/*
* 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;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.Widget;
/**
* Widget which wraps another widget, which will only be appended to the DOM if the wrapper's
* <code>widget()</code> method is called.<p>
*
* @param <W> the type of the widget to wrap
*
* @since 8.0.0
*/
public class CmsLazyWidgetWrapper<W extends Widget> extends Composite {
/** The wrapper panel. */
private FlowPanel m_panel;
/** The wrapped widget. */
private W m_widget;
/**
* Creates a new instance.<p>
*
* @param widget the widget to wrap
*/
public CmsLazyWidgetWrapper(W widget) {
m_panel = new FlowPanel();
initWidget(m_panel);
m_widget = widget;
}
/**
* Returns the wrapped widget and attaches it to the DOM if necessary.<p>
*
* @return the wrapped widget
*/
public W widget() {
if (m_widget.getParent() == null) {
m_panel.add(m_widget);
}
return m_widget;
}
}