Swing Hacks

Add Column Selection to JTables #22

Chapter 3, Tables and Trees

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HACK

When you run this version of ColumnResizer, the table should look like

Figure 3-3.

Having done this, it’s still possible to crush either table cells or headers if

you resize (programatically or by dragging the frame’s corner) to a point

where there’s just not enough room for all the content. If you really wanted

to keep header cells intact, you could alter the previous code to set the

TableColumn’s minimum width to the preferred width of the header cell,

assuming the header isn’t much wider than the content. Ultimately, it’s

really a question of what data you’re putting in the table and what looks

right to you.

Hacking the Hack

“But,” you might be saying, “what if I don’t have my table data in advance?”

If you have some idea of what the data is probably going to be like, you

could create your table, add this “prototype” data as a row, size the col-

umns, and then remove the prototype…all before ever making the table visi-

ble. That would give your users reasonable default sizing, and then they

could resize columns by dragging header borders as desired. Of course, you

could always hook up a

TableModelListener and resize the columns every

time data is inserted, deleted, or updated, but having the column widths

jump around magically can be very annoying.

H A C K

#22

Add Column Selection to JTables Hack #22

So, why can’t I select a column ...