Anubis Anubis - 2 months ago 21
Java Question

Auto resizing the JTable column widths

I need my JTable to automatically re-size its column widths to fit the content. I found the

class very useful. But there's a small problem. Say i have 5 columns, and their content is very short. In that case, if i use the auto adjuster, it sets the first four columns widths according to their content and gives all the rest of space to the last column. Please see the example.

enter image description here

Here the last column,
Balance
is given all the excess space. But what if i need to give that space to one of the middle columns. In the above case, i need to assign that space to the third column,
name
. I tried modifying the
TableColumnAdjuster
class's
adjustColumns()
method. But I couldn't get it working.

I tried both
column.setPreferredWidth()
and
column.setWidth()
for changing column sizes. But seems it doesn't change anything. How can I effectively change the column sizes of a
JTable
. If there's some other alternative or a direct answer to my main problem, that's better. Thanks!

Answer

You can try the next:

public void resizeColumnWidth(JTable table) {
    final TableColumnModel columnModel = table.getColumnModel();
    for (int column = 0; column < table.getColumnCount(); column++) {
        int width = 15; // Min width
        for (int row = 0; row < table.getRowCount(); row++) {
            TableCellRenderer renderer = table.getCellRenderer(row, column);
            Component comp = table.prepareRenderer(renderer, row, column);
            width = Math.max(comp.getPreferredSize().width +1 , width);
        }
        if(width > 300)
            width=300;
        columnModel.getColumn(column).setPreferredWidth(width);
    }
}

JTable

This needs to be executed before the resize method.
If you have:

table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);

JTable