Java JTable Header calcHeaderWidth(int col)

Description

calcs the optimal header width of the given column

License

Open Source License

Declaration

public int calcHeaderWidth(int col) 

Method Source Code

//package com.java2s;
/*//from  w  ww.j  a  v a2 s  . c  om
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

import java.awt.Component;

import javax.swing.JTable;

import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;
import javax.swing.table.TableModel;

public class Main {
    private JTable jtable;

    /**
     * calcs the optimal header width of the given column
     */
    public int calcHeaderWidth(int col) {
        return calcHeaderWidth(getJTable(), col);
    }

    /**
     *  Calculates the optimal width for the header of the given table. The
     *  calculation is based on the preferred width of the header renderer.
     *
     *  @param table    the table to calculate the column width
     *  @param col      the column to calculate the widths
     *  @return         the width, -1 if error
     */
    public static int calcHeaderWidth(JTable table, int col) {
        if (table == null)
            return -1;

        if (col < 0 || col > table.getColumnCount()) {
            System.out.println("invalid col " + col);
            return -1;
        }

        JTableHeader header = table.getTableHeader();
        TableCellRenderer defaultHeaderRenderer = null;
        if (header != null)
            defaultHeaderRenderer = header.getDefaultRenderer();
        TableColumnModel columns = table.getColumnModel();
        TableModel data = table.getModel();
        TableColumn column = columns.getColumn(col);
        int width = -1;
        TableCellRenderer h = column.getHeaderRenderer();
        if (h == null)
            h = defaultHeaderRenderer;
        if (h != null) {
            // Not explicitly impossible
            Component c = h.getTableCellRendererComponent(table,
                    column.getHeaderValue(), false, false, -1, col);
            width = c.getPreferredSize().width + 5;
        }

        return width;
    }

    /**
     * returns the JTable
     */
    public JTable getJTable() {
        return jtable;
    }
}

Related

1. AddToTable(JTable tbl, Object[] obj, boolean head)
2. adjustHeader(JTable table)
3. calcHeaderWidth(JTable table, int col)
4. cleanHeaderCells(JTable table)
5. createTableHeaderEmptyColumnPainter(final JTable table)
6. getColumnHeaderWidth(TableColumn col, JTable table)