Java JTable setting Column Width

Question

I have a JTable in which I set the column size as follows:

table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
table.getColumnModel().getColumn(0).setPreferredWidth(27);
table.getColumnModel().getColumn(1).setPreferredWidth(120);
table.getColumnModel().getColumn(2).setPreferredWidth(100);
table.getColumnModel().getColumn(3).setPreferredWidth(90);
table.getColumnModel().getColumn(4).setPreferredWidth(90);
table.getColumnModel().getColumn(6).setPreferredWidth(120);
table.getColumnModel().getColumn(7).setPreferredWidth(100);
table.getColumnModel().getColumn(8).setPreferredWidth(95);
table.getColumnModel().getColumn(9).setPreferredWidth(40);
table.getColumnModel().getColumn(10).setPreferredWidth(400);

This works fine, but when the table is maximized, I get empty space to the right of the last column. Is it possible to make the last column resize to the end of the window when resized?

I found AUTO_RESIZE_LAST_COLUMN property in docs but it does not work.

Edit: JTable is in a JScrollPane its prefered size is set.

Answer 1

fireTableStructureChanged();

will default the resize behavior ! If this method is called somewhere in your code AFTER you did set the column resize properties all your settings will be reset. This side effect can happen indirectly. F.e. as a consequence of the linked data model being changed in a way this method is called, after properties are set.

Answer 2

What happens if you call setMinWidth(400) on the last column instead of setPreferredWidth(400)?

In the JavaDoc for JTable, read the docs for doLayout() very carefully. Here are some choice bits:

When the method is called as a result of the resizing of an enclosing window, the resizingColumn is null. This means that resizing has taken place "outside" the JTable and the change - or "delta" - should be distributed to all of the columns regardless of this JTable's automatic resize mode.

This might be why AUTO_RESIZE_LAST_COLUMN didn't help you.

Note: When a JTable makes adjustments to the widths of the columns it respects their minimum and maximum values absolutely.

This says that you might want to set Min == Max for all but the last columns, then set Min = Preferred on the last column and either not set Max or set a very large value for Max.

Answer 3

Use this method

public static void setColumnWidths(JTable table, int... widths) {
    TableColumnModel columnModel = table.getColumnModel();
    for (int i = 0; i < widths.length; i++) {
        if (i < columnModel.getColumnCount()) {
            columnModel.getColumn(i).setMaxWidth(widths[i]);
        }
        else break;
    }

Or extend the JTable class:

public class Table extends JTable {
    public void setColumnWidths(int... widths) {
        for (int i = 0; i < widths.length; i++) {
            if (i < columnModel.getColumnCount()) {
                columnModel.getColumn(i).setMaxWidth(widths[i]);
            }
            else break;
        }
    }
}

And then

table.setColumnWidths(30, 150, 100, 100);

Answer 4

Use this code. It worked for me. I considered for 3 columns. Change the loop value for your code.

TableColumn column = null;
        for (int i = 0; i < 3; i++) {
            column = table.getColumnModel().getColumn(i);
            if (i == 0) 
                column.setMaxWidth(10);
            if (i == 2)
                column.setMaxWidth(50);
        }

Answer 5

With JTable.AUTO_RESIZE_OFF, the table will not change the size of any of the columns for you, so it will take your preferred setting. If it is your goal to have the columns default to your preferred size, except to have the last column fill the rest of the pane, You have the option of using the JTable.AUTO_RESIZE_LAST_COLUMN autoResizeMode, but it might be most effective when used with TableColumn.setMaxWidth() instead of TableColumn.setPreferredWidth() for all but the last column.

Once you are satisfied that AUTO_RESIZE_LAST_COLUMN does in fact work, you can experiment with a combination of TableColumn.setMaxWidth() and TableColumn.setMinWidth()

Answer 6

JTable.AUTO_RESIZE_LAST_COLUMN is defined as "During all resize operations, apply adjustments to the last column only" which means you have to set the autoresizemode at the end of your code, otherwise setPreferredWidth() won't affect anything!

So in your case this would be the correct way:

table.getColumnModel().getColumn(0).setPreferredWidth(27);
table.getColumnModel().getColumn(1).setPreferredWidth(120);
table.getColumnModel().getColumn(2).setPreferredWidth(100);
table.getColumnModel().getColumn(3).setPreferredWidth(90);
table.getColumnModel().getColumn(4).setPreferredWidth(90);
table.getColumnModel().getColumn(6).setPreferredWidth(120);
table.getColumnModel().getColumn(7).setPreferredWidth(100);
table.getColumnModel().getColumn(8).setPreferredWidth(95);
table.getColumnModel().getColumn(9).setPreferredWidth(40);
table.getColumnModel().getColumn(10).setPreferredWidth(400);
table.setAutoResizeMode(JTable.AUTO_RESIZE_LAST_COLUMN);