Fix previous fix to setting checkbox value (fixes #1056)

The code accepted values other than /Yes but still used /Yes as the
checked value instead of obeying the normal appearance dictionary.

1 files changed, 3 insertions, 1 deletions

diff --git a/include/qpdf/QPDFFormFieldObjectHelper.hh b/include/qpdf/QPDFFormFieldObjectHelper.hh
index f31bb7bd..881a7db4 100644
--- a/include/qpdf/QPDFFormFieldObjectHelper.hh
+++ b/include/qpdf/QPDFFormFieldObjectHelper.hh
@@ -166,7 +166,9 @@ class QPDFFormFieldObjectHelper: public QPDFObjectHelper
     // either /Tx (text) or /Ch (choice), set /NeedAppearances to true. You can explicitly tell this
     // method not to set /NeedAppearances if you are going to generate an appearance stream
     // yourself. Starting with qpdf 8.3.0, this method handles fields of type /Btn (checkboxes,
-    // radio buttons, pushbuttons) specially.
+    // radio buttons, pushbuttons) specially. When setting a checkbox value, any value other than
+    // /Off will be treated as on, and the actual value set will be based on the appearance stream's
+    // /N dictionary, so the value that ends up in /V may not exactly match the value you pass in.
     QPDF_DLL
     void setV(QPDFObjectHandle value, bool need_appearances = true);