Set Maximum Width of JEditorPane

Name: sv35042 Date: 10/18/2002


FULL PRODUCT VERSION :
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92)
Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode)


I've seen this on Linux Solaris and Windows, though not
always 100% consistently.

A DESCRIPTION OF THE PROBLEM :
There is no way to set the maximum width of a JEditorPane
without setting the height as well. If you use
setMaximumSize() with a large value for the height, some
layout managers just ignore it (especially GridBagLayout) so
you end up having to force everything through
setPreferredSize() but then there's no (easy) way to
persuade the component to behave as though it has a maximum
width and a preferred height that is dependent on the
content (which is effectively outside my control.)

There isn't a (directly) containing JViewport because there
are really several components (including several of these
JEditorPanes) which are being scrolled as a piece.

It would be *extremely* nice if it was possible to just
directly specify the constraint in the one dimension and
have the component work out what its natural size in the
other should be, and I have trouble imagining that I am the
only person who wants this feature.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
  To reproduce this, create a JEditorPane (or JTextPane) and
put it inside a JPanel (using a GridBagLayout.) Then use
the JEditorPane's setContentType() to select "text/html" and
setText() method to put some content with a long-ish
paragraph in.

EXPECTED VERSUS ACTUAL BEHAVIOR :
What I'd like is to be able to control the width of the
window, given that HTML is a series of paragraphs which can
be line-broken between words, but what I get by default is a
huge single line. Forcing people to scroll horizontally is
not a good move in UI terms.

REPRODUCIBILITY :
This bug can be reproduced often.

CUSTOMER WORKAROUND :
final int MAXWIDTH = 500;
JTextPane htmlPane = new JTextPane() {
   private Rectangle rect(javax.swing.text.Position p)
      throws javax.swing.text.BadLocationException
   {
      int off = p.getOffset();
      Rectangle r = modelToView(off>0 ? off-1 : off);
      return r;
   }
   public Dimension getPreferredSize() {
      try {
         Rectangle start =
            rect(getDocument().getStartPosition());
         Rectangle end =
            rect(getDocument().getEndPosition());
         if (start==null || end==null) {
            return super.getPreferredSize();
         }
         int height = end.y + end.height - start.y + 4;
         return new Dimension(MAXWIDTH, height);
      } catch (javax.swing.text.BadLocationException e) {
         return super.getPreferredSize();
      }
   }
};
htmlPane.setPreferredSize(new Dimension(MAXWIDTH,32767));
panel.horizExpand();
panel.add(htmlPane);
panel.doLayout();
htmlPane.setPreferredSize(null);
(Review ID: 158357)
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