ui/org.eclipse.pde.ui/src/org/eclipse/pde/internal/ui/preferences/TargetPlatformPreferencePage2.java - pde/eclipse.pde.ui - Git at Google

 /*******************************************************************************
  * Copyright (c) 2009 EclipseSource 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:
  *     EclipseSource Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.pde.internal.ui.preferences;

 import java.util.*;
 import java.util.List;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.jobs.Job;
 import org.eclipse.jface.dialogs.Dialog;
 import org.eclipse.jface.dialogs.ErrorDialog;
 import org.eclipse.jface.preference.PreferencePage;
 import org.eclipse.jface.viewers.*;
 import org.eclipse.jface.window.Window;
 import org.eclipse.jface.wizard.WizardDialog;
 import org.eclipse.pde.internal.core.PDECore;
 import org.eclipse.pde.internal.core.PluginModelManager;
 import org.eclipse.pde.internal.core.target.impl.TargetDefinition;
 import org.eclipse.pde.internal.core.target.impl.TargetPlatformService;
 import org.eclipse.pde.internal.core.target.provisional.*;
 import org.eclipse.pde.internal.ui.*;
 import org.eclipse.pde.internal.ui.wizards.target.EditTargetDefinitionWizard;
 import org.eclipse.pde.internal.ui.wizards.target.NewTargetDefinitionWizard2;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.*;
 import org.eclipse.ui.*;

 public class TargetPlatformPreferencePage2 extends PreferencePage implements IWorkbenchPreferencePage {

 	private class TargetLabelProvider extends LabelProvider {
 		public Image getImage(Object element) {
 			return PDEPlugin.getDefault().getLabelProvider().get(PDEPluginImages.DESC_TARGET_DEFINITION);
 		}

 		public String getText(Object element) {
 			String name = ((ITargetDefinition) element).getName();
 			if (name == null || name.length() == 0) {
 				return ((ITargetDefinition) element).getHandle().toString();
 			}
 			return name;
 		}
 	}

 	// Table viewer
 	private CheckboxTableViewer fTableViewer = null;

 	// Buttons
 	private Button fAddButton = null;
 	private Button fEditButton = null;
 	//private Button fDuplicateButton = null;
 	private Button fRemoveButton = null;

 	// Initial collection of targets (handles are realized into definitions as working copies)
 	private List fTargets = new ArrayList();

 	// Removed definitions (to be removed on apply)
 	private List fRemoved = new ArrayList();

 	public TargetPlatformPreferencePage2() {
 		// nothing
 	}

 	public void dispose() {
 		super.dispose();
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite)
 	 */
 	public Control createContents(Composite parent) {
 		Composite container = new Composite(parent, SWT.NONE);
 		GridLayout layout = new GridLayout();
 		layout.marginHeight = layout.marginWidth = 0;
 		container.setLayout(layout);

 		createTargetProfilesGroup(container);

 		Dialog.applyDialogFont(container);
 		PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), IHelpContextIds.TARGET_PLATFORM_PREFERENCE_PAGE);
 		return container;
 	}

 	private void createTargetProfilesGroup(Composite container) {
 		Composite comp = SWTFactory.createComposite(container, 1, 1, GridData.FILL_BOTH, 0, 0);
 		SWTFactory.createWrapLabel(comp, PDEUIMessages.TargetPlatformPreferencePage2_0, 2, 250);
 		SWTFactory.createWrapLabel(comp, PDEUIMessages.TargetPlatformPreferencePage2_1, 2, 250);
 		SWTFactory.createVerticalSpacer(comp, 1);

 		Composite tableComposite = SWTFactory.createComposite(comp, 2, 1, GridData.FILL_BOTH, 0, 0);
 		SWTFactory.createWrapLabel(tableComposite, PDEUIMessages.TargetPlatformPreferencePage2_2, 2);
 		Table table = new Table(tableComposite, SWT.FULL_SELECTION | SWT.MULTI | SWT.BORDER | SWT.CHECK);
 		table.setLayoutData(new GridData(GridData.FILL_BOTH));
 		fTableViewer = new CheckboxTableViewer(table);
 		fTableViewer.setLabelProvider(new TargetLabelProvider());
 		fTableViewer.setContentProvider(ArrayContentProvider.getInstance());
 		fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() {
 			public void selectionChanged(SelectionChangedEvent event) {
 				updateButtons();
 			}
 		});
 		fTableViewer.setComparator(new ViewerComparator());

 		// add the targets
 		ITargetPlatformService service = getTargetService();
 		if (service != null) {
 			ITargetHandle[] targets = service.getTargets(null);
 			for (int i = 0; i < targets.length; i++) {
 				try {
 					fTargets.add(targets[i].getTargetDefinition());
 				} catch (CoreException e) {
 					setErrorMessage(e.getMessage());
 				}
 			}
 			fTableViewer.setInput(fTargets);
 		}

 		// Single check behavior
 		fTableViewer.addCheckStateListener(new ICheckStateListener() {
 			public void checkStateChanged(CheckStateChangedEvent event) {
 				if (event.getChecked()) {
 					fTableViewer.setCheckedElements(new Object[] {event.getElement()});
 				} else {
 					fTableViewer.setCheckedElements(new Object[0]);
 				}
 			}
 		});

 		Composite buttonComposite = SWTFactory.createComposite(tableComposite, 1, 1, GridData.FILL_VERTICAL | GridData.VERTICAL_ALIGN_BEGINNING, 0, 0);
 		fAddButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_3, null);
 		fAddButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				NewTargetDefinitionWizard2 wizard = new NewTargetDefinitionWizard2();
 				wizard.setWindowTitle(PDEUIMessages.TargetPlatformPreferencePage2_4);
 				WizardDialog dialog = new WizardDialog(fAddButton.getShell(), wizard);
 				if (dialog.open() == Window.OK) {
 					ITargetDefinition def = wizard.getTargetDefinition();
 					fTargets.add(def);
 					fTableViewer.refresh();
 					fTableViewer.setSelection(new StructuredSelection(def));
 				}
 			}
 		});

 		fEditButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_5, null);
 		fEditButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				ITargetDefinition def = (ITargetDefinition) ((IStructuredSelection) fTableViewer.getSelection()).getFirstElement();
 				EditTargetDefinitionWizard wizard = new EditTargetDefinitionWizard(def);
 				wizard.setWindowTitle(PDEUIMessages.TargetPlatformPreferencePage2_6);
 				WizardDialog dialog = new WizardDialog(fEditButton.getShell(), wizard);
 				if (dialog.open() == Window.OK) {
 					fTableViewer.refresh();
 				}
 			}
 		});

 		// TODO: post M5, implement "duplicate"
 //		fDuplicateButton = SWTFactory.createPushButton(buttonComposite, "Duplicate...", null);
 //		fDuplicateButton.addSelectionListener(new SelectionAdapter() {
 //			public void widgetSelected(SelectionEvent e) {
 //				// for now we always duplicate to local metadata
 //				IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
 //				ITargetDefinition source = (ITargetDefinition) selection.getFirstElement();
 //				ITargetPlatformService service = getTargetService();
 //				if (service != null) {
 //					ITargetDefinition dup = service.newTarget();
 //					try {
 //						service.copyTargetDefinition(source, dup);
 //						dup.setName(NLS.bind("Copy of {0}", source.getName()));
 //						fTargets.add(dup);
 //						fTableViewer.refresh();
 //						fTableViewer.setSelection(new StructuredSelection(dup));
 //					} catch (CoreException ex) {
 //						setErrorMessage(ex.getMessage());
 //					}
 //				}
 //			}
 //		});

 		fRemoveButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_7, null);
 		fRemoveButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
 				List selected = selection.toList();
 				fRemoved.addAll(selected);
 				fTargets.removeAll(selected);
 				fTableViewer.refresh();
 				// TODO: update selection
 			}
 		});

 		updateButtons();

 		if (service != null) {
 			try {
 				ITargetHandle handle = service.getWorkspaceTargetHandle();
 				Iterator iterator = fTargets.iterator();
 				while (iterator.hasNext()) {
 					ITargetDefinition target = (ITargetDefinition) iterator.next();
 					if (target.getHandle().equals(handle)) {
 						fTableViewer.setCheckedElements(new Object[] {target});
 						break;
 					}
 				}
 			} catch (CoreException e) {
 				setErrorMessage(e.getMessage());
 			}
 		}
 	}

 	/**
 	 * Update enabled state of buttons
 	 */
 	protected void updateButtons() {
 		// update enabled state of buttons
 		IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
 		int size = selection.size();
 		fRemoveButton.setEnabled(size > 0);
 		fEditButton.setEnabled(size == 1);
 		//fDuplicateButton.setEnabled(size == 1);
 	}

 	/**
 	 * Returns the target platform service.
 	 *
 	 * @return target platform service
 	 */
 	private ITargetPlatformService getTargetService() {
 		return (ITargetPlatformService) PDECore.getDefault().acquireService(ITargetPlatformService.class.getName());
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.ui.IWorkbenchPreferencePage#init(org.eclipse.ui.IWorkbench)
 	 */
 	public void init(IWorkbench workbench) {
 		// ensures default targets are created when page is opened (if not created yet)
 		PluginModelManager manager = PDECore.getDefault().getModelManager();
 		manager.getExternalModelManager();
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.PreferencePage#performDefaults()
 	 */
 	public void performDefaults() {
 		// add a default target platform and select it (or just select it if present)
 		ITargetPlatformService service = getTargetService();
 		if (service instanceof TargetPlatformService) {
 			TargetPlatformService ts = (TargetPlatformService) service;
 			ITargetDefinition deflt = ts.newDefaultTargetDefinition();
 			Iterator iterator = fTargets.iterator();
 			ITargetDefinition reuse = null;
 			while (iterator.hasNext()) {
 				TargetDefinition existing = (TargetDefinition) iterator.next();
 				if (existing.isContentEquivalent(deflt)) {
 					reuse = existing;
 					break;
 				}
 			}
 			if (reuse != null) {
 				deflt = reuse;
 			} else {
 				fTargets.add(deflt);
 			}
 			fTableViewer.refresh();
 			fTableViewer.setCheckedElements(new Object[] {deflt});
 		}
 		super.performDefaults();
 	}

 	/* (non-Javadoc)
 	 * @see org.eclipse.jface.preference.PreferencePage#performOk()
 	 */
 	public boolean performOk() {
 		ITargetPlatformService service = getTargetService();
 		if (service == null) {
 			return false;
 		}

 		// determine if default target has changed
 		ITargetDefinition toLoad = null;
 		boolean load = false;
 		try {
 			ITargetHandle prev = service.getWorkspaceTargetHandle();
 			ITargetHandle currH = null;
 			ITargetDefinition currD = null;
 			Object[] elements = fTableViewer.getCheckedElements();
 			if (elements.length > 0) {
 				currD = (ITargetDefinition) elements[0];
 				currH = currD.getHandle();
 			}
 			if (prev == null) {
 				if (currH != null) {
 					toLoad = currD;
 					load = true;
 				}
 			} else {
 				if (currH == null) {
 					// load empty
 					load = true;
 				} else if (!prev.equals(currH)) {
 					toLoad = currD;
 					load = true;
 				} else {
 					ITargetDefinition original = prev.getTargetDefinition();
 					// TODO: should just check for structural changes
 					if (((TargetDefinition) original).isContentEquivalent(currD)) {
 						load = false;
 					} else {
 						load = true;
 						toLoad = currD;
 					}
 				}
 			}
 		} catch (CoreException e) {
 			ErrorDialog.openError(getShell(), PDEUIMessages.TargetPlatformPreferencePage2_8, PDEUIMessages.TargetPlatformPreferencePage2_9, e.getStatus());
 			return false;
 		}

 		// Remove any definitions that have been removed
 		// TODO should we prompt? (only if workspace files?)
 		Iterator iterator = fRemoved.iterator();
 		while (iterator.hasNext()) {
 			ITargetDefinition target = (ITargetDefinition) iterator.next();
 			try {
 				service.deleteTarget(target.getHandle());
 			} catch (CoreException e) {
 				ErrorDialog.openError(getShell(), PDEUIMessages.TargetPlatformPreferencePage2_8, PDEUIMessages.TargetPlatformPreferencePage2_11, e.getStatus());
 				return false;
 			}
 		}
 		// save others that are dirty
 		iterator = fTargets.iterator();
 		while (iterator.hasNext()) {
 			ITargetDefinition def = (ITargetDefinition) iterator.next();
 			boolean save = true;
 			if (def.getHandle().exists()) {
 				try {
 					ITargetDefinition original = def.getHandle().getTargetDefinition();
 					if (((TargetDefinition) original).isContentEqual(def)) {
 						save = false;
 					}
 				} catch (CoreException e) {
 					// failed to generate original
 					setErrorMessage(e.getMessage());
 					return false;
 				}
 			}
 			if (save) {
 				try {
 					service.saveTargetDefinition(def);
 				} catch (CoreException e) {
 					setErrorMessage(e.getMessage());
 					return false;
 				}
 			}
 		}

 		// set workspace target if required
 		if (load) {
 			// TODO: prompt to warn of build? (like JRE page)
 			Job job = new LoadTargetDefinitionJob(toLoad);
 			job.schedule();
 		}

 		return super.performOk();
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2009 EclipseSource 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:
	* EclipseSource Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.pde.internal.ui.preferences;

	import java.util.*;
	import java.util.List;
	import org.eclipse.core.runtime.CoreException;
	import org.eclipse.core.runtime.jobs.Job;
	import org.eclipse.jface.dialogs.Dialog;
	import org.eclipse.jface.dialogs.ErrorDialog;
	import org.eclipse.jface.preference.PreferencePage;
	import org.eclipse.jface.viewers.*;
	import org.eclipse.jface.window.Window;
	import org.eclipse.jface.wizard.WizardDialog;
	import org.eclipse.pde.internal.core.PDECore;
	import org.eclipse.pde.internal.core.PluginModelManager;
	import org.eclipse.pde.internal.core.target.impl.TargetDefinition;
	import org.eclipse.pde.internal.core.target.impl.TargetPlatformService;
	import org.eclipse.pde.internal.core.target.provisional.*;
	import org.eclipse.pde.internal.ui.*;
	import org.eclipse.pde.internal.ui.wizards.target.EditTargetDefinitionWizard;
	import org.eclipse.pde.internal.ui.wizards.target.NewTargetDefinitionWizard2;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.*;
	import org.eclipse.ui.*;

	public class TargetPlatformPreferencePage2 extends PreferencePage implements IWorkbenchPreferencePage {

	private class TargetLabelProvider extends LabelProvider {
	public Image getImage(Object element) {
	return PDEPlugin.getDefault().getLabelProvider().get(PDEPluginImages.DESC_TARGET_DEFINITION);
	}

	public String getText(Object element) {
	String name = ((ITargetDefinition) element).getName();
	if (name == null \|\| name.length() == 0) {
	return ((ITargetDefinition) element).getHandle().toString();
	}
	return name;
	}
	}

	// Table viewer
	private CheckboxTableViewer fTableViewer = null;

	// Buttons
	private Button fAddButton = null;
	private Button fEditButton = null;
	//private Button fDuplicateButton = null;
	private Button fRemoveButton = null;

	// Initial collection of targets (handles are realized into definitions as working copies)
	private List fTargets = new ArrayList();

	// Removed definitions (to be removed on apply)
	private List fRemoved = new ArrayList();

	public TargetPlatformPreferencePage2() {
	// nothing
	}

	public void dispose() {
	super.dispose();
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite)
	*/
	public Control createContents(Composite parent) {
	Composite container = new Composite(parent, SWT.NONE);
	GridLayout layout = new GridLayout();
	layout.marginHeight = layout.marginWidth = 0;
	container.setLayout(layout);

	createTargetProfilesGroup(container);

	Dialog.applyDialogFont(container);
	PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(), IHelpContextIds.TARGET_PLATFORM_PREFERENCE_PAGE);
	return container;
	}

	private void createTargetProfilesGroup(Composite container) {
	Composite comp = SWTFactory.createComposite(container, 1, 1, GridData.FILL_BOTH, 0, 0);
	SWTFactory.createWrapLabel(comp, PDEUIMessages.TargetPlatformPreferencePage2_0, 2, 250);
	SWTFactory.createWrapLabel(comp, PDEUIMessages.TargetPlatformPreferencePage2_1, 2, 250);
	SWTFactory.createVerticalSpacer(comp, 1);

	Composite tableComposite = SWTFactory.createComposite(comp, 2, 1, GridData.FILL_BOTH, 0, 0);
	SWTFactory.createWrapLabel(tableComposite, PDEUIMessages.TargetPlatformPreferencePage2_2, 2);
	Table table = new Table(tableComposite, SWT.FULL_SELECTION \| SWT.MULTI \| SWT.BORDER \| SWT.CHECK);
	table.setLayoutData(new GridData(GridData.FILL_BOTH));
	fTableViewer = new CheckboxTableViewer(table);
	fTableViewer.setLabelProvider(new TargetLabelProvider());
	fTableViewer.setContentProvider(ArrayContentProvider.getInstance());
	fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() {
	public void selectionChanged(SelectionChangedEvent event) {
	updateButtons();
	}
	});
	fTableViewer.setComparator(new ViewerComparator());

	// add the targets
	ITargetPlatformService service = getTargetService();
	if (service != null) {
	ITargetHandle[] targets = service.getTargets(null);
	for (int i = 0; i < targets.length; i++) {
	try {
	fTargets.add(targets[i].getTargetDefinition());
	} catch (CoreException e) {
	setErrorMessage(e.getMessage());
	}
	}
	fTableViewer.setInput(fTargets);
	}

	// Single check behavior
	fTableViewer.addCheckStateListener(new ICheckStateListener() {
	public void checkStateChanged(CheckStateChangedEvent event) {
	if (event.getChecked()) {
	fTableViewer.setCheckedElements(new Object[] {event.getElement()});
	} else {
	fTableViewer.setCheckedElements(new Object[0]);
	}
	}
	});

	Composite buttonComposite = SWTFactory.createComposite(tableComposite, 1, 1, GridData.FILL_VERTICAL \| GridData.VERTICAL_ALIGN_BEGINNING, 0, 0);
	fAddButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_3, null);
	fAddButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	NewTargetDefinitionWizard2 wizard = new NewTargetDefinitionWizard2();
	wizard.setWindowTitle(PDEUIMessages.TargetPlatformPreferencePage2_4);
	WizardDialog dialog = new WizardDialog(fAddButton.getShell(), wizard);
	if (dialog.open() == Window.OK) {
	ITargetDefinition def = wizard.getTargetDefinition();
	fTargets.add(def);
	fTableViewer.refresh();
	fTableViewer.setSelection(new StructuredSelection(def));
	}
	}
	});

	fEditButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_5, null);
	fEditButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	ITargetDefinition def = (ITargetDefinition) ((IStructuredSelection) fTableViewer.getSelection()).getFirstElement();
	EditTargetDefinitionWizard wizard = new EditTargetDefinitionWizard(def);
	wizard.setWindowTitle(PDEUIMessages.TargetPlatformPreferencePage2_6);
	WizardDialog dialog = new WizardDialog(fEditButton.getShell(), wizard);
	if (dialog.open() == Window.OK) {
	fTableViewer.refresh();
	}
	}
	});

	// TODO: post M5, implement "duplicate"
	// fDuplicateButton = SWTFactory.createPushButton(buttonComposite, "Duplicate...", null);
	// fDuplicateButton.addSelectionListener(new SelectionAdapter() {
	// public void widgetSelected(SelectionEvent e) {
	// // for now we always duplicate to local metadata
	// IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
	// ITargetDefinition source = (ITargetDefinition) selection.getFirstElement();
	// ITargetPlatformService service = getTargetService();
	// if (service != null) {
	// ITargetDefinition dup = service.newTarget();
	// try {
	// service.copyTargetDefinition(source, dup);
	// dup.setName(NLS.bind("Copy of {0}", source.getName()));
	// fTargets.add(dup);
	// fTableViewer.refresh();
	// fTableViewer.setSelection(new StructuredSelection(dup));
	// } catch (CoreException ex) {
	// setErrorMessage(ex.getMessage());
	// }
	// }
	// }
	// });

	fRemoveButton = SWTFactory.createPushButton(buttonComposite, PDEUIMessages.TargetPlatformPreferencePage2_7, null);
	fRemoveButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
	List selected = selection.toList();
	fRemoved.addAll(selected);
	fTargets.removeAll(selected);
	fTableViewer.refresh();
	// TODO: update selection
	}
	});

	updateButtons();

	if (service != null) {
	try {
	ITargetHandle handle = service.getWorkspaceTargetHandle();
	Iterator iterator = fTargets.iterator();
	while (iterator.hasNext()) {
	ITargetDefinition target = (ITargetDefinition) iterator.next();
	if (target.getHandle().equals(handle)) {
	fTableViewer.setCheckedElements(new Object[] {target});
	break;
	}
	}
	} catch (CoreException e) {
	setErrorMessage(e.getMessage());
	}
	}
	}

	/**
	* Update enabled state of buttons
	*/
	protected void updateButtons() {
	// update enabled state of buttons
	IStructuredSelection selection = (IStructuredSelection) fTableViewer.getSelection();
	int size = selection.size();
	fRemoveButton.setEnabled(size > 0);
	fEditButton.setEnabled(size == 1);
	//fDuplicateButton.setEnabled(size == 1);
	}

	/**
	* Returns the target platform service.
	*
	* @return target platform service
	*/
	private ITargetPlatformService getTargetService() {
	return (ITargetPlatformService) PDECore.getDefault().acquireService(ITargetPlatformService.class.getName());
	}

	/* (non-Javadoc)
	* @see org.eclipse.ui.IWorkbenchPreferencePage#init(org.eclipse.ui.IWorkbench)
	*/
	public void init(IWorkbench workbench) {
	// ensures default targets are created when page is opened (if not created yet)
	PluginModelManager manager = PDECore.getDefault().getModelManager();
	manager.getExternalModelManager();
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.PreferencePage#performDefaults()
	*/
	public void performDefaults() {
	// add a default target platform and select it (or just select it if present)
	ITargetPlatformService service = getTargetService();
	if (service instanceof TargetPlatformService) {
	TargetPlatformService ts = (TargetPlatformService) service;
	ITargetDefinition deflt = ts.newDefaultTargetDefinition();
	Iterator iterator = fTargets.iterator();
	ITargetDefinition reuse = null;
	while (iterator.hasNext()) {
	TargetDefinition existing = (TargetDefinition) iterator.next();
	if (existing.isContentEquivalent(deflt)) {
	reuse = existing;
	break;
	}
	}
	if (reuse != null) {
	deflt = reuse;
	} else {
	fTargets.add(deflt);
	}
	fTableViewer.refresh();
	fTableViewer.setCheckedElements(new Object[] {deflt});
	}
	super.performDefaults();
	}

	/* (non-Javadoc)
	* @see org.eclipse.jface.preference.PreferencePage#performOk()
	*/
	public boolean performOk() {
	ITargetPlatformService service = getTargetService();
	if (service == null) {
	return false;
	}

	// determine if default target has changed
	ITargetDefinition toLoad = null;
	boolean load = false;
	try {
	ITargetHandle prev = service.getWorkspaceTargetHandle();
	ITargetHandle currH = null;
	ITargetDefinition currD = null;
	Object[] elements = fTableViewer.getCheckedElements();
	if (elements.length > 0) {
	currD = (ITargetDefinition) elements[0];
	currH = currD.getHandle();
	}
	if (prev == null) {
	if (currH != null) {
	toLoad = currD;
	load = true;
	}
	} else {
	if (currH == null) {
	// load empty
	load = true;
	} else if (!prev.equals(currH)) {
	toLoad = currD;
	load = true;
	} else {
	ITargetDefinition original = prev.getTargetDefinition();
	// TODO: should just check for structural changes
	if (((TargetDefinition) original).isContentEquivalent(currD)) {
	load = false;
	} else {
	load = true;
	toLoad = currD;
	}
	}
	}
	} catch (CoreException e) {
	ErrorDialog.openError(getShell(), PDEUIMessages.TargetPlatformPreferencePage2_8, PDEUIMessages.TargetPlatformPreferencePage2_9, e.getStatus());
	return false;
	}

	// Remove any definitions that have been removed
	// TODO should we prompt? (only if workspace files?)
	Iterator iterator = fRemoved.iterator();
	while (iterator.hasNext()) {
	ITargetDefinition target = (ITargetDefinition) iterator.next();
	try {
	service.deleteTarget(target.getHandle());
	} catch (CoreException e) {
	ErrorDialog.openError(getShell(), PDEUIMessages.TargetPlatformPreferencePage2_8, PDEUIMessages.TargetPlatformPreferencePage2_11, e.getStatus());
	return false;
	}
	}
	// save others that are dirty
	iterator = fTargets.iterator();
	while (iterator.hasNext()) {
	ITargetDefinition def = (ITargetDefinition) iterator.next();
	boolean save = true;
	if (def.getHandle().exists()) {
	try {
	ITargetDefinition original = def.getHandle().getTargetDefinition();
	if (((TargetDefinition) original).isContentEqual(def)) {
	save = false;
	}
	} catch (CoreException e) {
	// failed to generate original
	setErrorMessage(e.getMessage());
	return false;
	}
	}
	if (save) {
	try {
	service.saveTargetDefinition(def);
	} catch (CoreException e) {
	setErrorMessage(e.getMessage());
	return false;
	}
	}
	}

	// set workspace target if required
	if (load) {
	// TODO: prompt to warn of build? (like JRE page)
	Job job = new LoadTargetDefinitionJob(toLoad);
	job.schedule();
	}

	return super.performOk();
	}

	}