arrowbutton.java

这个项目是为Java平台提供一个灵活的日历组件(Ok)

/*
 *  NachoCalendar
 *
 * Project Info:  http://nachocalendar.sf.net
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by the
 * Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * Changes
 * -------
 *
 * ArrowButton.java
 *
 * Created on August 13, 2004, 11:44 AM
 */

package net.sf.nachocalendar.components;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;

import javax.swing.JButton;

/** JButton showing an arrow.
 * @author Ignacio Merani
 */
public class ArrowButton extends JButton {
    /** Default size. */
    private int defaultsize = 16;

    /** Direction for the arrow. */
    private int direction;

    /** Creates a new instance of ArrowButton.
     * @param direction direction of the arrow
     */
    public ArrowButton(int direction) {
        super();
        this.direction = direction;
    }
    
    /** 
     * Invoked by Swing to draw components.
     * Applications should not invoke <code>paint</code> directly,
     * but should instead use the <code>repaint</code> method to
     * schedule the component for redrawing.
     * <p>
     * This method actually delegates the work of painting to three
     * protected methods: <code>paintComponent</code>,
     * <code>paintBorder</code>,
     * and <code>paintChildren</code>.  They're called in the order
     * listed to ensure that children appear on top of component itself.
     * Generally speaking, the component and its children should not
     * paint in the insets area allocated to the border. Subclasses can
     * just override this method, as always.  A subclass that just
     * wants to specialize the UI (look and feel) delegate's
     * <code>paint</code> method should just override
     * <code>paintComponent</code>.
     *
     * @param g  the <code>Graphics</code> context in which to paint
     */
    public void paint(Graphics g) {
        super.paint(g);
        int mid, i, j, x, y;
        int w, h, size;
        
        w = getSize().width;
        h = getSize().height;
        size = Math.min((h - 4) / 3, (w - 4) / 3);
        size = Math.max(size, 2);
        x = (w - size) / 2;
        y = (h - size) / 2;
        j = 0;
        size = Math.max(size, 2);
        mid = (size / 2) - 1;
        
        g.translate(x, y);
        if (isEnabled()) {
            g.setColor(getForeground());
        } else g.setColor(Color.gray);
        
        switch (direction) {
            case NORTH:
                for (i = 0; i < size; i++) {
                    g.drawLine(mid - i, i, mid + i, i);
                }
                break;
            case SOUTH:
                j = 0;
                for (i = size - 1; i >= 0; i--) {
                    g.drawLine(mid - i, j, mid + i, j);
                    j++;
                }
                break;
            case WEST:
                for (i = 0; i < size; i++) {
                    g.drawLine(i, mid - i, i, mid + i);
                }
                break;
            case EAST:
                j = 0;
                for (i = size - 1; i >= 0; i--) {
                    g.drawLine(j, mid - i, j, mid + i);
                    j++;
                }
                break;
            default:
                
        }
    }
    
    /** 
     * If the <code>preferredSize</code> has been set to a
     * non-<code>null</code> value just returns it.
     * If the UI delegate's <code>getPreferredSize</code>
     * method returns a non <code>null</code> value then return that;
     * otherwise defer to the component's layout manager.
     *
     * @return the value of the <code>preferredSize</code> property
     */
    public Dimension getPreferredSize() {
        return new Dimension(defaultsize, defaultsize);
    }
    
    /** 
     * Getter for property direction.
     * @return Value of property direction.
     */
    public int getDirection() {
        return this.direction;
    }
    
    /** 
     * Setter for property direction.
     * @param direction New value of property direction.
     */
    public void setDirection(int direction) {
        this.direction = direction;
    }
    
}