bustos 2005-05-22

If a horizontal JSplitPane has a tall component on the left and a short, non-scroll-
savvy component in a JScrollPane on the right, with scrollbar policies set to
_AS_NEEDED, then the JSplitPane will lay the left component out at its minimum width
instead of at its preferred width.

The attached ScrollPaneBug.java demonstrates this.

  xxxxx@xxxxx   2005-05-22 23:37:59 GMT
ScrollPaneLayout sometimes improperly calculates preferred layout size. A case is described above.
Posted Date : 2007-06-28 16:10:40.0

There is no any workaround.

Not a regression in 5.0. Reproducible in 1.4.0.
  xxxxx@xxxxx   2005-07-21 19:30:37 GMT
Posted Date : 2005-07-21 19:30:37.0

The cause is perfectly described in the comments section (thanks to   xxxxx@xxxxx  ).
Briefly the cause is in the javax.swing.ScrollPaneLayout:preferredLayoutSize() method.
Look at the following code:
...
492    if (viewport !=  null) {
493        extentSize = viewport.getPreferredSize();
494        viewSize = viewport.getViewSize();
495        view = viewport.getView();
496    }
...

For the preferred viewSize calculation the viewport.getViewSize() method is used. However the method can return not only preferred size. If the view size has been set, getViewSize() returns the view size, not the preferred size. It is the cause.

To overcome the problem the view.getPreferredSize() method should be used instead of the viewport.getViewSize() to obtain the view preferred size.
Posted Date : 2007-06-28 16:10:41.0