TabsPanel.java

/*
 * Copyright 2011 Marc Grue.
 *
 * Licensed  under the  Apache License,  Version 2.0  (the "License");
 * you may not use  this file  except in  compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed  under the  License is distributed on an "AS IS" BASIS,
 * WITHOUT  WARRANTIES OR CONDITIONS  OF ANY KIND, either  express  or
 * implied.
 *
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.qi4j.sample.dcicargo.sample_a.infrastructure.wicket.tabs;

import java.util.LinkedHashMap;
import java.util.Map;
import org.apache.wicket.Application;
import org.apache.wicket.AttributeModifier;
import org.apache.wicket.MetaDataKey;
import org.apache.wicket.Page;
import org.apache.wicket.devutils.stateless.StatelessComponent;
import org.apache.wicket.markup.html.WebMarkupContainer;
import org.apache.wicket.markup.html.basic.Label;
import org.apache.wicket.markup.html.link.BookmarkablePageLink;
import org.apache.wicket.markup.html.panel.Panel;
import org.apache.wicket.markup.repeater.RepeatingView;

/**
 * Tabs panel that stores tab data as application meta data.
 */
@StatelessComponent
public class TabsPanel extends Panel
{
    public static final MetaDataKey<LinkedHashMap<Class, String[]>> TABS_PANEL_KEY = new MetaDataKey<LinkedHashMap<Class, String[]>>()
    {
        public static final long serialVersionUID = 1L;
    };

    public static <T extends Page> void registerTab( Application app, Class<T> clazz, String ref, String label )
    {
        Map<Class, String[]> tabsInfo = app.getMetaData( TABS_PANEL_KEY );

        if( tabsInfo == null || tabsInfo.isEmpty() )
        {
            tabsInfo = new LinkedHashMap<Class, String[]>();
        }

        tabsInfo.put( clazz, new String[]{ ref, label } );
        app.setMetaData( TABS_PANEL_KEY, tabsInfo );
    }

    @SuppressWarnings( "unchecked" )
    public TabsPanel( String activeTab )
    {
        super( "tabsPanel" );

        Map<Class, String[]> tabs = getApplication().getMetaData( TABS_PANEL_KEY );
        if( tabs == null || tabs.isEmpty() )
        {
            throw new RuntimeException( "Please register one or more tabs." );
        }

        RepeatingView tabsView = new RepeatingView( "tabsView" );

        // Loop "mounted" tabs
        for( Map.Entry<Class, String[]> tab : tabs.entrySet() )
        {
            Class pageClass = tab.getKey();
            String tabReference = tab.getValue()[ 0 ];
            String tabLabel = tab.getValue()[ 1 ];

            WebMarkupContainer tabView = new WebMarkupContainer( tabsView.newChildId() );
            if( tabReference.equals( activeTab ) )
            {
                tabView.add( new AttributeModifier( "id", "current" ) );
            }

            BookmarkablePageLink link = new BookmarkablePageLink( "link", pageClass );  // unchecked

            Label label = new Label( "label", tabLabel );

            tabsView.add( tabView.add( link.add( label ) ) );
        }
        add( tabsView );
    }
}