..
> I want to create a swing component (from JComponent ) which can have
>a fixed size which I specify (default to 700,300).
setPreferredSize(), then..
>..I want it to have
>same size when I put it in a layout.
..put in a layout and position in the layout that
honours the preferred size..
>..and when I set a new size for it
>I want it to set itself to the new size, and make itself fully
>visible.
..then pack() the root window.
> How to make that work ?
See above, and probably also the Swing and layouts
sections of the 'Java Tutorial'.
HTH

Signature
Andrew Thompson
http://www.athompson.info/andrew/