org.eclipse.osbp.runtime.web.vaadin.databinding/src/org/eclipse/osbp/runtime/web/vaadin/databinding/model/internal/SelectionNotifierValueChangeListener.java

/**
 * Copyright (c) 2011, 2015 - Lunifera GmbH (Gross Enzersdorf, Austria), Loetz GmbH&Co.KG (69115 Heidelberg, Germany)
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *         Florian Pirchner - Initial implementation
 */
package org.eclipse.osbp.runtime.web.vaadin.databinding.model.internal;

import org.eclipse.core.databinding.observable.Diffs;
import org.eclipse.core.databinding.observable.value.ValueDiff;
import org.eclipse.core.databinding.property.IProperty;
import org.eclipse.core.databinding.property.ISimplePropertyListener;
import org.eclipse.core.databinding.property.NativePropertyListener;
import org.eclipse.osbp.runtime.web.vaadin.databinding.properties.Util;

import com.vaadin.data.Container;
import com.vaadin.data.Container.Viewer;
import com.vaadin.data.Property;
import com.vaadin.event.SelectionEvent;

/**
 */
@SuppressWarnings("serial")
public class SelectionNotifierValueChangeListener extends
		NativePropertyListener implements
		com.vaadin.event.SelectionEvent.SelectionListener {

	private Object source;

	public SelectionNotifierValueChangeListener(IProperty property,
			ISimplePropertyListener listener) {
		super(property, listener);
	}

	protected void doAddTo(Object source) {
		this.source = source;
		getNotifier(source).addSelectionListener(this);
	}

	protected SelectionEvent.SelectionNotifier getNotifier(Object source) {
		Property<Object> property = Util.getProperty(source);
		if (property instanceof SelectionEvent.SelectionNotifier) {
			return (SelectionEvent.SelectionNotifier) property;
		} else {
			return (SelectionEvent.SelectionNotifier) source;
		}
	}

	protected Container getContainer(Object source) {
		Container.Viewer viewer = (Viewer) source;
		Container ds = viewer.getContainerDataSource();
		return ds;
	}

	protected void doRemoveFrom(Object source) {
		getNotifier(source).removeSelectionListener(this);
	}

	@Override
	public void select(SelectionEvent event) {
		Object added = event.getAdded().stream().findFirst().orElse(null);
		Object removed = event.getRemoved().stream().findFirst().orElse(null);
		ValueDiff diffs = Diffs.createValueDiff(added, removed);
		fireChange(source, diffs);
	}
}