001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.ui.components.extensions;
029
030import org.opencms.ui.shared.components.CmsScrollPositionCssState;
031
032import com.vaadin.server.AbstractExtension;
033import com.vaadin.ui.AbstractComponent;
034import com.vaadin.ui.AbstractSingleComponentContainer;
035
036/**
037 * Extension to add a CSS class to any component depending on it's scroll position.<p>
038 */
039public class CmsScrollPositionCss extends AbstractExtension {
040
041    /** The serial version id. */
042    private static final long serialVersionUID = 3382283389411937891L;
043
044    /**
045     * Constructor.<p>
046     *
047     * @param componentContainer the component to extend
048     * @param scrollBarrier the scroll barrier
049     * @param barrierMargin the margin
050     * @param styleName the style name to set beyond the scroll barrier
051     */
052    public CmsScrollPositionCss(
053        AbstractComponent componentContainer,
054        int scrollBarrier,
055        int barrierMargin,
056        String styleName) {
057        super.extend(componentContainer);
058        getState().setScrollBarrier(scrollBarrier);
059        getState().setBarrierMargin(barrierMargin);
060        getState().setStyleName(styleName);
061    }
062
063    /**
064     * Adds the scroll position CSS extension to the given component
065     *
066     * @param componentContainer the component to extend
067     * @param scrollBarrier the scroll barrier
068     * @param barrierMargin the margin
069     * @param styleName the style name to set beyond the scroll barrier
070     */
071    @SuppressWarnings("unused")
072    public static void addTo(
073        AbstractSingleComponentContainer componentContainer,
074        int scrollBarrier,
075        int barrierMargin,
076        String styleName) {
077
078        new CmsScrollPositionCss(componentContainer, scrollBarrier, barrierMargin, styleName);
079    }
080
081    /**
082     * @see com.vaadin.server.AbstractClientConnector#getState()
083     */
084    @Override
085    protected CmsScrollPositionCssState getState() {
086
087        return (CmsScrollPositionCssState)super.getState();
088    }
089
090}