Java tutorial
/* * Copyright (c) 2012 Data Harmonisation Panel * * All rights reserved. This program and the accompanying materials are made * available under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation, either version 3 of the License, * or (at your option) any later version. * * You should have received a copy of the GNU Lesser General Public License * along with this distribution. If not, see <http://www.gnu.org/licenses/>. * * Contributors: * HUMBOLDT EU Integrated Project #030962 * Data Harmonisation Panel <http://www.dhpanel.eu> */ package eu.esdihumboldt.hale.ui.util.wizard; import org.eclipse.jface.dialogs.Dialog; import org.eclipse.jface.dialogs.IDialogPage; import org.eclipse.jface.layout.GridDataFactory; import org.eclipse.jface.viewers.DoubleClickEvent; import org.eclipse.jface.viewers.IDoubleClickListener; import org.eclipse.jface.viewers.ISelection; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.StructuredViewer; import org.eclipse.jface.viewers.TreeViewer; import org.eclipse.jface.wizard.IWizardNode; import org.eclipse.jface.wizard.WizardSelectionPage; import org.eclipse.swt.SWT; import org.eclipse.swt.graphics.Font; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import eu.esdihumboldt.util.Pair; /** * Wizard selection page based on a structured viewer. * * @author Simon Templer */ public abstract class ViewerWizardSelectionPage extends WizardSelectionPage { private StructuredViewer viewer; /** * @see WizardSelectionPage#WizardSelectionPage(String) */ protected ViewerWizardSelectionPage(String pageName) { super(pageName); } /** * Get the size hint for the viewer height. * * @return the size hint */ protected int getViewerHeightHint() { return SWT.DEFAULT; } /** * @see IDialogPage#createControl(Composite) */ @Override public void createControl(Composite parent) { Font font = parent.getFont(); // create composite for page. Composite outerContainer = new Composite(parent, SWT.NONE); outerContainer.setLayout(new GridLayout()); outerContainer.setLayoutData(GridDataFactory.fillDefaults().grab(true, true).create()); outerContainer.setFont(font); Pair<StructuredViewer, Control> viewerControl = createViewer(outerContainer); viewer = viewerControl.getFirst(); viewerControl.getSecond().setLayoutData( GridDataFactory.fillDefaults().grab(true, true).hint(SWT.DEFAULT, getViewerHeightHint()).create()); // wire viewer viewer.addSelectionChangedListener(new ISelectionChangedListener() { @Override public void selectionChanged(SelectionChangedEvent event) { viewerSelectionChanged(event.getSelection()); } }); viewer.addDoubleClickListener(new IDoubleClickListener() { @Override public void doubleClick(DoubleClickEvent event) { doubleClicked(event); } }); Dialog.applyDialogFont(outerContainer); // apply the initial selection viewerSelectionChanged(viewer.getSelection()); setControl(outerContainer); } /** * Called when the viewer selection has changed. * * @param selection the current selection */ protected void viewerSelectionChanged(ISelection selection) { setErrorMessage(null); IStructuredSelection ss = (IStructuredSelection) selection; Object sel = ss.getFirstElement(); if (sel instanceof IWizardNode) { IWizardNode currentWizardSelection = (IWizardNode) sel; updateSelectedNode(currentWizardSelection); } else { updateSelectedNode(null); } } /** * Update the selected node * * @param wizardNode the selected wizard node */ private void updateSelectedNode(IWizardNode wizardNode) { setErrorMessage(null); if (wizardNode == null) { updateMessage(); setSelectedNode(null); return; } // set the message based on the wizard description if (wizardNode instanceof ExtendedWizardNode) { setMessage(((ExtendedWizardNode) wizardNode).getDescription(), INFORMATION); } else { setMessage(null); } // set the selected node setSelectedNode(wizardNode); } /** * @see WizardSelectionPage#setSelectedNode(IWizardNode) */ @Override protected void setSelectedNode(IWizardNode node) { if (node != null) { String message = acceptWizard(node); if (message != null) { // display warning message setMessage(message, WARNING); // disable next super.setSelectedNode(null); return; } } super.setSelectedNode(node); } /** * Accepts or doesn't accept a wizard node as a valid selection. * * @param wizardNode the wizard node * @return <code>null</code> if the node is accepted or a reason why it is * not accepted. */ protected String acceptWizard(IWizardNode wizardNode) { return null; } /** * Update the selected node based on the viewer selection. */ protected void updateMessage() { if (viewer != null) { ISelection selection = viewer.getSelection(); IStructuredSelection ss = (IStructuredSelection) selection; Object sel = ss.getFirstElement(); if (sel instanceof IWizardNode) { updateSelectedNode((IWizardNode) sel); } else { setSelectedNode(null); } } else { setMessage(null); } } /** * Called when a double click in the viewer occurs. * * @param event the double click event */ protected void doubleClicked(DoubleClickEvent event) { ISelection selection = event.getViewer().getSelection(); IStructuredSelection ss = (IStructuredSelection) selection; viewerSelectionChanged(ss); Object element = ss.getFirstElement(); if (element instanceof IWizardNode) { if (canFlipToNextPage()) { getContainer().showPage(getNextPage()); return; } } else if (event.getViewer() instanceof TreeViewer) { TreeViewer viewer = (TreeViewer) event.getViewer(); viewer.setExpandedState(element, !viewer.getExpandedState(element)); } getContainer().showPage(getNextPage()); } /** * Create the structured viewer and set it up with label and content * providers as well as the input. The viewer must provide * {@link IStructuredSelection}s with {@link IWizardNode}s. * * @param parent the parent composite * @return the viewer paired with the main control that should fill the * parent composite */ protected abstract Pair<StructuredViewer, Control> createViewer(Composite parent); }