How to make JTable both AutoResize and horizontall scrollable?

Question

I am putting a JTable into a JScrollPane

But When I set JTable Auto Resizeable, then it won't have horizontal scroll bar.

if I set AUTO_RESIZE_OFF, then the Jtable won't fill the width of its container when the column width is not big enough.

So how can I do this:

1. when the table is not wide enough, expand to fill its container width
2. when the table is wide enough, make it scrollable.

Thanks

Answer 1

You need to customize the behaviour of the Scrollable interface.

import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.table.*;  public class TableHorizontal extends JFrame {     public TableHorizontal()     {         final JTable table = new JTable(10, 5)         {             public boolean getScrollableTracksViewportWidth()             {                 return getPreferredSize().width < getParent().getWidth();             }         };         table.setAutoResizeMode( JTable.AUTO_RESIZE_OFF );         final JScrollPane scrollPane = new JScrollPane( table );         getContentPane().add( scrollPane );     }      public static void main(String[] args)     {         TableHorizontal frame = new TableHorizontal();         frame.setDefaultCloseOperation( EXIT_ON_CLOSE );         frame.pack();         frame.setSize(400, 300);         frame.setVisible(true);     } } 

The above code basically sizes the component at its preferred size or the viewport size, whichever is greater.

Answer 2

If for some reason customising JTable is not an option (e.g. it might be created in third-party code), you can achieve the same result by setting it to toggle between two different JTable AUTO_RESIZE modes whenever the containing viewport is resized, e.g.:

jTable.getParent().addComponentListener(new ComponentAdapter() {     @Override     public void componentResized(final ComponentEvent e) {         if (jTable.getPreferredSize().width < jTable.getParent().getWidth()) {             jTable.setAutoResizeMode(JTable.AUTO_RESIZE_ALL_COLUMNS);         } else {             jTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);         }     } });