org.eclipse.gmf.runtime.diagram.ui/src/org/eclipse/gmf/runtime/diagram/ui/tools/AbstractPopupBarTool.java

/******************************************************************************
 * Copyright (c) 2004, 2006 IBM Corporation 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:
 *    IBM Corporation - initial API and implementation 
 ****************************************************************************/

package org.eclipse.gmf.runtime.diagram.ui.tools;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.gef.DragTracker;
import org.eclipse.gef.EditPart;
import org.eclipse.gef.EditPartViewer;
import org.eclipse.gef.Request;
import org.eclipse.gef.RequestConstants;
import org.eclipse.gef.commands.Command;
import org.eclipse.gef.requests.CreateRequest;
import org.eclipse.gef.tools.TargetingTool;
import org.eclipse.gmf.runtime.diagram.core.preferences.PreferencesHint;
import org.eclipse.gmf.runtime.diagram.ui.editparts.IGraphicalEditPart;
import org.eclipse.gmf.runtime.diagram.ui.parts.DiagramCommandStack;
import org.eclipse.gmf.runtime.emf.type.core.IElementType;
import org.eclipse.gmf.runtime.notation.View;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.swt.widgets.Display;

/**
 * Abstract class for popup bar tools. This is the tool used for the Add
 * commands associated with the popup bars. The creation tools for popup bars
 * also need to impl DragTracker since the SelectionTool calls
 * Handle.getDragTracker during mouseDown.
 * 
 * @author affrantz
 */

public abstract class AbstractPopupBarTool
	extends TargetingTool
	implements DragTracker {

	private EditPart myHostEditPart = null;

	/** the requested element kind */
    private IElementType myElementType = null;

	/** the create request to be used (optional) */
    private CreateRequest myRequest = null;

    /**
	 * @param epHost
	 *            the host editpart
	 * @param elementType
	 *            the element type to be created
	 */
	public AbstractPopupBarTool(EditPart epHost, IElementType elementType) {
		myElementType = elementType;
		myHostEditPart = epHost;
		lockTargetEditPart(epHost);
	}

	/**
	 * @param epHost
	 *            the host editpart
	 * @param theRequest
	 *            the create request to be used
	 */
	public AbstractPopupBarTool(EditPart epHost, CreateRequest theRequest) {
		myHostEditPart = epHost;
		myRequest = theRequest;
		lockTargetEditPart(epHost);
	}

	/**
	 * @see org.eclipse.gef.tools.TargetingTool#createTargetRequest()
	 */
	abstract protected Request createTargetRequest();

	/**
	 * @see org.eclipse.gef.tools.TargetingTool#getCommand()
	 */
	abstract protected Command getCommand();

	/**
	 * Test to see if the tool's associated cmd is available to be run
	 */
	public boolean isCommandEnabled() {
		Command cmd = this.getCommand();
		if (cmd == null) {
			return false;
		}

		return cmd.canExecute();
	}

	/**
	 * @see org.eclipse.gef.DragTracker#commitDrag()
	 */
	public void commitDrag() {
		// NULL implementation
	}

	protected boolean handleButtonDown(int button) {
		// push the cmd that will be used by performCreation
		setCurrentCommand(getCommand());
		return super.handleButtonDown(button);

	}

	/**
	 * 
	 * @see org.eclipse.gef.tools.AbstractTool#handleButtonUp(int)
	 */
	protected boolean handleButtonUp(int button) {
		performCreation(button);

		return true;
	}

	/**
	 * @see org.eclipse.gef.tools.AbstractTool#performCreation(int)
	 * @param button
	 */
	private void performCreation(int button) {
		EditPartViewer viewer = getCurrentViewer();
		Command c = getCurrentCommand();
		executeCurrentCommand();

		List editparts = new ArrayList(1);
		Collection newObjects = DiagramCommandStack.getReturnValues(c);
		for (Iterator i = newObjects.iterator(); i.hasNext();) {
			Object o = i.next();
			EditPart editpart = null;
			if (o instanceof IAdaptable) {
				IAdaptable adapter = (IAdaptable) o;
				View view = (View) adapter.getAdapter(View.class);
				if (view != null)
					editpart = (EditPart) viewer.getEditPartRegistry()
						.get(view);
			} else if (o instanceof EObject) {
				IGraphicalEditPart host = (IGraphicalEditPart) myHostEditPart;
				editpart = host.findEditPart(host, (EObject) o);
			}
			if (editpart != null)
				editparts.add(editpart);
		}
		selectAddedObject(viewer, editparts);
	}

	/**
	 * Finds the newly created editpart associated with the element that has
	 * been added and then selects the editpart and requests direct editing
	 * 
	 */
	protected void selectAddedObject(final EditPartViewer viewer,
			final List editparts) {
		if (editparts.isEmpty())
			return;
        
        // Don't change the selection unless at least one editpart is
        // selectable.
        boolean selectable = false;
        for (Iterator iter = editparts.iterator(); iter.hasNext();) {
            EditPart editpart = (EditPart) iter.next();
            if (editpart.isSelectable()) {
                selectable = true;
                break;
            }
         }
        
        if (selectable) {
    		// automatically put the first shape into edit-mode
    		Display.getCurrent().asyncExec(new Runnable() {
    
    			public void run() {
    				viewer.setSelection(new StructuredSelection(editparts));
    				EditPart editpart = (EditPart) editparts.get(0);
    				editpart.performRequest(new Request(
    					RequestConstants.REQ_DIRECT_EDIT));
    			}
    		});
        }
	}

	/**
	 * HACK in order to lock the editpart for the duration that this tool is
	 * active and avoid updateTargetUnderMouse, getting called we need to
	 * override this method to perform a NOP
	 * 
	 * @see org.eclipse.gef.tools.TargetingTool#unlockTargetEditPart()
	 */
	protected void unlockTargetEditPart() {
		// NULL implementation
	}

	protected IElementType getElementType() {
		return myElementType;
	}

	protected void setElementKind(IElementType elementType) {
		myElementType = elementType;
	}

	/**
	 * @see org.eclipse.gef.tools.AbstractTool#getCommandName()
	 */
	protected String getCommandName() {
		return REQ_CREATE;

	}

	/**
	 * @see org.eclipse.gef.tools.AbstractTool#getDebugName()
	 */
	protected String getDebugName() {
		return "Popup Bar Creation Tool"; //$NON-NLS-1$

	}

	protected EditPart getHost() {
		return myHostEditPart;
	}

	/**
	 * Gets the preferences hint that is to be used to find the appropriate
	 * preference store from which to retrieve diagram preference values. The
	 * preference hint is mapped to a preference store in the preference
	 * registry <@link DiagramPreferencesRegistry>.
	 * 
	 * @return the preferences hint
	 */
	protected PreferencesHint getPreferencesHint() {
		PreferencesHint preferencesHint = null;
		if (myHostEditPart != null) {
			preferencesHint = ((IGraphicalEditPart) myHostEditPart)
				.getDiagramPreferencesHint();
		}
		return preferencesHint;
	}
        
    /**
     * Gets the the create request to be used if one was specified in the constructor.
     * @return Returns the create request.
     */
    protected CreateRequest getCreateRequest() {
        return myRequest;
    }
}