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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package javax.swing.plaf.metal;

import java.awt.*;
import java.awt.event.*;
import javax.swing.plaf.basic.*;
import javax.swing.*;
import javax.swing.plaf.*;
import javax.swing.border.*;
import java.io.Serializable;


JButton subclass to help out MetalComboBoxUI


Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeansTM
has been added to the java.beans package. Please see XMLEncoder. 
Author:Tom Santos
See Also:
/**
 * JButton subclass to help out MetalComboBoxUI
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans<sup><font size="-2">TM</font></sup>
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @see MetalComboBoxButton
 * @author Tom Santos
 */
public class MetalComboBoxButton extends JButton {
    protected JComboBox comboBox;
    protected JList listBox;
    protected CellRendererPane rendererPane;
    protected Icon comboIcon;
    protected boolean iconOnly = false;

    public final JComboBox getComboBox() { return comboBox;}
    public final void setComboBox( JComboBox cb ) { comboBox = cb;}

    public final Icon getComboIcon() { return comboIcon;}
    public final void setComboIcon( Icon i ) { comboIcon = i;}

    public final boolean isIconOnly() { return iconOnly;}
    public final void setIconOnly( boolean isIconOnly ) { iconOnly = isIconOnly;}

    MetalComboBoxButton() {
        super( "" );
        DefaultButtonModel model = new DefaultButtonModel() {
            public void setArmed( boolean armed ) {
                super.setArmed( isPressed() ? true : armed );
            }
        };
        setModel( model );
    }

    public MetalComboBoxButton( JComboBox cb, Icon i,
                                CellRendererPane pane, JList list ) {
        this();
        comboBox = cb;
        comboIcon = i;
        rendererPane = pane;
        listBox = list;
        setEnabled( comboBox.isEnabled() );
    }

    public MetalComboBoxButton( JComboBox cb, Icon i, boolean onlyIcon,
                                CellRendererPane pane, JList list ) {
        this( cb, i, pane, list );
        iconOnly = onlyIcon;
    }

    public boolean isFocusTraversable() {
        return false;
    }

    public void setEnabled(boolean enabled) {
        super.setEnabled(enabled);

        // Set the background and foreground to the combobox colors.
        if (enabled) {
            setBackground(comboBox.getBackground());
            setForeground(comboBox.getForeground());
        } else {
            setBackground(UIManager.getColor("ComboBox.disabledBackground"));
            setForeground(UIManager.getColor("ComboBox.disabledForeground"));
        }
    }

    public void paintComponent( Graphics g ) {
        boolean leftToRight = MetalUtils.isLeftToRight(comboBox);

        // Paint the button as usual
        super.paintComponent( g );

        Insets insets = getInsets();

        int width = getWidth() - (insets.left + insets.right);
        int height = getHeight() - (insets.top + insets.bottom);

        if ( height <= 0 || width <= 0 ) {
            return;
        }

        int left = insets.left;
        int top = insets.top;
        int right = left + (width - 1);
        int bottom = top + (height - 1);

        int iconWidth = 0;
        int iconLeft = (leftToRight) ? right : left;

        // Paint the icon
        if ( comboIcon != null ) {
            iconWidth = comboIcon.getIconWidth();
            int iconHeight = comboIcon.getIconHeight();
            int iconTop = 0;

            if ( iconOnly ) {
                iconLeft = (getWidth() / 2) - (iconWidth / 2);
                iconTop = (getHeight() / 2) - (iconHeight / 2);
            }
            else {
                if (leftToRight) {
                    iconLeft = (left + (width - 1)) - iconWidth;
                }
                else {
                    iconLeft = left;
                }
                iconTop = (top + ((bottom - top) / 2)) - (iconHeight / 2);
            }

            comboIcon.paintIcon( this, g, iconLeft, iconTop );

            // Paint the focus
            if ( comboBox.hasFocus() && (!MetalLookAndFeel.usingOcean() ||
                                         comboBox.isEditable())) {
                g.setColor( MetalLookAndFeel.getFocusColor() );
                g.drawRect( left - 1, top - 1, width + 3, height + 1 );
            }
        }

        if (MetalLookAndFeel.usingOcean()) {
            // With Ocean the button only paints the arrow, bail.
            return;
        }

        // Let the renderer paint
        if ( ! iconOnly && comboBox != null ) {
            ListCellRenderer renderer = comboBox.getRenderer();
            Component c;
            boolean renderPressed = getModel().isPressed();
            c = renderer.getListCellRendererComponent(listBox,
                                                      comboBox.getSelectedItem(),
                                                      -1,
                                                      renderPressed,
                                                      false);
            c.setFont(rendererPane.getFont());

            if ( model.isArmed() && model.isPressed() ) {
                if ( isOpaque() ) {
                    c.setBackground(UIManager.getColor("Button.select"));
                }
                c.setForeground(comboBox.getForeground());
            }
            else if ( !comboBox.isEnabled() ) {
                if ( isOpaque() ) {
                    c.setBackground(UIManager.getColor("ComboBox.disabledBackground"));
                }
                c.setForeground(UIManager.getColor("ComboBox.disabledForeground"));
            }
            else {
                c.setForeground(comboBox.getForeground());
                c.setBackground(comboBox.getBackground());
            }


            int cWidth = width - (insets.right + iconWidth);

            // Fix for 4238829: should lay out the JPanel.
            boolean shouldValidate = false;
            if (c instanceof JPanel)  {
                shouldValidate = true;
            }

            if (leftToRight) {
                rendererPane.paintComponent( g, c, this,
                                             left, top, cWidth, height, shouldValidate );
            }
            else {
                rendererPane.paintComponent( g, c, this,
                                             left + iconWidth, top, cWidth, height, shouldValidate );
            }
        }
    }

    public Dimension getMinimumSize() {
        Dimension ret = new Dimension();
        Insets insets = getInsets();
        ret.width = insets.left + getComboIcon().getIconWidth() + insets.right;
        ret.height = insets.bottom + getComboIcon().getIconHeight() + insets.top;
        return ret;
    }
}