QuaquaScrollPaneLayout.java

/*
 * @(#)QuaquaScrollPaneLayout.java  
 *
 * Copyright (c) 2005-2010 Werner Randelshofer, Immensee, Switzerland.
 * All rights reserved.
 *
 * You may not use, copy or modify this file, except in compliance with the
 * license agreement you entered into with Werner Randelshofer.
 * For details see accompanying license terms.
 */

package ch.randelshofer.quaqua;

import java.awt.*;
import javax.swing.*;
/**
 * The QuaquaScrollPaneLayout ensures that the vertical and the horizontal
 * scroll bar of a JScrollPane do not intersect with the grow-box of a
 * JFrame or a JDialog.
 * <p>
 * Note: This layout manager is only used, when we know that the grow-box
 * intrudes into frames and dialogs. Therefore we do not have to explicitly
 * check for this in this layout manager.
 *
 * @author  Werner Randelshofer
 * @version $Id: QuaquaScrollPaneLayout.java 417 2011-08-04 07:32:38Z wrandelshofer $
 */
public class QuaquaScrollPaneLayout extends ScrollPaneLayout {
     /**
     * Creates a new instance.
     */
    public QuaquaScrollPaneLayout() {
    }
    
    public void layoutContainer(Container parent) {
        super.layoutContainer(parent);
        
        // In case of a regular sized scroll pane, check if only one of the
        // scroll bars is visible
        // In case of a small or mini sized scroll pane, check if at least
        // one of the scrollbars is visible
        boolean vsbVisible = vsb != null && vsb.isVisible();
        boolean hsbVisible = hsb != null && hsb.isVisible();
        int fontSize = Math.min(parent.getFont().getSize(),
        (vsb != null && vsb.getFont() != null) ? vsb.getFont().getSize() : Integer.MAX_VALUE)
        ;
        if (fontSize >= 13 && vsbVisible != hsbVisible
        || fontSize < 13 && (vsbVisible || hsbVisible)) {
            
            // Check if the parent is on a frame or a dialog with an intruding grow-box
            JRootPane rootPane = SwingUtilities.getRootPane(parent);
            if (rootPane != null
            && (rootPane.getParent() instanceof Frame && ((Frame) rootPane.getParent()).isResizable()
            || rootPane.getParent() instanceof Dialog && ((Dialog) rootPane.getParent()).isResizable()
            )
            ) {
                // Check if the bounds of the parent intersects with the bounds
                // of the grow-box
                int x = 0;
                int y = 0;
                for(Component c = parent; c != rootPane; c = c.getParent()) {
                    // Don't avoid grow-box if we are on a JViewport
                    if (c instanceof JViewport) {
                        return;
                    }
                    x += c.getX();
                    y += c.getY();
                }
                
                Dimension growBox=UIManager.getDimension("ScrollPane.growBoxSize");
                if (growBox==null)growBox=new Dimension(0,0);
                
                if (x + parent.getWidth() > rootPane.getWidth() - growBox.width
                && y + parent.getHeight() > rootPane.getHeight() - growBox.height) {
                    Insets insets = parent.getInsets();
               
                    if (vsbVisible) {
                        vsb.setSize(
                        vsb.getWidth(), 
                        parent.getHeight() - insets.top - Math.max(insets.bottom, growBox.height)
                        );
                    }
                    if (hsbVisible) {
                        hsb.setSize(
                        parent.getWidth() - insets.left - Math.max(insets.right, growBox.width),
                        hsb.getHeight()
                        );
                    }
                }
            }
        }
    }
    
    
    
    /**
     * The UI resource version of <code>ScrollPaneLayout</code>.
     */
    public static class UIResource extends QuaquaScrollPaneLayout implements javax.swing.plaf.UIResource {}
}