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/****************************************************************************** * Copyright (c) 2002, 2008 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.editpolicies; import java.util.List; import org.eclipse.emf.ecore.EObject; import org.eclipse.emf.edit.domain.IEditingDomainProvider; import org.eclipse.emf.transaction.TransactionalEditingDomain; import org.eclipse.gef.EditPart; import org.eclipse.gef.Request; import org.eclipse.gef.commands.Command; import org.eclipse.gef.commands.CompoundCommand; import org.eclipse.gef.commands.UnexecutableCommand; import org.eclipse.gef.requests.GroupRequest; import org.eclipse.gmf.runtime.common.core.command.CompositeCommand; import org.eclipse.gmf.runtime.common.core.util.StringStatics; import org.eclipse.gmf.runtime.diagram.core.commands.DeleteCommand; import org.eclipse.gmf.runtime.diagram.core.util.ViewUtil; import org.eclipse.gmf.runtime.diagram.ui.commands.ICommandProxy; import org.eclipse.gmf.runtime.diagram.ui.editparts.GraphicalEditPart; import org.eclipse.gmf.runtime.diagram.ui.editparts.GroupEditPart; import org.eclipse.gmf.runtime.diagram.ui.editparts.IGraphicalEditPart; import org.eclipse.gmf.runtime.diagram.ui.editparts.IInsertableEditPart; import org.eclipse.gmf.runtime.diagram.ui.editparts.SemanticListCompartmentEditPart; import org.eclipse.gmf.runtime.diagram.ui.l10n.DiagramUIMessages; import org.eclipse.gmf.runtime.diagram.ui.preferences.IPreferenceConstants; import org.eclipse.gmf.runtime.diagram.ui.requests.EditCommandRequestWrapper; import org.eclipse.gmf.runtime.diagram.ui.requests.GroupRequestViaKeyboard; import org.eclipse.gmf.runtime.diagram.ui.requests.RequestConstants; import org.eclipse.gmf.runtime.emf.type.core.requests.CreateElementRequest; import org.eclipse.gmf.runtime.emf.type.core.requests.DestroyElementRequest; import org.eclipse.gmf.runtime.notation.View; import org.eclipse.jface.dialogs.IDialogConstants; import org.eclipse.jface.dialogs.MessageDialogWithToggle; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.swt.widgets.Display; /** * Concrete class that extends the GEF's <code>ComponentEditPolicy</code>. * This edit policy will return a command in response to delete requests. * * @author Vishy Ramaswamy */ public class ComponentEditPolicy extends org.eclipse.gef.editpolicies.ComponentEditPolicy { private static final String DELETE_FROM_DIAGRAM_DLG_TITLE = DiagramUIMessages.PromptingDeleteAction_DeleteFromDiagramDialog_Title; private static final String DELETE_FROM_DIAGRAM_DLG_MESSAGE = DiagramUIMessages.PromptingDeleteAction_DeleteFromDiagramDialog_Message; private static final String DELETE_FROM_MODEL_DLG_TOGGLE_LABEL = DiagramUIMessages.MessageDialogWithToggle_DoNotPromptAgainToggle_label; /** * Returns a delete command to honour the supplied request. * Calls {@link #createDeleteSemanticCommand(GroupRequest)} if * {@link #shouldDeleteSemantic()} returns <tt>true</tt>; othwerise * {@link #createDeleteViewCommand(GroupRequest)} is called. * @see org.eclipse.gef.editpolicies.ComponentEditPolicy#createDeleteCommand(GroupRequest) */ protected final Command createDeleteCommand(GroupRequest deleteRequest) { if (shouldDeleteSemantic()) { return createDeleteSemanticCommand(deleteRequest); } if (deleteRequest instanceof GroupRequestViaKeyboard) { boolean shouldShowPrompt = ((GroupRequestViaKeyboard) deleteRequest).isShowInformationDialog(); if (shouldShowPrompt) { ((GroupRequestViaKeyboard) deleteRequest).setShowInformationDialog(false); if (showPrompt() == false) { return UnexecutableCommand.INSTANCE; } } } return createDeleteViewCommand(deleteRequest); } /** * Return <tt>true</tt> if the host element should delete its semantic * element; otherwise <tt>false</tt> to delete its view. A <tt>true</tt> * return value implies that the host's parent is using a canonical * model manager. * @return true or false */ protected boolean shouldDeleteSemantic() { EditPart parent = getHost().getParent(); if (parent instanceof SemanticListCompartmentEditPart) { SemanticListCompartmentEditPart semListCompartment = (SemanticListCompartmentEditPart) parent; return semListCompartment.isCanonicalOn(); } else { // If the parent is a group, then we want to get the first parent // that isn't a group and test for a canonical editpolicy there. while (parent instanceof GroupEditPart) { parent = parent.getParent(); } } EObject eObject = (EObject) getHost().getAdapter(EObject.class); if (eObject != null && parent != null) { //sanity checks CanonicalEditPolicy cep = (CanonicalEditPolicy) parent.getEditPolicy(EditPolicyRoles.CANONICAL_ROLE); return cep != null && cep.isEnabled() && cep.canCreate(eObject); } return false; } /** * Return a command to delete the host's view. The host's primary view * is deleted if {@link GroupRequest#getEditParts()} returns a * <tt>null</tt> or empty list; otherwise each editpart's view is * deleted. * @param deleteRequest the original delete request. * @return Command */ protected Command createDeleteViewCommand(GroupRequest deleteRequest) { CompositeCommand cc = new CompositeCommand(StringStatics.BLANK); TransactionalEditingDomain editingDomain = getEditingDomain(); if (editingDomain == null) { return null; } List toDel = deleteRequest.getEditParts(); if (toDel == null || toDel.isEmpty()) { cc.compose(new DeleteCommand(editingDomain, (View) getHost().getModel())); } else { for (int i = 0; i < toDel.size(); i++) { IGraphicalEditPart gep = (IGraphicalEditPart) toDel.get(i); cc.compose(new DeleteCommand(editingDomain, (View) gep.getModel())); } } return new ICommandProxy(cc.reduce()); } /** * Return a command to delete the host's semantic elements. This method is * called if the host is canonical. * * @see #shouldDeleteSemantic() * @param deleteRequest * the original delete request. * @return Command */ protected Command createDeleteSemanticCommand(GroupRequest deleteRequest) { TransactionalEditingDomain editingDomain = ((IGraphicalEditPart) getHost()).getEditingDomain(); boolean shouldShowPrompt = (deleteRequest instanceof GroupRequestViaKeyboard) ? ((GroupRequestViaKeyboard) deleteRequest).isShowInformationDialog() : false; EditCommandRequestWrapper editCommandRequest = new EditCommandRequestWrapper( new DestroyElementRequest(editingDomain, shouldShowPrompt), deleteRequest.getExtendedData()); Command semanticCmd = getHost().getCommand(editCommandRequest); if (semanticCmd != null && semanticCmd.canExecute()) { CompoundCommand cc = new CompoundCommand(); cc.add(semanticCmd); return cc; } return createDeleteViewCommand(deleteRequest); } /** * Returns the view element to be deleted. * @return the host's primary view element. */ protected View getView() { if (getHost().getModel() instanceof View && getHost() instanceof GraphicalEditPart) { GraphicalEditPart ePart = (GraphicalEditPart) getHost(); return ePart.getPrimaryView(); } return null; } /** * Performs the delete action on the selected objects. */ private boolean showPrompt() { boolean prompt = ((IPreferenceStore) ((IGraphicalEditPart) getHost()).getDiagramPreferencesHint() .getPreferenceStore()).getBoolean(IPreferenceConstants.PREF_PROMPT_ON_DEL_FROM_DIAGRAM); if (prompt) if (showMessageDialog()) return true; else return false; return true; } /** * launches the prompting dialogBox on deletion of elements from the diagram for the end user. * * @return boolean true if user pressed YES; false otherwise */ private boolean showMessageDialog() { MessageDialogWithToggle dialog = MessageDialogWithToggle.openYesNoQuestion( Display.getCurrent().getActiveShell(), DELETE_FROM_DIAGRAM_DLG_TITLE, DELETE_FROM_DIAGRAM_DLG_MESSAGE, DELETE_FROM_MODEL_DLG_TOGGLE_LABEL, false, (IPreferenceStore) ((IGraphicalEditPart) getHost()).getDiagramPreferencesHint() .getPreferenceStore(), IPreferenceConstants.PREF_PROMPT_ON_DEL_FROM_DIAGRAM); if (dialog.getReturnCode() == IDialogConstants.YES_ID) return true; else return false; } /** * getInsertableEditPart * Returns the EditPart that can be recipient of the default insert command. * * @return IInsertableEditPart */ protected IInsertableEditPart getInsertableEditPart() { if (getHost() instanceof IInsertableEditPart) { return (IInsertableEditPart) getHost(); } return null; } /** * getInsertCommand * Returns an creation command to honour the supplied request. * * @param insertRequest * @return Command that will create the default sementic element responding to insert. */ protected Command getInsertCommand(GroupRequest insertRequest) { IInsertableEditPart insertEP = getInsertableEditPart(); if (null == insertEP) return null; EObject hostElement = ViewUtil.resolveSemanticElement((View) insertEP.getModel()); if (hostElement != null) { TransactionalEditingDomain editingDomain = getEditingDomain(); if (editingDomain == null) { return null; } CreateElementRequest theReq = new CreateElementRequest(editingDomain, hostElement, insertEP.getElementType()); EditCommandRequestWrapper editCommandRequest = new EditCommandRequestWrapper(theReq, insertRequest.getExtendedData()); Command cmd = ((IGraphicalEditPart) getHost()).getCommand(editCommandRequest); return cmd; } return null; } /* * (non-Javadoc) * * @see org.eclipse.gef.editpolicies.ComponentEditPolicy#getCommand(org.eclipse.gef.Request) */ public Command getCommand(Request request) { if (!(request instanceof GroupRequest)) return null; GroupRequest grpRequest = (GroupRequest) request; if (grpRequest instanceof GroupRequestViaKeyboard) { return getDeleteCommand(grpRequest); } else if (grpRequest.getType().equals(RequestConstants.REQ_INSERT_SEMANTIC)) { return getInsertCommand(grpRequest); } return super.getCommand(request); } private TransactionalEditingDomain getEditingDomain() { if (getHost() instanceof IGraphicalEditPart) { return ((IGraphicalEditPart) getHost()).getEditingDomain(); } else if (getHost() instanceof IEditingDomainProvider) { Object domain = ((IEditingDomainProvider) getHost()).getEditingDomain(); if (domain instanceof TransactionalEditingDomain) { return (TransactionalEditingDomain) domain; } } return null; } }