UpDownPanel.java

/* (c) 2014 - 2016 Open Source Geospatial Foundation - all rights reserved
 * (c) 2001 - 2013 OpenPlans
 * This code is licensed under the GPL 2.0 license, available at the root
 * application directory.
 */
package org.geoserver.web.wicket;

import java.util.List;

import org.apache.wicket.AttributeModifier;
import org.apache.wicket.Component;
import org.apache.wicket.ajax.AjaxRequestTarget;
import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.html.panel.Panel;
import org.apache.wicket.model.StringResourceModel;
import org.apache.wicket.request.resource.PackageResourceReference;

/**
 * A panel with two arrows, up and down, supposed to reorder items in a container (a table)
 * 
 * @author Andrea Aime - GeoSolutions
 * 
 * @param <T>
 */
public class UpDownPanel<T extends Object> extends Panel {
    
    private static final long serialVersionUID = -5964561496724645286L;
    T entry;
    private ImageAjaxLink<?> upLink;

    private ImageAjaxLink<?> downLink;

    private Component container;
    
    public UpDownPanel(String id, final T entry, final List<T> items, Component container,
            final StringResourceModel upTitle, final StringResourceModel downTitle) {
        super( id );
        this.entry = entry;
        this.setOutputMarkupId(true);
        this.container = container;
        
        upLink = new ImageAjaxLink<Void>("up", new PackageResourceReference(getClass(),
                "../img/icons/silk/arrow_up.png")) {
            private static final long serialVersionUID = 2377129539852597050L;

            @Override
            protected void onClick(AjaxRequestTarget target) {
                int index = items.indexOf( UpDownPanel.this.entry );
                items.remove( index );
                items.add(Math.max(0, index - 1), UpDownPanel.this.entry);
                target.add(UpDownPanel.this.container);
                target.add(this);
                target.add(downLink);   
                target.add(upLink);                    
            }
            
            @Override
            protected void onComponentTag(ComponentTag tag) {
                tag.put("title", upTitle.getString());
                if ( items.indexOf( entry ) == 0 ) {
                    tag.put("style", "visibility:hidden");
                } else {
                    tag.put("style", "visibility:visible");
                }
            }
        };
        upLink.getImage().add(new AttributeModifier("alt", new ParamResourceModel("up", upLink)));
        upLink.setOutputMarkupId(true);
        add( upLink);            

        downLink = new ImageAjaxLink<Void>("down", new PackageResourceReference(getClass(),
                "../img/icons/silk/arrow_down.png")) {
            private static final long serialVersionUID = -1770135905138092575L;

            @Override
            protected void onClick(AjaxRequestTarget target) {
                int index = items.indexOf( UpDownPanel.this.entry );
                items.remove( index );
                items.add(Math.min(items.size(), index + 1), UpDownPanel.this.entry);
                target.add(UpDownPanel.this.container);
                target.add(this);                    
                target.add(downLink);   
                target.add(upLink);                    
            }
            
            @Override
            protected void onComponentTag(ComponentTag tag) {
                tag.put("title", downTitle.getString());
                if ( items.indexOf( entry ) == items.size() - 1) {
                    tag.put("style", "visibility:hidden");
                } else {
                    tag.put("style", "visibility:visible");
                }
            }
        };
        downLink.getImage().add(new AttributeModifier("alt", new ParamResourceModel("down", downLink)));
        downLink.setOutputMarkupId(true);
        add( downLink);
    }
}