Allow setting a form field's value

2 files changed, 40 insertions, 0 deletions

diff --git a/include/qpdf/QPDFAcroFormDocumentHelper.hh b/include/qpdf/QPDFAcroFormDocumentHelper.hh
index d786fff4..2aa0d377 100644
--- a/include/qpdf/QPDFAcroFormDocumentHelper.hh
+++ b/include/qpdf/QPDFAcroFormDocumentHelper.hh
@@ -135,6 +135,23 @@ class QPDFAcroFormDocumentHelper: public QPDFDocumentHelper
     QPDFFormFieldObjectHelper
     getFieldForAnnotation(QPDFAnnotationObjectHelper);
 
+    // Return the current value of /NeedAppearances. If
+    // /NeedAppearances is missing, return false as that is how PDF
+    // viewers are supposed to interpret it.
+    QPDF_DLL
+    bool getNeedAppearances();
+
+    // Indicate whether appearance streams must be regenerated. If you
+    // modify a field value, you should call setNeedAppearances(true)
+    // unless you also generate an appearance stream for the
+    // corresponding annotation at the same time. If you generate
+    // appearance streams for all fields, you can call
+    // setNeedAppearances(false). If you use
+    // QPDFFormFieldObjectHelper::setV, it will automatically call
+    // this method unless you tell it not to.
+    QPDF_DLL
+    void setNeedAppearances(bool);
+
   private:
     void analyze();
     void traverseField(QPDFObjectHandle field,
diff --git a/include/qpdf/QPDFFormFieldObjectHelper.hh b/include/qpdf/QPDFFormFieldObjectHelper.hh
index b45955a3..c22703aa 100644
--- a/include/qpdf/QPDFFormFieldObjectHelper.hh
+++ b/include/qpdf/QPDFFormFieldObjectHelper.hh
@@ -114,6 +114,29 @@ class QPDFFormFieldObjectHelper: public QPDFObjectHelper
     QPDF_DLL
     int getQuadding();
 
+    // Set an attribute to the given value
+    QPDF_DLL
+    void setFieldAttribute(std::string const& key, QPDFObjectHandle value);
+
+    // Set an attribute to the given value as a Unicode string (UTF-16
+    // BE encoded). The input string should be UTF-8 encoded.
+    QPDF_DLL
+    void setFieldAttribute(std::string const& key,
+                           std::string const& utf8_value);
+
+    // Set /V (field value) to the given value. Optionally set
+    // /NeedAppearances to true. You can explicitly tell this method
+    // not to set /NeedAppearances if you are going to explicitly
+    // generate an appearance stream yourself.
+    QPDF_DLL
+    void setV(QPDFObjectHandle value, bool need_appearances = true);
+
+    // Set /V (field value) to the given string value encoded as a
+    // Unicode string. The input value should be UTF-8 encoded. See
+    // comments above about /NeedAppearances.
+    QPDF_DLL
+    void setV(std::string const& utf8_value, bool need_appearances = true);
+
   private:
     class Members
     {