CRFlowLayout.java

/**
 * OrbisGIS is a java GIS application dedicated to research in GIScience.
 * OrbisGIS is developed by the GIS group of the DECIDE team of the 
 * Lab-STICC CNRS laboratory, see <http://www.lab-sticc.fr/>.
 *
 * The GIS group of the DECIDE team is located at :
 *
 * Laboratoire Lab-STICC – CNRS UMR 6285
 * Equipe DECIDE
 * UNIVERSITÉ DE BRETAGNE-SUD
 * Institut Universitaire de Technologie de Vannes
 * 8, Rue Montaigne - BP 561 56017 Vannes Cedex
 * 
 * OrbisGIS is distributed under GPL 3 license.
 *
 * Copyright (C) 2007-2014 CNRS (IRSTV FR CNRS 2488)
 * Copyright (C) 2015-2017 CNRS (Lab-STICC UMR CNRS 6285)
 *
 * This file is part of OrbisGIS.
 *
 * OrbisGIS 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.
 *
 * OrbisGIS 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
 * OrbisGIS. If not, see <http://www.gnu.org/licenses/>.
 *
 * For more information, please consult: <http://www.orbisgis.org/>
 * or contact directly:
 * info_at_ orbisgis.org
 */
package org.orbisgis.sif;

import java.awt.*;

public class CRFlowLayout extends FlowLayout {

	public CRFlowLayout(int alignment) {
		super(alignment);
	}

	public CRFlowLayout() {
	}

	@Override
	public void layoutContainer(Container target) {
		synchronized (target.getTreeLock()) {
			Insets insets = target.getInsets();
			int maxwidth = target.getWidth()
					- (insets.left + insets.right + getHgap() * 2);
			int nmembers = target.getComponentCount();
			int x = 0, y = insets.top + getVgap();
			int rowh = 0, start = 0;

			boolean ltr = target.getComponentOrientation().isLeftToRight();

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

					if (m instanceof Container) {
						if (((Container) m).getLayout() instanceof CRFlowLayout) {
							layoutContainer((Container) m);
						}
					}

					Dimension d = m.getPreferredSize();
					m.setSize(d.width, d.height);

					if (((x == 0) || ((x + d.width) <= maxwidth))
							&& !(m instanceof CarriageReturn)) {
						if (x > 0) {
							x += getHgap();
						}
						x += d.width;
						rowh = Math.max(rowh, d.height);
					} else {
						moveComponents(target, insets.left + getHgap(), y,
								maxwidth - x, rowh, start, i, ltr);
						x = d.width;
						y += getVgap() + rowh;
						rowh = d.height;
						start = i;
					}
				}
			}
			moveComponents(target, insets.left + getHgap(), y, maxwidth - x,
					rowh, start, nmembers, ltr);
		}
	}

	@Override
	public Dimension preferredLayoutSize(Container target) {
		synchronized (target.getTreeLock()) {
			Dimension dim = new Dimension(0, 0);
			int nmembers = target.getComponentCount();
			boolean firstVisibleComponent = true;
			boolean newLine = true;
			boolean firstLine = true;
			int x = 0;
			int y = 0;

			for (int i = 0; i < nmembers; i++) {
				Component m = target.getComponent(i);
				if (m.isVisible()) {
					Dimension d = m.getPreferredSize();
					if (!(m instanceof CarriageReturn)) {
						if (firstVisibleComponent) {
							firstVisibleComponent = false;
						} else {
							x += getHgap();
							y = Math.max(y, d.height);
						}
						x += d.width;
					}
					if (newLine) {
						if (!firstLine) {
							dim.height += getVgap();
						}
						firstLine = false;
						y += d.height;
						newLine = false;
					}

					if (m instanceof CarriageReturn) {
						dim.height += y;
						y = 0;
						dim.width = Math.max(x, dim.width);
						x = 0;
						newLine = true;
						firstVisibleComponent = true;
					}
				}
			}
			dim.height += y;
			dim.width = Math.max(x, dim.width);

			Insets insets = target.getInsets();
			dim.width += insets.left + insets.right + getHgap() * 2;
			dim.height += insets.top + insets.bottom + getVgap() * 2;
			return dim;
		}
	}

	/**
	 * Centers the elements in the specified row, if there is any slack.
	 * 
	 * @param target
	 *            the component which needs to be moved
	 * @param x
	 *            the x coordinate
	 * @param y
	 *            the y coordinate
	 * @param width
	 *            the width dimensions
	 * @param height
	 *            the height dimensions
	 * @param rowStart
	 *            the beginning of the row
	 * @param rowEnd
	 *            the the ending of the row
	 */
	private void moveComponents(Container target, int x, int y, int width,
			int height, int rowStart, int rowEnd, boolean ltr) {
		synchronized (target.getTreeLock()) {
			switch (getAlignment()) {
			case LEFT:
				x += ltr ? 0 : width;
				break;
			case CENTER:
				x += width / 2;
				break;
			case RIGHT:
				x += ltr ? width : 0;
				break;
			case LEADING:
				break;
			case TRAILING:
				x += width;
				break;
			}
			for (int i = rowStart; i < rowEnd; i++) {
				Component m = target.getComponent(i);
				if (m instanceof CarriageReturn)
					continue;
				if (m.isVisible()) {
					if (ltr) {
						m.setLocation(x, y + (height - m.getHeight()) / 2);
					} else {
						m.setLocation(target.getWidth() - x - m.getWidth(), y
								+ (height - m.getHeight()) / 2);
					}
					x += m.getWidth() + getHgap();
				}
			}
		}
	}

}