[PDFBOX-4594] Multiline field text with auto font sizing should be size adjusted

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.16
• Fix Version/s: 2.0.21, 3.0.0 PDFBox
• Component/s: AcroForm
• External issue URL: https://stackoverflow.com/questions/56938135/pdfbox-inconsistent-pdtextfield-autosize-behavior-after-setvalue
• Assignee: Maruan Sahyoun
• Reporter: Tilman Hausherr
• Created: 10/Jul/19 17:21
• Updated: 21/Aug/20 04:55
• Resolved: 24/Jun/20 10:05

Description

The code to set the size of multiline sets it to 12 when the font size is 0 in /DA. However Adobe does this differently. Attached: file generated by the code below, and file after adding a "d" in the field with Adobe Reader.

The code to generate the file:

try (PDDocument document = new PDDocument())
{
    PDPage page = new PDPage(PDRectangle.A4);
    document.addPage(page);

    // Adobe Acrobat uses Helvetica as a default font and
    // stores that under the name '/Helv' in the resources dictionary
    PDFont font = PDType1Font.HELVETICA;
    PDResources resources = new PDResources();
    resources.put(COSName.getPDFName("Helv"), font);

    // Add a new AcroForm and add that to the document
    PDAcroForm acroForm = new PDAcroForm(document);
    document.getDocumentCatalog().setAcroForm(acroForm);

    // Add and set the resources and default appearance at the form level
    acroForm.setDefaultResources(resources);

    // Acrobat sets the font size on the form level to be
    // auto sized as default. This is done by setting the font size to '0'
    String defaultAppearanceString = "/Helv 0 Tf 0 g";
    acroForm.setDefaultAppearance(defaultAppearanceString);

    // Add a form field to the form.
    PDTextField textBox = new PDTextField(acroForm);
    textBox.setPartialName("SampleField");

    // Acrobat sets the font size to 12 as default
    // This is done by setting the font size to '12' on the
    // field level.
    // The text color is set to blue in this example.
    // To use black, replace "0 0 1 rg" with "0 0 0 rg" or "0 g".
    defaultAppearanceString = "/Helv 0 Tf 0 0 1 rg";
    textBox.setDefaultAppearance(defaultAppearanceString);
    textBox.setMultiline(true);

    // add the field to the acroform
    acroForm.getFields().add(textBox);

    // Specify the widget annotation associated with the field
    PDAnnotationWidget widget = textBox.getWidgets().get(0);
    PDRectangle rect = new PDRectangle(50, 750, 200, 15);
    widget.setRectangle(rect);
    widget.setPage(page);

    // set green border and yellow background
    // if you prefer defaults, just delete this code block
    PDAppearanceCharacteristicsDictionary fieldAppearance
            = new PDAppearanceCharacteristicsDictionary(new COSDictionary());
    fieldAppearance.setBorderColour(new PDColor(new float[]{0,1,0}, PDDeviceRGB.INSTANCE));
    fieldAppearance.setBackground(new PDColor(new float[]{1,1,0}, PDDeviceRGB.INSTANCE));
    widget.setAppearanceCharacteristics(fieldAppearance);

    // make sure the widget annotation is visible on screen and paper
    widget.setPrinted(true);

    // Add the widget annotation to the page
    page.getAnnotations().add(widget);

    // set the field value
    textBox.setValue("Sample field");

    document.save("target/SimpleMultilineForm.pdf");
}

Issue Links

• relates to: PDFBOX-4568 Field text poorly vertically aligned