a very long text. The text contains a full address. Because the text is too long to be shown in the last cell, it is split.";
            // your CODE to fill text into cells based on restrictions
            addTextAcrossTableCells(table, text);

            document.add(table);

/*
            // need to add filled table to doc (B)
            addToDocumentCellsAndTable(document, table);
            // now it prints width, because (B)
            printTableWidth(table, "after added to doc"); // absoluteWidths: [134.4857, 14.942857, 268.9714]
*/
            document.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (DocumentException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private static PdfPTable createTableWithRelativeColumnWidths() {
        float[] relativeWidths = {4.5F, 0.5F, 9F};
        PdfPTable table = new PdfPTable(relativeWidths);
        table.setWidthPercentage(100F);
        printTableWidth(table, "after table created"); // absoluteWidths: [0.0, 0.0, 0.0]
        return table;
    }

    private static float calculateTableWidthBasedOnPageA4(Document document, PdfPTable table) {
        return (PageSize.A4.getWidth() - document.leftMargin() - document.rightMargin())
                * table.getWidthPercentage() / 100;
    }

    private static void addToDocumentCellsAndTable(Document document, PdfPTable table) throws DocumentException {
        // needed for calculation of getAbsoluteWidths: (B.1) add cells to table
        table.addCell("Hello");
        table.addCell("World");
        table.addCell("!");
        printTableWidth(table, "after cells added to table"); // absoluteWidths: [0.0, 0.0, 0.0]

        // needed for calculation of getAbsoluteWidths: (B.2) add table to doc
        document.add(table);
    }

    private static void addTextAcrossTableCells(PdfPTable table, String text) throws IOException, DocumentException {
        // restrictions; this is width of a column from table
        float maxColumnWidth = table.getAbsoluteWidths()[2]; // 330.12103F;
        System.out.println("use width of third column as max: " + maxColumnWidth);
        // sample font used for calculation of text-width
        Font font = new Font(BaseFont.createFont("Courier", BaseFont.CP1250, true), 12);

        // alamatSesuaiKtpPP
        String splitText[] = getTextPartsUsingFontWithMaxWidth(text, font, maxColumnWidth);
        String dottedLine = "..";
        table.addCell("Alamat / Address:");

        // p_alamat1_ct
        Phrase phrase1 = new Phrase(splitText[0], font);
        phrase1.add(dottedLine);
        PdfPCell cell1 = new PdfPCell(phrase1);
        cell1.setBackgroundColor(BaseColor.LIGHT_GRAY);
        cell1.setBorder(PdfPCell.NO_BORDER);
        table.addCell(cell1);

        // p_alamat2_ct
        Phrase phrase2 = new Phrase(splitText[1], font);
        phrase2.add(dottedLine);
        PdfPCell cell2 = new PdfPCell(phrase2);
        cell2.setBorder(PdfPCell.NO_BORDER);
        table.addCell(cell2);
    }

    private static String[] getTextPartsUsingFontWithMaxWidth(String text, Font font, float maxWidth) {
        String results[] = new String[] {"",""};
        String firstPartOfText = " ";
        float widthOfText = 0;
        for (int i = 0; i < text.length();i++) {
            firstPartOfText += text.charAt(i);
            widthOfText = font.getCalculatedBaseFont(true).getWidthPoint(firstPartOfText, font.getCalculatedSize());
            System.out.printf("%d: widthOfText: %f\n", i, widthOfText);
            if (widthOfText > maxWidth) {
                results[0] = firstPartOfText.substring(0, firstPartOfText.length() - 1);
                results[1] = text.substring(i); // second argument "text.length()" is not needed
                break;
            }
        }

        if (results[0] == "") {
            results[0] = text;
        }
        return results;
    }

    private static void printTableWidth(PdfPTable table, String labelText) {
        float[] absoluteWidths = table.getAbsoluteWidths();
        System.out.println(labelText + "> getAbsoluteWidths: " + Arrays.toString(absoluteWidths));
    }
}