/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2001 Intersect Software Corporation

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.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.ui;

import net.wotonomy.foundation.NSArray;

/**
 * This master detail association synchronizes the contents and selection of the
 * master group into the detail group.
 */
public class MirrorDetailAssociation extends MasterDetailAssociation {

	/**
	 * Standard constructor specifying the detail display group.
	 * 
	 * @param displayGroup the detail display group of this Master-Detail
	 *                     Association
	 */
	public MirrorDetailAssociation(EODisplayGroup displayGroup) {
		super(displayGroup);
	}

	/**
	 * Called by subjectChanged() to requalify the controlled display group with the
	 * indexed object and the bound key. This implementation ignores both and sets
	 * the object array of the detail group to the displayed objects of the master
	 * and sets the selection to match.
	 */
	protected void requalify() {
		EODisplayGroup detail = (EODisplayGroup) object();
		EODisplayGroup master = displayGroupForAspect(ParentAspect);

		if (master != null) {
			NSArray masterObjects = master.displayedObjects();
			NSArray detailObjects = detail.displayedObjects();
			int size = masterObjects.size();
			boolean different = false;

			// see if lists contain the same object instances
			if (size == detailObjects.size()) {
				for (int i = 0; i < size; i++) {
					if (masterObjects.objectAtIndex(i) != detailObjects.objectAtIndex(i)) {
						different = true;
						break;
					}
				}
			} else // different sizes
			{
				different = true;
			}

			// if different, sync contents and selection with master
			if (different) {
				detail.setObjectArray(masterObjects);
				detail.setSelectionIndexes(master.selectionIndexes());
			} else // if selection changed, sync selection with master
			if (master.selectionChanged()) {
				detail.setSelectionIndexes(master.selectionIndexes());
			}
		} else // no bound display group, clear
		{
			detail.setObjectArray(null);
		}
	}
}
/*
 * $Log$ Revision 1.1 2006/02/16 13:22:22 cgruber Check in all sources in
 * eclipse-friendly maven-enabled packages.
 *
 * Revision 1.2 2001/07/05 22:13:28 mpowers Now only updating if master has
 * actually changed.
 *
 * Revision 1.1 2001/05/29 19:57:47 mpowers Added some neglected files.
 *
 *
 */