plugins/org.eclipse.eef.ide.ui/src/org/eclipse/eef/ide/ui/api/widgets/AbstractEEFWidgetLifecycleManager.java - eef/org.eclipse.eef - Git at Google

 /*******************************************************************************
  * Copyright (c) 2016, 2018 Obeo.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors: Obeo - initial API and implementation
  *******************************************************************************/
 package org.eclipse.eef.ide.ui.api.widgets;

 import java.util.Collection;
 import java.util.Optional;
 import java.util.function.Consumer;

 import org.eclipse.eef.EEFDynamicMappingFor;
 import org.eclipse.eef.EEFDynamicMappingIf;
 import org.eclipse.eef.EEFGroupDescription;
 import org.eclipse.eef.EEFWidgetDescription;
 import org.eclipse.eef.EEFWidgetStyle;
 import org.eclipse.eef.common.api.utils.Util;
 import org.eclipse.eef.common.ui.api.EEFWidgetFactory;
 import org.eclipse.eef.common.ui.api.IEEFFormContainer;
 import org.eclipse.eef.core.api.EEFExpressionUtils;
 import org.eclipse.eef.core.api.EditingContextAdapter;
 import org.eclipse.eef.core.api.LockStatusChangeEvent;
 import org.eclipse.eef.core.api.LockStatusChangeEvent.LockStatus;
 import org.eclipse.eef.core.api.controllers.IEEFWidgetController;
 import org.eclipse.eef.core.api.utils.EvalFactory;
 import org.eclipse.eef.ide.ui.api.widgets.EEFStyleHelper.IEEFTextStyleCallback;
 import org.eclipse.eef.ide.ui.internal.EEFIdeUiPlugin;
 import org.eclipse.eef.ide.ui.internal.Icons;
 import org.eclipse.eef.ide.ui.internal.Messages;
 import org.eclipse.eef.ide.ui.internal.widgets.EEFStyledTextStyleCallback;
 import org.eclipse.eef.ide.ui.internal.widgets.styles.EEFColor;
 import org.eclipse.eef.ide.ui.internal.widgets.styles.EEFFont;
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.jface.fieldassist.ControlDecoration;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.jface.viewers.StructuredViewer;
 import org.eclipse.sirius.common.interpreter.api.IInterpreter;
 import org.eclipse.sirius.common.interpreter.api.IVariableManager;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.CLabel;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.events.MouseEvent;
 import org.eclipse.swt.events.MouseTrackListener;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.Font;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Display;

 /**
  * Parent of all the lifecycle managers.
  *
  * @author sbegaudeau
  */
 public abstract class AbstractEEFWidgetLifecycleManager extends AbstractEEFLifecycleManager {
 	/**
 	 * The number of pixel of the additional gap necessary to draw the validation marker.
 	 */
 	protected static final int VALIDATION_MARKER_OFFSET = 5;

 	/**
 	 * The variable manager.
 	 */
 	protected IVariableManager variableManager;

 	/**
 	 * The interpreter.
 	 */
 	protected IInterpreter interpreter;

 	/**
 	 * The editing context adapter.
 	 */
 	protected EditingContextAdapter editingContextAdapter;

 	/**
 	 * The label.
 	 */
 	protected StyledText label;

 	/**
 	 * The help label.
 	 */
 	protected CLabel help;

 	/**
 	 * The listener on the help.
 	 */
 	private MouseTrackListener mouseTrackListener;

 	/**
 	 * The listener used to react to changes in the lock status of a semantic element.
 	 */
 	private Consumer<Collection<LockStatusChangeEvent>> lockStatusChangedListener;

 	/**
 	 * The decorator used to indicate the permission on the validation widget.
 	 */
 	private ControlDecoration controlDecoration;

 	/**
 	 * The constructor.
 	 *
 	 * @param variableManager
 	 *            The variable manager
 	 * @param interpreter
 	 *            The interpreter
 	 * @param editingContextAdapter
 	 *            The editing context adapter
 	 */
 	public AbstractEEFWidgetLifecycleManager(IVariableManager variableManager, IInterpreter interpreter,
 			EditingContextAdapter editingContextAdapter) {
 		this.variableManager = variableManager;
 		this.interpreter = interpreter;
 		this.editingContextAdapter = editingContextAdapter;
 	}

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#createControl(org.eclipse.swt.widgets.Composite,
 	 *          org.eclipse.eef.common.ui.api.IEEFFormContainer)
 	 */
 	@Override
 	public void createControl(Composite parent, IEEFFormContainer formContainer) {
 		super.createControl(parent, formContainer);

 		EEFWidgetFactory widgetFactory = formContainer.getWidgetFactory();

 		Composite composite = parent;

 		// If we are in a group, we will always create a label (empty or not) for the 3 columns layout of the group.
 		boolean isInGroup = this.isInGroup();

 		// Some widgets (like a checkbox) will not have a separated "label" widget for their label. Those widgets will
 		// thus never create another widget expect in the group (for the layout).
 		boolean needsSeparatedLabel = this.needSeparatedLabel();

 		// Finally if the label expression is blank, we will not create a label inside of a group (for the layout).
 		boolean isBlankLabel = Util.isBlank(this.getWidgetDescription().getLabelExpression());

 		boolean needsLabel = isInGroup || (!isBlankLabel && needsSeparatedLabel);
 		boolean needsHelp = isInGroup || !Util.isBlank(this.getWidgetDescription().getHelpExpression());

 		// If we are not in a group, we will create a composite to hold all the label and help of the widget if
 		// necessary
 		if (!isInGroup && (needsLabel || needsHelp)) {
 			composite = widgetFactory.createComposite(parent);

 			// We will only create the necessary number of columns for this "invisible" composite
 			int numColumn = 1;
 			if (needsLabel) {
 				numColumn = numColumn + 1;
 			}
 			if (needsHelp) {
 				numColumn = numColumn + 1;
 			}
 			GridLayout layout = new GridLayout(numColumn, false);
 			// As this composite is "invisible", it must not add border.
 			layout.marginHeight = 0;
 			layout.marginWidth = 0;
 			composite.setLayout(layout);

 			GridData layoutData = new GridData(GridData.FILL_HORIZONTAL);
 			layoutData.horizontalSpan = 1;
 			composite.setLayoutData(layoutData);
 		}

 		if (needsLabel) {
 			this.label = widgetFactory.createStyledText(composite, SWT.READ_ONLY);
 			this.label.setEditable(false);
 			this.label.setCaret(null);
 			this.label.setCursor(Display.getCurrent().getSystemCursor(SWT.CURSOR_ARROW));
 			this.label.setDoubleClickEnabled(false);
 			this.label.setLayoutData(new GridData(this.getLabelVerticalAlignment()));
 		}

 		if (needsHelp) {
 			this.help = widgetFactory.createCLabel(composite, ""); //$NON-NLS-1$
 			if (!Util.isBlank(this.getWidgetDescription().getHelpExpression())) {
 				this.help.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.HELP));
 				this.help.setLayoutData(new GridData(this.getLabelVerticalAlignment()));
 				this.help.setToolTipText(""); //$NON-NLS-1$
 			}
 		}

 		this.createMainControl(composite, formContainer);

 		this.controlDecoration = new ControlDecoration(this.getValidationControl(), SWT.TOP | SWT.LEFT);
 		this.checkLockStatus();
 	}

 	/**
 	 * Checks the current lock status and make the user interface react to it.
 	 */
 	private void checkLockStatus() {
 		Object self = this.variableManager.getVariables().get(EEFExpressionUtils.SELF);
 		if (self instanceof EObject) {
 			LockStatus status = this.editingContextAdapter.getLockStatus((EObject) self);
 			this.handleLockStatus(status);
 		}
 	}

 	/**
 	 * Indicates if the widget description is located directly under a group or if it is under a container.
 	 *
 	 * @return <code>true</code> if the widget description is directly under a group, <code>false</code> otherwise
 	 */
 	private boolean isInGroup() {
 		EObject eContainer = this.getWidgetDescription().eContainer();

 		// Test if the widget description is in a dynamic mapping directly under a group
 		if (eContainer instanceof EEFDynamicMappingIf && eContainer.eContainer() instanceof EEFDynamicMappingFor) {
 			EEFDynamicMappingFor dynamicMappingFor = (EEFDynamicMappingFor) eContainer.eContainer();
 			return dynamicMappingFor.eContainer() instanceof EEFGroupDescription;
 		}

 		// Otherwise, let's test if it is directly under a group
 		return eContainer instanceof EEFGroupDescription;
 	}

 	/**
 	 * Indicates if the widget should create a label widget for its label.
 	 *
 	 * @return <code>true</code> if a label should be created, <code>false</code> otherwise.
 	 */
 	protected boolean needSeparatedLabel() {
 		return true;
 	}

 	/**
 	 * Returns the vertical alignment of the label of the widget. Use one of the following values:
 	 * <ul>
 	 * <li>GridData.VERTICAL_ALIGN_BEGINNING</li>
 	 * <li>GridData.VERTICAL_ALIGN_CENTER</li>
 	 * <li>GridData.VERTICAL_ALIGN_END</li>
 	 * </ul>
 	 *
 	 * @return The vertical alignment of the label of the widget
 	 */
 	protected int getLabelVerticalAlignment() {
 		// By default, the label is aligned to the top of the widget
 		return GridData.VERTICAL_ALIGN_BEGINNING;
 	}

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#getController()
 	 */
 	@Override
 	protected abstract IEEFWidgetController getController();

 	/**
 	 * Returns the description of the widget.
 	 *
 	 * @return The description of the widget
 	 */
 	protected abstract EEFWidgetDescription getWidgetDescription();

 	/**
 	 * Create the main control.
 	 *
 	 * @param parent
 	 *            The composite parent
 	 * @param formContainer
 	 *            The form container
 	 */
 	protected abstract void createMainControl(Composite parent, IEEFFormContainer formContainer);

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#aboutToBeShown()
 	 */
 	@Override
 	public void aboutToBeShown() {
 		super.aboutToBeShown();

 		this.getController().onNewLabel((value) -> {
 			if (!label.isDisposed() && !(label.getText() != null && label.getText().equals(value))) {
 				label.setText(Optional.ofNullable(value).orElse("")); //$NON-NLS-1$
 			}
 			AbstractEEFWidgetLifecycleManager.this.setLabelFontStyle();
 		});

 		this.getController().onNewHelp((value) -> {
 			if (help != null && !help.isDisposed() && !(help.getText() != null && help.getText().equals(value))) {
 				help.setToolTipText(Optional.ofNullable(value).orElse(Messages.AbstractEEFWidgetLifecycleManager_noDescriptionAvailable));
 			}
 		});

 		if (this.help != null) {
 			this.mouseTrackListener = new MouseTrackListener() {

 				@Override
 				public void mouseHover(MouseEvent e) {
 					// Defer the computation of the help message when the user hovers the Help label
 					getController().computeHelp();
 				}

 				@Override
 				public void mouseExit(MouseEvent e) {
 					// Nothing todo
 				}

 				@Override
 				public void mouseEnter(MouseEvent e) {
 					// Nothing todo
 				}
 			};
 			this.help.addMouseTrackListener(mouseTrackListener);
 		}

 		this.lockStatusChangedListener = (events) -> {
 			Display.getDefault().asyncExec(() -> {
 				events.stream().filter(event -> this.getWidgetSemanticElement().equals(event.getElement()))
 						.forEach(event -> this.handleLockStatus(event.getStatus()));
 			});
 		};
 		this.editingContextAdapter.addLockStatusChangedListener(this.lockStatusChangedListener);
 	}

 	/**
 	 * Handles the change in the lock status by switching the user interface to a "locked by me", "locked by other" or
 	 * "unlocked" state.
 	 *
 	 * @param status
 	 *            The lock status
 	 */
 	private void handleLockStatus(LockStatus status) {
 		if (status != null) {
 			switch (status) {
 			case LOCKED_BY_ME:
 				AbstractEEFWidgetLifecycleManager.this.lockedByMe();
 				break;
 			case LOCKED_BY_OTHER:
 				AbstractEEFWidgetLifecycleManager.this.lockedByOther();
 				break;
 			case LOCKED_PERMISSION:
 				AbstractEEFWidgetLifecycleManager.this.lockedNoWrite();
 				break;
 			case UNLOCKED:
 				AbstractEEFWidgetLifecycleManager.this.unlocked();
 				break;
 			default:
 				AbstractEEFWidgetLifecycleManager.this.unlocked();
 				break;
 			}
 		}
 	}

 	/**
 	 * Returns the semantic element of the current widget.
 	 *
 	 * @return The semantic element of the current widget
 	 */
 	protected Object getWidgetSemanticElement() {
 		return this.variableManager.getVariables().get(EEFExpressionUtils.SELF);
 	}

 	/**
 	 * Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
 	 * is currently locked by the current user. By default, it will only display a small green lock next to the
 	 * validation control.
 	 */
 	protected void lockedByMe() {
 		if (this.controlDecoration.getControl() != null) {
 			this.controlDecoration.hide();
 			this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedByMe);
 			this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_GRANTED_TO_CURRENT_USER_EXCLUSIVELY));
 			this.controlDecoration.show();
 		}
 	}

 	/**
 	 * Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
 	 * is currently locked by another user. As a result, it will set the user interface in a disabled mode along with a
 	 * red lock next to the widget.
 	 */
 	protected void lockedByOther() {
 		this.setEnabled(false);

 		if (this.controlDecoration.getControl() != null) {
 			this.controlDecoration.hide();
 			this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedByOther);
 			this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_DENIED));
 			this.controlDecoration.show();
 		}
 	}

 	/**
 	 * Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
 	 * cannot be modified by the user. As a result, it will set the user interface in a disable mode with a grey lock
 	 * next to the widget.
 	 */
 	protected void lockedNoWrite() {
 		this.setEnabled(false);

 		if (this.controlDecoration.getControl() != null) {
 			this.controlDecoration.hide();
 			this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedNoWrite);
 			this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_NO_WRITE));
 			this.controlDecoration.show();
 		}
 	}

 	/**
 	 * Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
 	 * is currently unlocked. As a result, it will set back the widget to its default state.
 	 */
 	protected void unlocked() {
 		this.setEnabled(this.isEnabled());

 		if (this.controlDecoration.getControl() != null) {
 			this.controlDecoration.hide();
 		}
 	}

 	/**
 	 * Sets the enablement of the widget.
 	 *
 	 * @param isEnabled
 	 *            <code>true</code> when the widget should have its default behavior, <code>false</code> when the widget
 	 *            should be in a read only mode.
 	 */
 	protected abstract void setEnabled(boolean isEnabled);

 	/**
 	 * Check if a widget is enabled.
 	 *
 	 * @return True if the widget should be enabled otherwise false.
 	 */
 	protected boolean isEnabled() {
 		Boolean result = EvalFactory.of(interpreter, variableManager).logIfInvalidType(Boolean.class).defaultValue(Boolean.TRUE)
 				.evaluate(getWidgetDescription().getIsEnabledExpression());
 		return result.booleanValue();
 	}

 	/**
 	 * Set label font style.
 	 */
 	protected void setLabelFontStyle() {
 		EEFStyleHelper styleHelper = this.getEEFStyleHelper();
 		EEFWidgetStyle style = styleHelper.getWidgetStyle(getWidgetDescription());
 		IEEFTextStyleCallback callback = new EEFStyledTextStyleCallback(this.label);
 		if (style != null) {
 			styleHelper.applyTextStyle(style.getLabelFontNameExpression(), style.getLabelFontSizeExpression(), style.getLabelFontStyleExpression(),
 					this.label.getFont(), style.getLabelBackgroundColorExpression(), style.getLabelForegroundColorExpression(), callback);
 		} else {
 			// Set everything back to the default value
 			callback.applyForegroundColor(new EEFColor((Color) null));
 			callback.applyBackgroundColor(new EEFColor((Color) null));
 			callback.applyFontStyle(false, false);
 			callback.applyFont(new EEFFont(null, 0, 0) {
 				@Override
 				public Font getFont() {
 					return null;
 				}
 			});
 		}
 	}

 	/**
 	 * Returns the style helper used to compute the style of the widget.
 	 *
 	 * @return The style helper
 	 */
 	protected EEFStyleHelper getEEFStyleHelper() {
 		return new EEFStyleHelper(interpreter, variableManager);
 	}

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#refresh()
 	 */
 	@Override
 	public void refresh() {
 		super.refresh();

 		this.checkLockStatus();
 	}

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#aboutToBeHidden()
 	 */
 	@Override
 	public void aboutToBeHidden() {
 		super.aboutToBeHidden();
 		if (this.help != null && !this.help.isDisposed()) {
 			this.help.removeMouseTrackListener(mouseTrackListener);
 		}

 		this.getController().removeNewLabelConsumer();
 		this.editingContextAdapter.removeLockStatusChangedListener(this.lockStatusChangedListener);
 	}

 	/**
 	 * {@inheritDoc}
 	 *
 	 * @see org.eclipse.eef.ide.ui.api.widgets.IEEFLifecycleManager#dispose()
 	 */
 	@Override
 	public void dispose() {
 		EEFIdeUiPlugin.getPlugin().debug("AbstractEEFWidgetLifeCycleManager#dispose()"); //$NON-NLS-1$
 	}

 	/**
 	 * Returns the <code>IStructuredSelection</code> of the specified viewer.
 	 * <p>
 	 * Backport of <code>StructuredViewer.getStructuredSelection()</code> which was introduced in JFace 3.11 (Mars) to
 	 * work with JFace 3.10 (Luna).
 	 * </p>
 	 *
 	 * @param viewer
 	 *            the viewer.
 	 * @return IStructuredSelection
 	 * @throws ClassCastException
 	 *             if the selection of the viewer is not an instance of IStructuredSelection
 	 */
 	protected IStructuredSelection getStructuredSelection(StructuredViewer viewer) throws ClassCastException {
 		ISelection selection = viewer.getSelection();
 		if (selection instanceof IStructuredSelection) {
 			return (IStructuredSelection) selection;
 		}
 		throw new ClassCastException(Messages.AbstractEEFWidgetLifecycleManager_invalidSelectionType);
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2016, 2018 Obeo.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors: Obeo - initial API and implementation
	*******************************************************************************/
	package org.eclipse.eef.ide.ui.api.widgets;

	import java.util.Collection;
	import java.util.Optional;
	import java.util.function.Consumer;

	import org.eclipse.eef.EEFDynamicMappingFor;
	import org.eclipse.eef.EEFDynamicMappingIf;
	import org.eclipse.eef.EEFGroupDescription;
	import org.eclipse.eef.EEFWidgetDescription;
	import org.eclipse.eef.EEFWidgetStyle;
	import org.eclipse.eef.common.api.utils.Util;
	import org.eclipse.eef.common.ui.api.EEFWidgetFactory;
	import org.eclipse.eef.common.ui.api.IEEFFormContainer;
	import org.eclipse.eef.core.api.EEFExpressionUtils;
	import org.eclipse.eef.core.api.EditingContextAdapter;
	import org.eclipse.eef.core.api.LockStatusChangeEvent;
	import org.eclipse.eef.core.api.LockStatusChangeEvent.LockStatus;
	import org.eclipse.eef.core.api.controllers.IEEFWidgetController;
	import org.eclipse.eef.core.api.utils.EvalFactory;
	import org.eclipse.eef.ide.ui.api.widgets.EEFStyleHelper.IEEFTextStyleCallback;
	import org.eclipse.eef.ide.ui.internal.EEFIdeUiPlugin;
	import org.eclipse.eef.ide.ui.internal.Icons;
	import org.eclipse.eef.ide.ui.internal.Messages;
	import org.eclipse.eef.ide.ui.internal.widgets.EEFStyledTextStyleCallback;
	import org.eclipse.eef.ide.ui.internal.widgets.styles.EEFColor;
	import org.eclipse.eef.ide.ui.internal.widgets.styles.EEFFont;
	import org.eclipse.emf.ecore.EObject;
	import org.eclipse.jface.fieldassist.ControlDecoration;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.jface.viewers.StructuredViewer;
	import org.eclipse.sirius.common.interpreter.api.IInterpreter;
	import org.eclipse.sirius.common.interpreter.api.IVariableManager;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.CLabel;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.events.MouseEvent;
	import org.eclipse.swt.events.MouseTrackListener;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.Font;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Display;

	/**
	* Parent of all the lifecycle managers.
	*
	* @author sbegaudeau
	*/
	public abstract class AbstractEEFWidgetLifecycleManager extends AbstractEEFLifecycleManager {
	/**
	* The number of pixel of the additional gap necessary to draw the validation marker.
	*/
	protected static final int VALIDATION_MARKER_OFFSET = 5;

	/**
	* The variable manager.
	*/
	protected IVariableManager variableManager;

	/**
	* The interpreter.
	*/
	protected IInterpreter interpreter;

	/**
	* The editing context adapter.
	*/
	protected EditingContextAdapter editingContextAdapter;

	/**
	* The label.
	*/
	protected StyledText label;

	/**
	* The help label.
	*/
	protected CLabel help;

	/**
	* The listener on the help.
	*/
	private MouseTrackListener mouseTrackListener;

	/**
	* The listener used to react to changes in the lock status of a semantic element.
	*/
	private Consumer<Collection<LockStatusChangeEvent>> lockStatusChangedListener;

	/**
	* The decorator used to indicate the permission on the validation widget.
	*/
	private ControlDecoration controlDecoration;

	/**
	* The constructor.
	*
	* @param variableManager
	* The variable manager
	* @param interpreter
	* The interpreter
	* @param editingContextAdapter
	* The editing context adapter
	*/
	public AbstractEEFWidgetLifecycleManager(IVariableManager variableManager, IInterpreter interpreter,
	EditingContextAdapter editingContextAdapter) {
	this.variableManager = variableManager;
	this.interpreter = interpreter;
	this.editingContextAdapter = editingContextAdapter;
	}

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#createControl(org.eclipse.swt.widgets.Composite,
	* org.eclipse.eef.common.ui.api.IEEFFormContainer)
	*/
	@Override
	public void createControl(Composite parent, IEEFFormContainer formContainer) {
	super.createControl(parent, formContainer);

	EEFWidgetFactory widgetFactory = formContainer.getWidgetFactory();

	Composite composite = parent;

	// If we are in a group, we will always create a label (empty or not) for the 3 columns layout of the group.
	boolean isInGroup = this.isInGroup();

	// Some widgets (like a checkbox) will not have a separated "label" widget for their label. Those widgets will
	// thus never create another widget expect in the group (for the layout).
	boolean needsSeparatedLabel = this.needSeparatedLabel();

	// Finally if the label expression is blank, we will not create a label inside of a group (for the layout).
	boolean isBlankLabel = Util.isBlank(this.getWidgetDescription().getLabelExpression());

	boolean needsLabel = isInGroup \|\| (!isBlankLabel && needsSeparatedLabel);
	boolean needsHelp = isInGroup \|\| !Util.isBlank(this.getWidgetDescription().getHelpExpression());

	// If we are not in a group, we will create a composite to hold all the label and help of the widget if
	// necessary
	if (!isInGroup && (needsLabel \|\| needsHelp)) {
	composite = widgetFactory.createComposite(parent);

	// We will only create the necessary number of columns for this "invisible" composite
	int numColumn = 1;
	if (needsLabel) {
	numColumn = numColumn + 1;
	}
	if (needsHelp) {
	numColumn = numColumn + 1;
	}
	GridLayout layout = new GridLayout(numColumn, false);
	// As this composite is "invisible", it must not add border.
	layout.marginHeight = 0;
	layout.marginWidth = 0;
	composite.setLayout(layout);

	GridData layoutData = new GridData(GridData.FILL_HORIZONTAL);
	layoutData.horizontalSpan = 1;
	composite.setLayoutData(layoutData);
	}

	if (needsLabel) {
	this.label = widgetFactory.createStyledText(composite, SWT.READ_ONLY);
	this.label.setEditable(false);
	this.label.setCaret(null);
	this.label.setCursor(Display.getCurrent().getSystemCursor(SWT.CURSOR_ARROW));
	this.label.setDoubleClickEnabled(false);
	this.label.setLayoutData(new GridData(this.getLabelVerticalAlignment()));
	}

	if (needsHelp) {
	this.help = widgetFactory.createCLabel(composite, ""); //$NON-NLS-1$
	if (!Util.isBlank(this.getWidgetDescription().getHelpExpression())) {
	this.help.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.HELP));
	this.help.setLayoutData(new GridData(this.getLabelVerticalAlignment()));
	this.help.setToolTipText(""); //$NON-NLS-1$
	}
	}

	this.createMainControl(composite, formContainer);

	this.controlDecoration = new ControlDecoration(this.getValidationControl(), SWT.TOP \| SWT.LEFT);
	this.checkLockStatus();
	}

	/**
	* Checks the current lock status and make the user interface react to it.
	*/
	private void checkLockStatus() {
	Object self = this.variableManager.getVariables().get(EEFExpressionUtils.SELF);
	if (self instanceof EObject) {
	LockStatus status = this.editingContextAdapter.getLockStatus((EObject) self);
	this.handleLockStatus(status);
	}
	}

	/**
	* Indicates if the widget description is located directly under a group or if it is under a container.
	*
	* @return <code>true</code> if the widget description is directly under a group, <code>false</code> otherwise
	*/
	private boolean isInGroup() {
	EObject eContainer = this.getWidgetDescription().eContainer();

	// Test if the widget description is in a dynamic mapping directly under a group
	if (eContainer instanceof EEFDynamicMappingIf && eContainer.eContainer() instanceof EEFDynamicMappingFor) {
	EEFDynamicMappingFor dynamicMappingFor = (EEFDynamicMappingFor) eContainer.eContainer();
	return dynamicMappingFor.eContainer() instanceof EEFGroupDescription;
	}

	// Otherwise, let's test if it is directly under a group
	return eContainer instanceof EEFGroupDescription;
	}

	/**
	* Indicates if the widget should create a label widget for its label.
	*
	* @return <code>true</code> if a label should be created, <code>false</code> otherwise.
	*/
	protected boolean needSeparatedLabel() {
	return true;
	}

	/**
	* Returns the vertical alignment of the label of the widget. Use one of the following values:
	* <ul>
	* <li>GridData.VERTICAL_ALIGN_BEGINNING</li>
	* <li>GridData.VERTICAL_ALIGN_CENTER</li>
	* <li>GridData.VERTICAL_ALIGN_END</li>
	* </ul>
	*
	* @return The vertical alignment of the label of the widget
	*/
	protected int getLabelVerticalAlignment() {
	// By default, the label is aligned to the top of the widget
	return GridData.VERTICAL_ALIGN_BEGINNING;
	}

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#getController()
	*/
	@Override
	protected abstract IEEFWidgetController getController();

	/**
	* Returns the description of the widget.
	*
	* @return The description of the widget
	*/
	protected abstract EEFWidgetDescription getWidgetDescription();

	/**
	* Create the main control.
	*
	* @param parent
	* The composite parent
	* @param formContainer
	* The form container
	*/
	protected abstract void createMainControl(Composite parent, IEEFFormContainer formContainer);

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#aboutToBeShown()
	*/
	@Override
	public void aboutToBeShown() {
	super.aboutToBeShown();

	this.getController().onNewLabel((value) -> {
	if (!label.isDisposed() && !(label.getText() != null && label.getText().equals(value))) {
	label.setText(Optional.ofNullable(value).orElse("")); //$NON-NLS-1$
	}
	AbstractEEFWidgetLifecycleManager.this.setLabelFontStyle();
	});

	this.getController().onNewHelp((value) -> {
	if (help != null && !help.isDisposed() && !(help.getText() != null && help.getText().equals(value))) {
	help.setToolTipText(Optional.ofNullable(value).orElse(Messages.AbstractEEFWidgetLifecycleManager_noDescriptionAvailable));
	}
	});

	if (this.help != null) {
	this.mouseTrackListener = new MouseTrackListener() {

	@Override
	public void mouseHover(MouseEvent e) {
	// Defer the computation of the help message when the user hovers the Help label
	getController().computeHelp();
	}

	@Override
	public void mouseExit(MouseEvent e) {
	// Nothing todo
	}

	@Override
	public void mouseEnter(MouseEvent e) {
	// Nothing todo
	}
	};
	this.help.addMouseTrackListener(mouseTrackListener);
	}

	this.lockStatusChangedListener = (events) -> {
	Display.getDefault().asyncExec(() -> {
	events.stream().filter(event -> this.getWidgetSemanticElement().equals(event.getElement()))
	.forEach(event -> this.handleLockStatus(event.getStatus()));
	});
	};
	this.editingContextAdapter.addLockStatusChangedListener(this.lockStatusChangedListener);
	}

	/**
	* Handles the change in the lock status by switching the user interface to a "locked by me", "locked by other" or
	* "unlocked" state.
	*
	* @param status
	* The lock status
	*/
	private void handleLockStatus(LockStatus status) {
	if (status != null) {
	switch (status) {
	case LOCKED_BY_ME:
	AbstractEEFWidgetLifecycleManager.this.lockedByMe();
	break;
	case LOCKED_BY_OTHER:
	AbstractEEFWidgetLifecycleManager.this.lockedByOther();
	break;
	case LOCKED_PERMISSION:
	AbstractEEFWidgetLifecycleManager.this.lockedNoWrite();
	break;
	case UNLOCKED:
	AbstractEEFWidgetLifecycleManager.this.unlocked();
	break;
	default:
	AbstractEEFWidgetLifecycleManager.this.unlocked();
	break;
	}
	}
	}

	/**
	* Returns the semantic element of the current widget.
	*
	* @return The semantic element of the current widget
	*/
	protected Object getWidgetSemanticElement() {
	return this.variableManager.getVariables().get(EEFExpressionUtils.SELF);
	}

	/**
	* Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
	* is currently locked by the current user. By default, it will only display a small green lock next to the
	* validation control.
	*/
	protected void lockedByMe() {
	if (this.controlDecoration.getControl() != null) {
	this.controlDecoration.hide();
	this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedByMe);
	this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_GRANTED_TO_CURRENT_USER_EXCLUSIVELY));
	this.controlDecoration.show();
	}
	}

	/**
	* Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
	* is currently locked by another user. As a result, it will set the user interface in a disabled mode along with a
	* red lock next to the widget.
	*/
	protected void lockedByOther() {
	this.setEnabled(false);

	if (this.controlDecoration.getControl() != null) {
	this.controlDecoration.hide();
	this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedByOther);
	this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_DENIED));
	this.controlDecoration.show();
	}
	}

	/**
	* Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
	* cannot be modified by the user. As a result, it will set the user interface in a disable mode with a grey lock
	* next to the widget.
	*/
	protected void lockedNoWrite() {
	this.setEnabled(false);

	if (this.controlDecoration.getControl() != null) {
	this.controlDecoration.hide();
	this.controlDecoration.setDescriptionText(Messages.AbstractEEFWidgetLifecycleManager_lockedNoWrite);
	this.controlDecoration.setImage(EEFIdeUiPlugin.getPlugin().getImageRegistry().get(Icons.PERMISSION_NO_WRITE));
	this.controlDecoration.show();
	}
	}

	/**
	* Sets the appearance and behavior of the widget in order to indicate that the semantic element used by the widget
	* is currently unlocked. As a result, it will set back the widget to its default state.
	*/
	protected void unlocked() {
	this.setEnabled(this.isEnabled());

	if (this.controlDecoration.getControl() != null) {
	this.controlDecoration.hide();
	}
	}

	/**
	* Sets the enablement of the widget.
	*
	* @param isEnabled
	* <code>true</code> when the widget should have its default behavior, <code>false</code> when the widget
	* should be in a read only mode.
	*/
	protected abstract void setEnabled(boolean isEnabled);

	/**
	* Check if a widget is enabled.
	*
	* @return True if the widget should be enabled otherwise false.
	*/
	protected boolean isEnabled() {
	Boolean result = EvalFactory.of(interpreter, variableManager).logIfInvalidType(Boolean.class).defaultValue(Boolean.TRUE)
	.evaluate(getWidgetDescription().getIsEnabledExpression());
	return result.booleanValue();
	}

	/**
	* Set label font style.
	*/
	protected void setLabelFontStyle() {
	EEFStyleHelper styleHelper = this.getEEFStyleHelper();
	EEFWidgetStyle style = styleHelper.getWidgetStyle(getWidgetDescription());
	IEEFTextStyleCallback callback = new EEFStyledTextStyleCallback(this.label);
	if (style != null) {
	styleHelper.applyTextStyle(style.getLabelFontNameExpression(), style.getLabelFontSizeExpression(), style.getLabelFontStyleExpression(),
	this.label.getFont(), style.getLabelBackgroundColorExpression(), style.getLabelForegroundColorExpression(), callback);
	} else {
	// Set everything back to the default value
	callback.applyForegroundColor(new EEFColor((Color) null));
	callback.applyBackgroundColor(new EEFColor((Color) null));
	callback.applyFontStyle(false, false);
	callback.applyFont(new EEFFont(null, 0, 0) {
	@Override
	public Font getFont() {
	return null;
	}
	});
	}
	}

	/**
	* Returns the style helper used to compute the style of the widget.
	*
	* @return The style helper
	*/
	protected EEFStyleHelper getEEFStyleHelper() {
	return new EEFStyleHelper(interpreter, variableManager);
	}

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#refresh()
	*/
	@Override
	public void refresh() {
	super.refresh();

	this.checkLockStatus();
	}

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.AbstractEEFLifecycleManager#aboutToBeHidden()
	*/
	@Override
	public void aboutToBeHidden() {
	super.aboutToBeHidden();
	if (this.help != null && !this.help.isDisposed()) {
	this.help.removeMouseTrackListener(mouseTrackListener);
	}

	this.getController().removeNewLabelConsumer();
	this.editingContextAdapter.removeLockStatusChangedListener(this.lockStatusChangedListener);
	}

	/**
	* {@inheritDoc}
	*
	* @see org.eclipse.eef.ide.ui.api.widgets.IEEFLifecycleManager#dispose()
	*/
	@Override
	public void dispose() {
	EEFIdeUiPlugin.getPlugin().debug("AbstractEEFWidgetLifeCycleManager#dispose()"); //$NON-NLS-1$
	}

	/**
	* Returns the <code>IStructuredSelection</code> of the specified viewer.
	* <p>
	* Backport of <code>StructuredViewer.getStructuredSelection()</code> which was introduced in JFace 3.11 (Mars) to
	* work with JFace 3.10 (Luna).
	* </p>
	*
	* @param viewer
	* the viewer.
	* @return IStructuredSelection
	* @throws ClassCastException
	* if the selection of the viewer is not an instance of IStructuredSelection
	*/
	protected IStructuredSelection getStructuredSelection(StructuredViewer viewer) throws ClassCastException {
	ISelection selection = viewer.getSelection();
	if (selection instanceof IStructuredSelection) {
	return (IStructuredSelection) selection;
	}
	throw new ClassCastException(Messages.AbstractEEFWidgetLifecycleManager_invalidSelectionType);
	}

	}