Thanks jbum.

It works for most keys but not for the backspace key which is odd. The backspace key does not backspace and still generates a square character. This is my code (I added your keycode test):

void keyPressed() {
    fullComment = splitTokens(captureText, ", ");
    if (key == CODED) {
     // ignore it.
   }
   else {
    userInputText = userInputText + key;  // add each character typed by the user to the end of the userInputText String variable.
    // If the return key is pressed, save the String and clear it
    if (key == RETURN || key == ENTER) {
      captureText = userInputText;
      appendStrings("userinput.txt", fullComment);
      userInputText = "";  // Clear the String by setting it equal to ""
    }
   }
  }
}  // end of TextField class

Actually, I just discovered this hidden message at the bottom of that page (ie. http://www.learningprocessing.com/examples/chapter-18/example-18-1/#comments ) which gives, in a few lines of code, a beautiful solution that works like magic. It is signed Mr. Winkle.


For those wondering about deleting mistyped letters instead of

typing = typing + key;

use this:

if (keyCode == BACKSPACE) {
typing = typing.substring(0, typing.length() - 1);
}
else
if (key != CODED) typing += key;

greets, mr.winkle