A_CmsDeepLazyOpenHandler.java

/*
 * This library is part of OpenCms -
 * the Open Source Content Management System
 *
 * Copyright (c) Alkacon Software GmbH (http://www.alkacon.com)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * For further information about Alkacon Software, please see the
 * company website: http://www.alkacon.com
 *
 * For further information about OpenCms, please see the
 * project website: http://www.opencms.org
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.opencms.gwt.client.ui.tree;

import com.google.gwt.event.logical.shared.OpenEvent;

/**
 * Two levels deep lazy list tree open handler abstract implementation.<p>
 * 
 * @param <I> the specific lazy tree item implementation 
 * 
 * @since 8.0.0
 * 
 * @see org.opencms.gwt.client.ui.tree.CmsLazyTree
 * @see org.opencms.gwt.client.ui.tree.CmsLazyTreeItem
 * @see org.opencms.gwt.client.ui.tree.I_CmsLazyOpenHandler
 */
public abstract class A_CmsDeepLazyOpenHandler<I extends CmsLazyTreeItem> extends A_CmsLazyOpenHandler<I> {

    /**
     * @see org.opencms.gwt.client.ui.tree.I_CmsLazyOpenHandler#onOpen(com.google.gwt.event.logical.shared.OpenEvent)
     */
    @Override
    @SuppressWarnings("unchecked")
    public void onOpen(OpenEvent<I> event) {

        I target = event.getTarget();
        if (target.getLoadState() == CmsLazyTreeItem.LoadState.UNLOADED) {
            // in case the first level is not yet loaded
            super.onOpen(event);
        } else if (target.getChildCount() > 0) {
            // load second level
            int c = target.getChildCount();
            for (int i = 0; i < c; i++) {
                I child = (I)target.getChild(i);
                if (child.getLoadState() != CmsLazyTreeItem.LoadState.UNLOADED) {
                    continue;
                }
                child.onStartLoading();
                child.setOpen(false);
                load(child);
            }
        }
    }
}