bundles/common/org.eclipse.apogy.common.emf.ui/src/org/eclipse/apogy/common/emf/ui/composites/EClassSelectionComposite.java

/*******************************************************************************
 * Copyright (c) 2018 Agence spatiale canadienne / Canadian Space Agency
 * 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:
 *     Pierre Allard - initial API and implementation
 *     Regent L'Archeveque,
 *     Olivier L. Larouche
 * 
 * SPDX-License-Identifier: EPL-1.0
 *******************************************************************************/
package org.eclipse.apogy.common.emf.ui.composites;

import org.eclipse.apogy.common.emf.ApogyCommonEMFFacade;
import org.eclipse.emf.ecore.EClass;
import org.eclipse.emf.edit.provider.ComposedAdapterFactory;
import org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider;
import org.eclipse.jface.viewers.ArrayContentProvider;
import org.eclipse.jface.viewers.ComboViewer;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;

public class EClassSelectionComposite extends Composite {
	private final ComposedAdapterFactory adapterFactory = new ComposedAdapterFactory(
			ComposedAdapterFactory.Descriptor.Registry.INSTANCE);

	private final EClass superType;
	private EClass selectedEclass;

	private final ComboViewer comboViewer;;

	public EClassSelectionComposite(Composite parent, int style) {
		this(parent, style, null);
	}

	/**
	 * 
	 * @param parent    The composite parent.
	 * @param style     The composite style.
	 * @param superType Super type for which all sub classes are to be show. Null
	 *                  shows all available EClasses.
	 */
	public EClassSelectionComposite(Composite parent, int style, EClass superType) {
		super(parent, style);
		setLayout(new FillLayout());

		this.superType = superType;

		this.comboViewer = createCombo(this, SWT.READ_ONLY);
		this.comboViewer.addSelectionChangedListener(new ISelectionChangedListener() {
			@Override
			public void selectionChanged(SelectionChangedEvent event) {
				if (event.getSelection().isEmpty()) {
					EClassSelectionComposite.this.selectedEclass = null;
					newEClassSelected(EClassSelectionComposite.this.selectedEclass);
					EClassSelectionComposite.this.comboViewer.getCombo().setToolTipText("");
				} else if (event.getSelection() instanceof IStructuredSelection) {
					IStructuredSelection iStructuredSelection = (IStructuredSelection) event.getSelection();
					if (iStructuredSelection.getFirstElement() instanceof EClass) {
						EClassSelectionComposite.this.selectedEclass = (EClass) iStructuredSelection.getFirstElement();
						EClassSelectionComposite.this.comboViewer.getCombo().setToolTipText(
								EClassSelectionComposite.this.selectedEclass.getInstanceClass().getName());
						newEClassSelected(EClassSelectionComposite.this.selectedEclass);
					} else {
						EClassSelectionComposite.this.selectedEclass = null;
						EClassSelectionComposite.this.comboViewer.getCombo().setToolTipText("");
						newEClassSelected(EClassSelectionComposite.this.selectedEclass);
					}
				}
			}
		});
	}

	public ComboViewer getComboViewer() {
		return this.comboViewer;
	}

	public EClass getSelectedEclass() {
		return this.selectedEclass;
	}

	public void select(EClass eClass) {
		if (this.comboViewer != null && !this.comboViewer.getCombo().isDisposed()) {
			if (eClass != null) {
				this.comboViewer.setSelection(new StructuredSelection(eClass), true);
			} else {
				this.comboViewer.setSelection(new StructuredSelection(), true);
			}
		}
	}

	private ComboViewer createCombo(Composite parent, int style) {
		ComboViewer comboViewer = new ComboViewer(parent, SWT.DROP_DOWN);
		comboViewer.setContentProvider(ArrayContentProvider.getInstance());
		comboViewer.setLabelProvider(new AdapterFactoryLabelProvider(this.adapterFactory));

		// Display the combo element sorted by displayed name.
		comboViewer.setComparator(new ViewerComparator() {
			@Override
			public int compare(Viewer viewer, Object e1, Object e2) {
				EClass eClass1 = (EClass) e1;
				EClass eClass2 = (EClass) e2;

				String name1 = eClass1.getName();
				String name2 = eClass2.getName();

				return name1.compareTo(name2);
			}
		});

		if (this.superType != null) {
			comboViewer.setInput(ApogyCommonEMFFacade.INSTANCE.getAllSubEClasses(this.superType));
		} else {
			comboViewer.setInput(ApogyCommonEMFFacade.INSTANCE.getAllAvailableEClasses());
		}

		return comboViewer;
	}

	protected void newEClassSelected(EClass newEclass) {
	}
}