WrapLayout.java

/*******************************************************************************
 * LogDruid : Generate charts and reports using data gathered in log files
 * Copyright (C) 2016 Frederic Valente (frederic.valente@gmail.com)
 *
 * 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 3 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, see http://www.gnu.org/licenses/.
 *******************************************************************************/
package logdruid.ui;

import java.awt.*;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;

public class WrapLayout extends FlowLayout {
	private Dimension preferredLayoutSize;

	public WrapLayout() {
		super();
	}

	public WrapLayout(int align) {
		super(align);
	}

	public WrapLayout(int align, int hgap, int vgap) {
		super(align, hgap, vgap);
	}

	@Override
	public Dimension preferredLayoutSize(Container target) {
		return layoutSize(target, true);
	}

	@Override
	public Dimension minimumLayoutSize(Container target) {
		Dimension minimum = layoutSize(target, false);
		minimum.width -= (getHgap() + 1);
		return minimum;
	}

	private Dimension layoutSize(Container target, boolean preferred) {
		synchronized (target.getTreeLock()) {
			int targetWidth = target.getSize().width;

			if (targetWidth == 0)
				targetWidth = Integer.MAX_VALUE;

			int hgap = getHgap();
			int vgap = getVgap();
			Insets insets = target.getInsets();
			int horizontalInsetsAndGap = insets.left + insets.right + (hgap * 2);
			int maxWidth = targetWidth - horizontalInsetsAndGap;

			Dimension dim = new Dimension(0, 0);
			int rowWidth = 0;
			int rowHeight = 0;

			int nmembers = target.getComponentCount();

			for (int i = 0; i < nmembers; i++) {
				Component m = target.getComponent(i);

				if (m.isVisible()) {
					Dimension d = preferred ? m.getPreferredSize() : m.getMinimumSize();

					if (rowWidth + d.width > maxWidth) {
						addRow(dim, rowWidth, rowHeight);
						rowWidth = 0;
						rowHeight = 0;
					}

					if (rowWidth != 0) {
						rowWidth += hgap;
					}

					rowWidth += d.width;
					rowHeight = Math.max(rowHeight, d.height);
				}
			}

			addRow(dim, rowWidth, rowHeight);

			dim.width += horizontalInsetsAndGap;
			dim.height += insets.top + insets.bottom + vgap * 2;

			Container scrollPane = SwingUtilities.getAncestorOfClass(JScrollPane.class, target);
			if (scrollPane != null) {
				dim.width -= (hgap + 1);
			}

			return dim;
		}
	}

	private void addRow(Dimension dim, int rowWidth, int rowHeight) {
		dim.width = Math.max(dim.width, rowWidth);

		if (dim.height > 0) {
			dim.height += getVgap();
		}

		dim.height += rowHeight;
	}
}