Last column in JTable detaches from edge of JScroll Pane

Question

i have a JTable in a JScrollPane which is in half of a JSplitPane.
The table has autoResizeMode set to AUTO_RESIZE_OFF to make the horizontal scrollbar appear.
However, when i resize the split pane to make the table bigger, the edge of the last column no longer runs to the edge of the JScrollPane, it detaches.
What i need is for the last column to be able to expand infinitely, but when the split pane size is being reduced, for the columns to disapear off the edge of the scroll pane and the scroll bar to appear. This is a mix of AUTO_RESIZE_OFF and AUTO_RESIZE_LAST_COLUMN.

Answer 1

I too had this problem. I had a method that would set the minimum size of columns based on the data within the table, etc. It seems that when you do anything to set the pref or min size of a column the horizontal scrolling gets all messed up. How I solved the problem is to basically swap the autosize method on the table back and forth whenever the parent component of the table is resized. Some example code follows.
First, add a inner class ComponentListener on the parent component the table is in (a frame in my case, I guess this could be the scroll pane too?):
_myFrame.addComponentListener( new ComponentAdapter()
    public void componentResized(ComponentEvent e)
        _parentResized();
});Now the _parentResized() method that is called by the inner class looks like this:
* Our parent container component was resized, so update how the table's
* columns are layed out.
private void _parentResized()
    TableColumnModel tcm = _table.getColumnModel();
    int colWidth = 0;
    for( int j = 0; j < tcm.getColumnCount(); j++ )
        colWidth += tcm.getColumn( j ).getPreferredWidth();
    // Have to check scroll for width > 0, because the first time this gets
    // called, it is 0, and that will cause the viewport to scale to fit the
    // entire table (which could be bad).  Note that this will get updated
    // if the window is resized as well.
    if( _tableScroll.getWidth() > 0 && colWidth < _tableScroll.getWidth() )
        _table.setAutoResizeMode( JTable.AUTO_RESIZE_ALL_COLUMNS );
    else
        _table.setAutoResizeMode( JTable.AUTO_RESIZE_OFF );
}What that does is whenever the table's parent component is resized it evaluates the pref width of the whole table, if it's greater than the scrollpane's width, it turns autosizing of columns off (which will make the horiz scrollbar work properly), if it is less than the scrollpane's width, it turns autosizing on. Hackish I know.
You need to make sure to call the _parentResized() method as well whenver you do something else that might cause the pref width of the table to be resized (like you repopulate and calc pref widths, etc.)
Hope this is of some use to you.