Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2010 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 * James Blackburn (Broadcom Corp.) - Bug 294628 multiple selection *******************************************************************************/ package org.eclipse.ui.dialogs; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.preference.PreferenceDialog; import org.eclipse.jface.viewers.ISelectionProvider; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.window.IShellProvider; import org.eclipse.jface.window.SameShellProvider; import org.eclipse.swt.widgets.Shell; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.actions.SelectionProviderAction; import org.eclipse.ui.internal.IWorkbenchHelpContextIds; import org.eclipse.ui.internal.WorkbenchMessages; import org.eclipse.ui.internal.dialogs.PropertyDialog; import org.eclipse.ui.internal.dialogs.PropertyPageContributorManager; /** * Standard action for opening a Property Pages Dialog on the currently selected * element. * <p> * This class may be instantiated; it is not intended to be subclassed. * </p> * <p> * Generally speaking, this action is useful in pop-up menus because it allows * the user to browse and change properties of selected elements. When * performed, the action will bring up a Property Pages Dialog containing * property pages registered with the workbench for elements of the selected * type. * </p> * <p> * Although the action is capable of calculating if there are any applicable * pages for the current selection, this calculation is costly because it * require searching the workbench registry. Where performance is critical, the * action can simply be added to the pop-up menu. In the event of no applicable * pages, the action will just open an appropriate message dialog. * </p> * @noextend This class is not intended to be subclassed by clients. */ public class PropertyDialogAction extends SelectionProviderAction { /** * Provides the shell in which to open the property dialog. */ private IShellProvider shellProvider; /** * The id of the page to open up on. */ private String initialPageId; /** * Creates a new action for opening a property dialog on the elements from * the given selection provider. * * @param shell * the shell in which the dialog will open * @param provider * the selection provider whose elements the property dialog will * describe * @deprecated use PropertyDialogAction(IShellProvider, ISelectionProvider) */ public PropertyDialogAction(Shell shell, ISelectionProvider provider) { this(new SameShellProvider(shell), provider); } /** * Creates a new action for opening a property dialog on the elements from * the given selection provider. * * @param shell * provides the shell in which the dialog will open * @param provider * the selection provider whose elements the property dialog will * describe * @since 3.1 */ public PropertyDialogAction(IShellProvider shell, ISelectionProvider provider) { super(provider, WorkbenchMessages.PropertyDialog_text); Assert.isNotNull(shell); this.shellProvider = shell; setToolTipText(WorkbenchMessages.PropertyDialog_toolTip); PlatformUI.getWorkbench().getHelpSystem().setHelp(this, IWorkbenchHelpContextIds.PROPERTY_DIALOG_ACTION); } /** * Returns whether the provided selection has pages registered in the property * page manager. * * @param object * @return boolean */ private boolean hasPropertyPagesFor(IStructuredSelection object) { return PropertyPageContributorManager.getManager().getApplicableContributors(object).size() != 0; } /** * Returns whether this action is actually applicable to the current * selection. If this action is disabled, it will return <code>false</code> * without further calculation. If it is enabled, it will check with the * workbench's property page manager to see if there are any property pages * registered for the selected element's type. * <p> * This method is generally too expensive to use when updating the enabled * state of the action on each selection change. * </p> * * @return <code>true</code> if the selection is not empty and there are * property pages for the selected element, and <code>false</code> * otherwise */ public boolean isApplicableForSelection() { if (!isEnabled()) { return false; } return isApplicableForSelection(getStructuredSelection()); } /** * Returns whether this action is applicable to the current selection. This * checks that the selection is not empty, and checks with the workbench's * property page manager to see if there are any property pages registered * for the selected element's type. * <p> * This method is generally too expensive to use when updating the enabled * state of the action on each selection change. * </p> * * @param selection * The selection to test * @return <code>true</code> if the selection is of not empty and there are * property pages for the selected element, and <code>false</code> * otherwise */ public boolean isApplicableForSelection(IStructuredSelection selection) { return !selection.isEmpty() && hasPropertyPagesFor(selection); } /* (non-Javadoc) * @see org.eclipse.jface.action.IAction#run() */ public void run() { PreferenceDialog dialog = createDialog(); if (dialog != null) { dialog.open(); } } /** * Create the dialog for the receiver. If no pages are found, an informative * message dialog is presented instead. * * @return PreferenceDialog or <code>null</code> if no applicable pages * are found. * @since 3.1 */ public PreferenceDialog createDialog() { if (getStructuredSelection().isEmpty()) return null; return PropertyDialog.createDialogOn(shellProvider.getShell(), initialPageId, getStructuredSelection()); } /* (non-Javadoc) * @see org.eclipse.ui.actions.SelectionProviderAction#selectionChanged(org.eclipse.jface.viewers.IStructuredSelection) */ public void selectionChanged(IStructuredSelection selection) { setEnabled(!selection.isEmpty()); } }