CustomPropertyEditorLayout.java

/*
 Violet - A program for editing UML diagrams.

 Copyright (C) 2007 Cay S. Horstmann (http://horstmann.com)
 Alexandre de Pellegrin (http://alexdp.free.fr);

 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package com.horstmann.violet.product.diagram.propertyeditor;

import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager;

/**
 * A layout manager that lays out components along a central axis
 */
class CustomPropertyEditorLayout implements LayoutManager
{
    public Dimension preferredLayoutSize(Container parent)
    {
        Component[] components = parent.getComponents();
        left = 0;
        right = 0;
        height = 0;
        for (int i = 0; i < components.length; i += 2)
        {
            Component cleft = components[i];
            Component cright = components[i + 1];

            Dimension dleft = cleft.getPreferredSize();
            Dimension dright = cright.getPreferredSize();
            left = Math.max(left, dleft.width);
            right = Math.max(right, dright.width);
            height = height + Math.max(dleft.height, dright.height);
        }
        return new Dimension(left + GAP + right, height);
    }

    public Dimension minimumLayoutSize(Container parent)
    {
        return preferredLayoutSize(parent);
    }

    public void layoutContainer(Container parent)
    {
        preferredLayoutSize(parent);// sets left, right

        Component[] components = parent.getComponents();

        Insets insets = parent.getInsets();
        int xcenter = insets.left + left;
        int y = insets.top;

        for (int i = 0; i < components.length; i += 2)
        {
            Component cleft = components[i];
            Component cright = components[i + 1];

            Dimension dleft = cleft.getPreferredSize();
            Dimension dright = cright.getPreferredSize();

            int height = Math.max(dleft.height, dright.height);

            cleft.setBounds(xcenter - dleft.width, y + (height - dleft.height) / 2, dleft.width, dleft.height);

            cright.setBounds(xcenter + GAP, y + (height - dright.height) / 2, dright.width, dright.height);
            y += height;
        }
    }

    public void addLayoutComponent(String name, Component comp)
    {
    }

    public void removeLayoutComponent(Component comp)
    {
    }

    private int left;
    private int right;
    private int height;
    private static final int GAP = 6;
}