de.topicmapslab.tmcledit.model.actions.DeleteDiagramAction.java Source code

Introduction

Here is the source code for de.topicmapslab.tmcledit.model.actions.DeleteDiagramAction.java

Source

/*******************************************************************************
 * Copyright (c) 2008, 2009 Topic Maps Lab and others.
 * 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:
 *     Hannes Niederhausen - initial API and implementation
 *******************************************************************************/
/**
 * 
 */
package de.topicmapslab.tmcledit.model.actions;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

import org.eclipse.emf.common.command.CompoundCommand;
import org.eclipse.jface.action.Action;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.swt.widgets.Shell;

import de.topicmapslab.tmcledit.model.Diagram;
import de.topicmapslab.tmcledit.model.TmcleditEditPlugin;
import de.topicmapslab.tmcledit.model.commands.DeleteDiagramCommand;
import de.topicmapslab.tmcledit.model.views.ModelView;

/**
 * Action to delete adiagram in the {@link ModelView}
 * 
 * @author Hannes Niederhausen
 * 
 */
public class DeleteDiagramAction extends Action implements ISelectionChangedListener {

    private List<Diagram> diagrams;
    private ModelView modelView;

    /**
     * 
     * @param modelView the {@link ModelView}
     */
    public DeleteDiagramAction(ModelView modelView) {
        setText("Delete");
        this.modelView = modelView;
        diagrams = new ArrayList<Diagram>();
        TmcleditEditPlugin.getPlugin().getOnotoaSelectionService().addSelectionChangedListener(this);
        setDiagram(null);
    }

    /**
     * Sets the diagram to delete
     * @param sel a selection containing one or more {@link Diagram}s
     */
    public void setDiagram(IStructuredSelection sel) {
        diagrams.clear();
        if (sel != null) {
            Iterator it = sel.iterator();

            while (it.hasNext()) {
                Object o = it.next();
                if (o instanceof Diagram) {
                    diagrams.add((Diagram) o);
                }
            }
        }
        setEnabled(!diagrams.isEmpty());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void run() {
        Shell shell = modelView.getSite().getShell();
        if (MessageDialog.openQuestion(shell, "Are you sure?",
                "Do you really want to delete the selected diagram?")) {

            CompoundCommand ccmd = new CompoundCommand();

            List<DeleteDiagramCommand> cmdList = new ArrayList<DeleteDiagramCommand>();
            for (Diagram d : diagrams) {
                DeleteDiagramCommand cmd = new DeleteDiagramCommand(d);
                cmdList.add(cmd);
            }

            // sorting commands, so the diagram deletion can be undone (command uses position in
            // diagram list therefor the diagrams with the lower indices need to be deleted last)
            Collections.sort(cmdList, new Comparator<DeleteDiagramCommand>() {

                public int compare(DeleteDiagramCommand o1, DeleteDiagramCommand o2) {
                    if (o1.getIndex() == o2.getIndex())
                        return 0;
                    if (o1.getIndex() < o2.getIndex())
                        return 1;
                    else
                        return -1;
                }

            });
            for (DeleteDiagramCommand cmd : cmdList)
                ccmd.append(cmd);

            modelView.getEditingDomain().getCommandStack().execute(ccmd);
        }

    }

    /**
     * {@inheritDoc}
     */
    public void selectionChanged(SelectionChangedEvent event) {
        setDiagram((IStructuredSelection) event.getSelection());
    }
}