pdfcraft/crates/forms/README.md

printcraft-forms

Interactive forms (AcroForm, ISO 32000-2 §12.7). Layer L3; depends on printcraft-cos and printcraft-fonts.

API

let all: Vec<Field> = fields(&doc);                         // terminal fields with widgets, options, flags, /DA
set_value(&mut doc, "name", &FieldValue::Text("Ada".into()))?;
set_value(&mut doc, "agree", &FieldValue::Check(true))?;
set_value(&mut doc, "size", &FieldValue::Radio(Some("L".into())))?;
set_value(&mut doc, "toppings", &FieldValue::Choice(vec!["Ham".into()]))?;
reset(&mut doc, None)?;                                      // Clear form (back to /DV)

Behaviour

• Inheritable attributes (/FT, /Ff, /V, /DV, /DA, /Q, /MaxLen) are resolved down the field tree; the form's /DA and /Q are the last fallback.
• Text and choice fields get new appearance streams (/Tx BMC … EMC): auto-size (0 Tf), comb, multiline wrapping, password masking, quadding, /MK background and border, list-box selection. The /DA font is used when /DR has it as a simple font; otherwise Helvetica (WinAnsi).
• Check boxes and radio buttons switch /V and each widget's /AS. Widgets with no appearances get PrintCraft's own (a drawn check mark or dot; no symbol font needed).
• Values are validated (options, MaxLen, single vs multi-select, NoToggleToOff, read-only) and a failed call changes nothing.
• /RV (rich text) is removed when a value is set so it can't contradict /V.

Not yet

JavaScript actions (format, keystroke, validate, calculate; M6.4/M6.5), rich-text values, /MK /R rotation, field creation and properties (M6.6), FDF/XFDF import and export (M6.7).