org.eclipse.e4.tools.emf.ui.internal.common.TreeViewerEx.java Source code

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Here is the source code for org.eclipse.e4.tools.emf.ui.internal.common.TreeViewerEx.java

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/*******************************************************************************
 * Copyright (c) 2014 TwelveTone LLC 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:
 *     Steven Spungin <steven@spungin.tv> - initial API and implementation, Bug 396902, Bug 431847
 ******************************************************************************/

package org.eclipse.e4.tools.emf.ui.internal.common;

import java.util.ArrayList;
import java.util.List;
import org.eclipse.e4.tools.emf.ui.common.IModelResource;
import org.eclipse.e4.tools.emf.ui.internal.common.xml.EMFDocumentResourceMediator;
import org.eclipse.e4.ui.internal.workbench.E4XMIResource;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.jface.databinding.viewers.ObservableListTreeContentProvider;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocumentListener;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.swt.widgets.Composite;

/**
 * Adds additional functionality to TreeViewer
 *
 * @author Steven Spungin
 *
 */
public class TreeViewerEx extends TreeViewer {

    private ArrayList<String> elementsIds;
    private ArrayList<String> selectedIds;

    public TreeViewerEx(Composite parent, int style, EMFDocumentResourceMediator emfDocumentProvider,
            final IModelResource modelProvider) {
        super(parent, style);

        emfDocumentProvider.getDocument().addDocumentListener(new IDocumentListener() {

            @Override
            public void documentChanged(DocumentEvent event) {
                try {
                    // restore Nodes from XmiIds
                    E4XMIResource xmiResource = (E4XMIResource) ((EObject) modelProvider.getRoot().get(0))
                            .eResource();
                    ArrayList<Object> newElements = new ArrayList<Object>();
                    ObservableListTreeContentProvider provider = (ObservableListTreeContentProvider) getContentProvider();
                    Object[] children = new Object[] { modelProvider.getRoot().get(0) };
                    for (String id : elementsIds) {
                        EObject eObject = xmiResource.getEObject(id);
                        if (eObject != null) {
                            newElements.add(eObject);
                            // force tree node creation
                            getFirstMatchingItem(eObject, provider, children);
                        }
                    }
                    ArrayList<Object> newSelected = new ArrayList<Object>();
                    for (String id : selectedIds) {
                        EObject eObject = xmiResource.getEObject(id);
                        if (eObject != null) {
                            newSelected.add(eObject);
                            // force tree node creation
                            getFirstMatchingItem(eObject, provider, children);
                        }
                    }
                    setExpandedElements(newElements.toArray(new Object[0]));
                    setSelection(new StructuredSelection(newSelected));

                    // update our stored id values
                    reloadIds(modelProvider);
                } catch (Exception e) {
                    e.printStackTrace();
                }

            }

            @Override
            public void documentAboutToBeChanged(DocumentEvent event) {
                reloadIds(modelProvider);
            }

            private void reloadIds(final IModelResource modelProvider) {
                try {
                    // Stash XmiIds
                    Object[] elements = getExpandedElements();
                    List<?> selected = ((IStructuredSelection) getSelection()).toList();
                    E4XMIResource xmiResource = (E4XMIResource) ((EObject) modelProvider.getRoot().get(0))
                            .eResource();
                    elementsIds = new ArrayList<String>();
                    selectedIds = new ArrayList<String>();
                    for (Object obj : elements) {
                        if (obj instanceof EObject) {
                            elementsIds.add(xmiResource.getID((EObject) obj));
                        }
                    }
                    for (Object obj : selected) {
                        if (obj instanceof EObject) {
                            selectedIds.add(xmiResource.getID((EObject) obj));
                        }
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    // This will ensure the provider has created the tree node (so we can reveal
    // it).
    static public Object getFirstMatchingItem(EObject target, ObservableListTreeContentProvider provider,
            Object[] items) {
        for (int i = 0; i < items.length; i++) {
            if (items[i] == target) {
                return items[i];
            }
            Object found = getFirstMatchingItem(target, provider, provider.getChildren(items[i]));
            if (found != null) {
                return found;
            }
        }
        return null;
    }
}