title: PDF Fields Appear Invisible with PDF Clown
body: <p>I use the Java version of <a href="http://www.stefanochizzolini.it/en/projects/clown/index.html" rel="nofollow">PDF Clown</a> to fill out the fields of PDF Acroforms. This works great and I'm able to programmatically fill out forms and save them without any issues.</p>
  
  <p>However, some PDF viewers render some of the text invisible in the fields I'm filling out, unless you click on them in which case they become visible. This <a href="http://acrobatusers.com/forum/forms-acrobat/inviisible-data-form-fields/index.php#comment-64711" rel="nofollow">forum post</a> explains that this can happen in form-fillable PDFs in general and that it can be fixed by setting the background color of the PDF field to "None", even if the GUI already says that the background color is "None." This has worked for others and I'd like to try it for myself.</p>
  
  <p>Unfortunately, I"m stuck on how to actually do this in PDFClown. There isn't a direct method like <code>field.setBackgroundColor(null)</code> for the Field class and I'm not able to figure out a way to do it by using one of the other accessor methods, like <code>getDefaultAppearanceState()</code>.</p>
  
  <p>Is there anyone who knows how to do this in PDF Clown?</p>
  
  <p>EDIT: A sample PDF with this issue can be found <a href="http://journeymangames.net/Doc%20Lightning%20Different.pdf" rel="nofollow">here</a>. Everything in this PDF was filled in with PDF Clown. Note in particular that the two fields in the upper left (labeled with "Name") are invisible until clicked on. The five fields in the right are also invisible until clicked on, except for the "Charisma" field, which was previously invisible, but then I manually typed in the value and then it was made visible. Everything else was put in by PDF Clown, but unlike the other fields was made visible.</p>
  
  <p>EDIT 2: It has since been discovered that this only happens when you overwrite values in an existing form-fillable character sheet. An original can be downloaded <a href="http://www.peginc.com/freebies/DL_Reloaded/DLEXCharacterSheet.pdf" rel="nofollow">here</a>.</p>