ShowInHandler.java :  » IDE-Eclipse » ui-workbench » org » eclipse » ui » internal » Java Open Source

/*******************************************************************************
 * Copyright (c) 2008, 2009 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
 ******************************************************************************/

package org.eclipse.ui.internal;

import java.util.Map;

import org.eclipse.core.commands.AbstractHandler;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;

import org.eclipse.jface.viewers.ISelection;

import org.eclipse.ui.ISourceProvider;
import org.eclipse.ui.ISources;
import org.eclipse.ui.IViewPart;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.commands.IElementUpdater;
import org.eclipse.ui.handlers.HandlerUtil;
import org.eclipse.ui.internal.services.WorkbenchSourceProvider;
import org.eclipse.ui.internal.util.Util;
import org.eclipse.ui.menus.UIElement;
import org.eclipse.ui.part.IShowInTarget;
import org.eclipse.ui.part.ShowInContext;
import org.eclipse.ui.services.ISourceProviderService;
import org.eclipse.ui.views.IViewDescriptor;
import org.eclipse.ui.views.IViewRegistry;

/**
 * The show in command, which only needs a target id.
 * 
 * @since 3.4
 */
public class ShowInHandler extends AbstractHandler implements IElementUpdater {
  static final String TARGET_ID = "org.eclipse.ui.navigate.showIn.targetId"; //$NON-NLS-1$

  /*
   * (non-Javadoc)
   * 
   * @see org.eclipse.core.commands.IHandler#execute(org.eclipse.core.commands.ExecutionEvent)
   */
  public Object execute(ExecutionEvent event) throws ExecutionException {
    String targetId = event.getParameter(TARGET_ID);
    if (targetId == null) {
      throw new ExecutionException("No targetId specified"); //$NON-NLS-1$
    }

    final IWorkbenchWindow activeWorkbenchWindow = HandlerUtil.getActiveWorkbenchWindowChecked(event);
    ISourceProviderService sps = (ISourceProviderService)activeWorkbenchWindow.getService(ISourceProviderService.class);
    if (sps != null) {
      ISourceProvider sp = sps.getSourceProvider(ISources.SHOW_IN_SELECTION);
      if (sp instanceof WorkbenchSourceProvider) {
        ((WorkbenchSourceProvider)sp).checkActivePart(true);
      }
    }

    ShowInContext context = getContext(HandlerUtil
        .getShowInSelection(event), HandlerUtil.getShowInInput(event));
    if (context == null) {
      return null;
    }

    IWorkbenchPage page= activeWorkbenchWindow.getActivePage();

    try {
      IViewPart view = page.showView(targetId);
      IShowInTarget target = getShowInTarget(view);
      if (!(target != null && target.show(context))) {
        page.getWorkbenchWindow().getShell().getDisplay().beep();
      }
      ((WorkbenchPage) page).performedShowIn(targetId); // TODO: move
      // back up
    } catch (PartInitException e) {
      throw new ExecutionException("Failed to show in", e); //$NON-NLS-1$
    }

    return null;
  }

  /**
   * Returns the <code>ShowInContext</code> to show in the selected target,
   * or <code>null</code> if there is no valid context to show.
   * <p>
   * This implementation obtains the context from global variables provide.
   * showInSelection and showInInput should be available.
   * <p>
   * 
   * @return the <code>ShowInContext</code> to show or <code>null</code>
   */
  private ShowInContext getContext(ISelection showInSelection, Object input) {
    if (input == null && showInSelection == null) {
      return null;
    }
    return new ShowInContext(input, showInSelection);
  }

  /**
   * Returns the <code>IShowInTarget</code> for the given part, or
   * <code>null</code> if it does not provide one.
   * 
   * @param targetPart
   *            the target part
   * @return the <code>IShowInTarget</code> or <code>null</code>
   */
  private IShowInTarget getShowInTarget(IWorkbenchPart targetPart) {
    return (IShowInTarget) Util.getAdapter(targetPart, IShowInTarget.class);
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.eclipse.ui.commands.IElementUpdater#updateElement(org.eclipse.ui.menus.UIElement,
   *      java.util.Map)
   */
  public void updateElement(UIElement element, Map parameters) {
    String targetId = (String) parameters.get(TARGET_ID);
    if (targetId == null || targetId.length() == 0) {
      return;
    }
    IViewRegistry reg = WorkbenchPlugin.getDefault().getViewRegistry();
    IViewDescriptor desc = reg.find(targetId);
    if (desc != null) {
      element.setIcon(desc.getImageDescriptor());
      element.setText(desc.getLabel());
    }
  }
}