🚀 go-pugleaf

On Thu, 05 Aug 1999 14:56:37 -0600, David <david.v.clark@lmco.com>
wrote:

>Good day -
>
>Using JBuilder 3 -
>
>I have several JTextFields that the user types into.  I would like to
>restrict the number of characters to 10 (for example).  Has anyone done
>this?  I thought perhaps DocumentListener was the solution, but couldn't
>get it to work.
>
>I would greatly appreciate any help you can offer.
>
>David
>

We've already written an extended class to JTextField which does this
for you (this, unfortunately, is company property and I can't hand it
out). However, we still have a bug to solve.

There are two possibilities: the first is to indeed catch the key
events as described in the other reply to your question, the second is
to create a new class JTextFieldRestricted.

In the latter solution, the new class overrides the
"createDefaultModel" method of JTextField and returns a special
"PlainDocumentRestricted" object. 
PlainDocumentRestricted overrides insterString of PlainDocument to
restrict the input. This has the advantage of also supporting
copy&paste.