Java tutorial
/****************************************************************************** * Copyright (c) 2011-2013, Linagora * * 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: * Linagora - initial API and implementation *******************************************************************************/ package com.ebmwebsourcing.petals.common.internal.provisional.emf; import java.util.ArrayList; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import org.eclipse.core.databinding.Binding; import org.eclipse.core.databinding.DataBindingContext; import org.eclipse.core.databinding.UpdateValueStrategy; import org.eclipse.core.databinding.observable.value.IObservableValue; import org.eclipse.core.databinding.validation.IValidator; import org.eclipse.core.databinding.validation.ValidationStatus; import org.eclipse.core.runtime.IStatus; import org.eclipse.emf.common.command.Command; import org.eclipse.emf.databinding.EMFObservables; import org.eclipse.emf.databinding.edit.EditingDomainEObjectObservableValue; import org.eclipse.emf.ecore.EAttribute; import org.eclipse.emf.ecore.EObject; import org.eclipse.emf.ecore.EStructuralFeature; import org.eclipse.emf.edit.command.AbstractOverrideableCommand; import org.eclipse.emf.edit.domain.EditingDomain; import org.eclipse.jface.databinding.fieldassist.ControlDecorationSupport; import org.eclipse.jface.databinding.swt.SWTObservables; import org.eclipse.jface.databinding.viewers.ViewersObservables; import org.eclipse.jface.layout.GridDataFactory; import org.eclipse.jface.viewers.ArrayContentProvider; import org.eclipse.jface.viewers.ComboViewer; import org.eclipse.jface.viewers.ISelectionProvider; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.osgi.util.NLS; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.StyledText; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Spinner; import org.eclipse.swt.widgets.Text; import org.eclipse.ui.forms.widgets.FormToolkit; import com.ebmwebsourcing.petals.common.internal.Messages; import com.ebmwebsourcing.petals.common.internal.provisional.utils.StringUtils; import com.ebmwebsourcing.petals.common.internal.provisional.utils.SwtFactory; /** * @author Mickael Istria - EBM WebSourcing */ public final class EObjectUIHelper { /** * Private constructor for utility class. */ private EObjectUIHelper() { // nothing } /** * A validator for mandatory fields. */ private static final class MandatoryFieldValidator implements IValidator { private final EStructuralFeature feature; /** * Constructor. * @param feature */ public MandatoryFieldValidator(EStructuralFeature feature) { this.feature = feature; } /* * (non-Javadoc) * @see org.eclipse.core.databinding.validation.IValidator * #validate(java.lang.Object) */ @Override public IStatus validate(Object value) { IStatus result = ValidationStatus.ok(); if (value instanceof String && StringUtils.isEmpty((String) value)) { String label = StringUtils.camelCaseToHuman(this.feature.getName()); label = StringUtils.capitalize(label); result = ValidationStatus.error(NLS.bind(Messages.fieldNotSet, label)); } return result; } } /** * An entry description. */ public static class EntryDescription { public Object widget; public EAttribute attribute; /** * Constructor. * @param widget * @param att */ public EntryDescription(Object widget, EAttribute att) { this.widget = widget; this.attribute = att; } } /** * Generates a 2 column list with left column containing description of widgets and right column containing widget. * @param eObject the eObject to edit * @param toolkit a {@link FormToolkit} to create widgets * @param parent * @param domain the {@link EditingDomain} in case of transactional edition. Can be null, then no transaction is used. * @param dbc * @param toProcessFeatures list of features to edit. * @return */ public static List<EntryDescription> generateWidgets(EObject eObject, FormToolkit toolkit, Composite parent, EditingDomain domain, DataBindingContext dbc, boolean showDecorator, EStructuralFeature... toProcessFeatures) { return generateWidgets(eObject, toolkit, null, parent, domain, dbc, showDecorator, toProcessFeatures); } /** * Generates a 2 column list with left column containing description of widgets and right column containing widget. * @param eObject the eObject to edit * @param toolkit a {@link FormToolkit} to create widgets * @param parent * @param domain the {@link EditingDomain} in case of transactional edition. Can be null, then no transaction is used. * @param dbc * @param toProcessFeatures list of features to edit. * @return */ public static List<EntryDescription> generateEditorWidgets(EObject eObject, FormToolkit toolkit, Composite parent, EditingDomain domain, DataBindingContext dbc, boolean showDecorator, EStructuralFeature... toProcessFeatures) { return generateWidgets(eObject, toolkit, parent.getDisplay().getSystemColor(SWT.COLOR_DARK_BLUE), parent, domain, dbc, showDecorator, toProcessFeatures); } /** * Generates a 2 column list with left column containing description of widgets and right column containing widget. * @param eObject the eObject to edit * @param toolkit a {@link FormToolkit} to create widgets * @param labelColor the foreground color for the label * @param parent * @param domain the {@link EditingDomain} in case of transactional edition. Can be null, then no transaction is used. * @param dbc * @param toProcessFeatures list of features to edit. * @return */ public static List<EntryDescription> generateWidgets(EObject eObject, FormToolkit toolkit, Color labelColor, Composite parent, EditingDomain domain, DataBindingContext dbc, boolean showDecorator, EStructuralFeature... toProcessFeatures) { Map<EStructuralFeature, String> map = new LinkedHashMap<EStructuralFeature, String>(); for (EStructuralFeature feature : toProcessFeatures) map.put(feature, null); List<EntryDescription> entries = produceWidgets(toolkit, labelColor, parent, map); setUpDatabinding(eObject, domain, dbc, showDecorator, entries); return entries; } /** * Generates a 2 column list with left column containing description of widgets and right column containing widget. * @param eObject the eObject to edit * @param toolkit a {@link FormToolkit} to create widgets * @param labelColor the foreground color for the label * @param parent * @param domain the {@link EditingDomain} in case of transactional edition. Can be null, then no transaction is used. * @param dbc * @param toProcessFeatures list of features to edit. * @return */ public static List<EntryDescription> generateWidget(EObject eObject, FormToolkit toolkit, Composite parent, EditingDomain domain, DataBindingContext dbc, boolean showDecorator, EStructuralFeature feature, String labelText) { Map<EStructuralFeature, String> map = new LinkedHashMap<EStructuralFeature, String>(); map.put(feature, labelText); Color labelColor = parent.getDisplay().getSystemColor(SWT.COLOR_DARK_BLUE); List<EntryDescription> entries = produceWidgets(toolkit, labelColor, parent, map); setUpDatabinding(eObject, domain, dbc, showDecorator, entries); return entries; } /** * Sets up the data binding. * @param eObject * @param domain * @param dbc * @param entries */ private static void setUpDatabinding(EObject eObject, EditingDomain domain, DataBindingContext dbc, boolean showDecorator, List<EntryDescription> entries) { for (EntryDescription entry : entries) { IObservableValue widgetObservable = null; if (entry.widget instanceof Text) widgetObservable = SWTObservables.observeDelayedValue(300, SWTObservables.observeText((Text) entry.widget, SWT.Modify)); else if (entry.widget instanceof StyledText) widgetObservable = SWTObservables.observeDelayedValue(300, SWTObservables.observeText((StyledText) entry.widget, SWT.Modify)); else if (entry.widget instanceof Spinner) widgetObservable = SWTObservables.observeSelection((Spinner) entry.widget); else if (entry.widget instanceof ISelectionProvider) widgetObservable = ViewersObservables.observeSingleSelection((ISelectionProvider) entry.widget); else if (entry.widget instanceof Button) widgetObservable = SWTObservables.observeSelection((Button) entry.widget); if (widgetObservable != null) { UpdateValueStrategy targetToModel = new UpdateValueStrategy(); if (entry.attribute.getLowerBound() > 0) targetToModel.setBeforeSetValidator(new MandatoryFieldValidator(entry.attribute)); IObservableValue iov = domain == null ? EMFObservables.observeValue(eObject, entry.attribute) // : EMFEditObservables.observeValue( domain, eObject, entry.attribute ); : createCustomEmfEditObservable(domain, eObject, entry.attribute); Binding binding; if (domain == null) binding = dbc.bindValue(widgetObservable, iov, targetToModel, null); else binding = dbc.bindValue(widgetObservable, iov); if (showDecorator && entry.attribute.getLowerBound() > 0) ControlDecorationSupport.create(binding, SWT.TOP | SWT.LEFT); } } } /** * Creates an observable using an editing domain. * <p> * This method is a workaround for SetCommands (EMF version <2.7.1). * Keep it, even if it is not used. * </p> * * @param domain * @param eo * @param ea * @return an IObservable value * TODO: replace this method by EMFEditObservables as soon as EMF 2.8.0 or 2.7.2 is out * @See https://bugs.eclipse.org/bugs/show_bug.cgi?id=356291 * @See https://bugs.eclipse.org/bugs/show_bug.cgi?id=359043 */ public static IObservableValue createCustomEmfEditObservable(EditingDomain domain, final EObject eo, final EAttribute ea) { return new EditingDomainEObjectObservableValue(domain, eo, ea) { @Override protected void doSetValue(final Object value) { Command command = createCustomSetCommand(this.domain, eo, ea, value); this.domain.getCommandStack().execute(command); } }; } /** * Creates a custom set command to use with model extensions. * @param domain * @param eo * @param ea * @param value * @return a custom set command (with less checks) * TODO: replace this method by the real SetCommand as soon as EMF 2.8.0 or 2.7.2 is out * @See https://bugs.eclipse.org/bugs/show_bug.cgi?id=356291 * @See https://bugs.eclipse.org/bugs/show_bug.cgi?id=359043 */ public static Command createCustomSetCommand(final EditingDomain domain, final EObject eo, final EAttribute ea, final Object value) { return new AbstractOverrideableCommand(domain, "MySetCommand") { private Object oldValue; @Override public void doExecute() { this.oldValue = eo.eGet(ea); eo.eSet(ea, value); } @Override public void doUndo() { eo.eSet(ea, this.oldValue); } @Override public void doRedo() { execute(); } @Override public boolean doCanExecute() { return true; } }; } /** * Produces the widgets. * @param toolkit * @param parent * @param featuresToLabels * @return */ private static List<EntryDescription> produceWidgets(FormToolkit toolkit, Color labelColor, Composite parent, Map<EStructuralFeature, String> featuresToLabels) { List<EntryDescription> entries = new ArrayList<EntryDescription>(); for (Map.Entry<EStructuralFeature, String> entry : featuresToLabels.entrySet()) { Object widget = null; EAttribute attr = (EAttribute) entry.getKey(); String label = entry.getValue(); // The label // TODO leverage ExtendedMetaData.INSTANCE for tool tip and label if (label == null) { label = StringUtils.camelCaseToHuman(attr.getName()); label = StringUtils.capitalize(label); if (attr.getLowerBound() > 0) label += " *"; label += ":"; } Label labelWidget = toolkit.createLabel(parent, label); labelWidget.setBackground(parent.getBackground()); if (labelColor != null) labelWidget.setForeground(labelColor); // The widget Class<?> instanceClass = attr.getEType().getInstanceClass(); if (instanceClass.equals(String.class)) { String lowered = label.toLowerCase(); if (lowered.contains("password") || lowered.contains("passphrase")) widget = SwtFactory.createPasswordField(parent, false).getText(); else if (lowered.contains("folder") || lowered.contains("directory")) widget = SwtFactory.createDirectoryBrowser(parent).getText(); else widget = toolkit.createText(parent, "", SWT.BORDER); ((Text) widget).setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); } else if (instanceClass.equals(Integer.class) || instanceClass.equals(int.class)) { widget = new Spinner(parent, SWT.BORDER); GridDataFactory.swtDefaults().hint(100, SWT.DEFAULT).minSize(100, SWT.DEFAULT) .applyTo((Spinner) widget); ((Spinner) widget).setMaximum(Integer.MAX_VALUE); } else if (instanceClass.isEnum()) { widget = new ComboViewer(parent, SWT.READ_ONLY | SWT.FLAT); ComboViewer viewer = (ComboViewer) widget; viewer.setContentProvider(new EEnumLiteralsProvider()); viewer.setLabelProvider(new EEnumNameLabelProvider()); viewer.setInput(attr.getEType()); viewer.getCombo().setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); } else if (instanceClass.equals(Boolean.class) || instanceClass.equals(boolean.class)) { widget = new ComboViewer(parent, SWT.READ_ONLY | SWT.FLAT); ComboViewer viewer = (ComboViewer) widget; viewer.setContentProvider(new ArrayContentProvider()); viewer.setLabelProvider(new LabelProvider()); viewer.setInput(new Boolean[] { Boolean.TRUE, Boolean.FALSE }); Combo combo = ((ComboViewer) widget).getCombo(); GridDataFactory.swtDefaults().hint(100, SWT.DEFAULT).minSize(100, SWT.DEFAULT).applyTo(combo); } if (widget != null) entries.add(new EntryDescription(widget, attr)); } return entries; } }