bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/quickaccess/QuickAccessContents.java

/*******************************************************************************
 * Copyright (c) 2005, 2016 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
 *     Tom Hochstein (Freescale) - Bug 393703 - NotHandledException selecting inactive command under 'Previous Choices' in Quick access
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 472654, 491272, 491398
 *     Leung Wang Hei <gemaspecial@yahoo.com.hk> - Bug 483343
 *     Patrik Suzzi <psuzzi@gmail.com> - Bug 491291, 491529, 491293, 492434
 *******************************************************************************/
package org.eclipse.ui.internal.quickaccess;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.eclipse.core.runtime.Adapters;
import org.eclipse.jface.bindings.TriggerSequence;
import org.eclipse.jface.dialogs.IDialogSettings;
import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.TableColumnLayout;
import org.eclipse.jface.resource.FontDescriptor;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.resource.LocalResourceManager;
import org.eclipse.jface.util.Util;
import org.eclipse.jface.viewers.ColumnWeightData;
import org.eclipse.osgi.util.NLS;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ControlAdapter;
import org.eclipse.swt.events.ControlEvent;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.MouseAdapter;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseMoveListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.TextLayout;
import org.eclipse.swt.graphics.TextStyle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.IWorkbenchPreferenceConstants;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.internal.WorkbenchPlugin;
import org.eclipse.ui.keys.IBindingService;
import org.eclipse.ui.themes.ColorUtil;


/**
 * Provides the contents for the quick access shell created by
 * {@link SearchField}. This was also used by {@link QuickAccessDialog} prior to
 * e4. The SearchField is responsible for handling opening and closing the shell
 * as well as setting {@link #setShowAllMatches(boolean)}.
 */
public abstract class QuickAccessContents {
	/**
	 * When opened in a popup we were given the command used to open it. Now
	 * that we have a shell, we are just using a hard coded command id.
	 */
	private static final String QUICK_ACCESS_COMMAND_ID = "org.eclipse.ui.window.quickAccess"; //$NON-NLS-1$
	private static final int INITIAL_COUNT_PER_PROVIDER = 5;
	private static final int MAX_COUNT_TOTAL = 20;

	protected Text filterText;

	private QuickAccessProvider[] providers;

	protected Table table;
	protected Label infoLabel;

	private LocalResourceManager resourceManager = new LocalResourceManager(
			JFaceResources.getResources());

	protected String rememberedText;

	/**
	 * A color for dulled out items created by mixing the table foreground. Will
	 * be disposed when the {@link #resourceManager} is disposed.
	 */
	private Color grayColor;
	private TextLayout textLayout;
	private boolean showAllMatches = false;
	protected boolean resized = false;
	private TriggerSequence keySequence;

	public QuickAccessContents(QuickAccessProvider[] providers) {
		this.providers = providers;
	}

	/**
	 * Returns the number of items the table can fit in its current layout
	 */
	private int computeNumberOfItems() {
		Rectangle rect = table.getClientArea ();
		int itemHeight = table.getItemHeight ();
		int headerHeight = table.getHeaderHeight ();
		return (rect.height - headerHeight + itemHeight - 1) / (itemHeight + table.getGridLineWidth());
	}

	/**
	 * Refreshes the contents of the quick access shell
	 *
	 * @param filter
	 *            The filter text to apply to results
	 *
	 */
	public void refresh(String filter) {
		if (table != null) {
			boolean filterTextEmpty = filter.length() == 0;

			// perfect match, to be selected in the table if not null
			QuickAccessElement perfectMatch = getPerfectMatch(filter);
			List<QuickAccessEntry>[] entries = computeMatchingEntries(filter, perfectMatch);
			int selectionIndex = refreshTable(perfectMatch, entries);

			if (table.getItemCount() > 0) {
				table.setSelection(selectionIndex);
				hideHintText();
			} else if (filterTextEmpty) {
				showHintText(QuickAccessMessages.QuickAccess_StartTypingToFindMatches, grayColor);
			} else {
				showHintText(QuickAccessMessages.QuickAccessContents_NoMatchingResults, grayColor);
			}

			// update info as-you-type
			updateInfoLabel();

			updateFeedback(filterTextEmpty, showAllMatches);
		}
	}

	/**
	 * Allows the quick access content owner to mark a quick access element as
	 * being a perfect match, putting it at the start of the table.
	 *
	 * @param filter
	 *            the filter text used to find a match
	 * @return an element to be put at the top of the table or <code>null</code>
	 */
	protected abstract QuickAccessElement getPerfectMatch(String filter);

	/**
	 * Notifies the quick access content owner that the contents of the table
	 * have been changed.
	 *
	 * @param filterTextEmpty
	 *            whether the filter text used to calculate matches was empty
	 * @param showAllMatches
	 *            whether the results were constrained by the size of the dialog
	 *
	 */
	protected abstract void updateFeedback(boolean filterTextEmpty, boolean showAllMatches);

	/**
	 * Sets whether to display all matches to the current filter or limit the
	 * results. Will refresh the table contents and update the info label.
	 *
	 * @param showAll
	 *            whether to display all matches
	 */
	public void setShowAllMatches(boolean showAll) {
		if (showAllMatches != showAll) {
			showAllMatches = showAll;
			updateInfoLabel();
			refresh(filterText.getText().toLowerCase());
		}
	}

	private void updateInfoLabel() {
		if (infoLabel != null) {
			TriggerSequence sequence = getTriggerSequence();
			boolean forceHide = (getNumberOfFilteredResults() == 0)
					|| (showAllMatches && (table.getItemCount() <= computeNumberOfItems()));
			if (sequence == null || forceHide) {
				infoLabel.setText(""); //$NON-NLS-1$
			} else if (showAllMatches) {
				infoLabel.setText(
						NLS.bind(QuickAccessMessages.QuickAccessContents_PressKeyToLimitResults, sequence.format()));
			} else {
				infoLabel
						.setText(NLS.bind(QuickAccessMessages.QuickAccess_PressKeyToShowAllMatches, sequence.format()));
			}
			infoLabel.getParent().layout(true);
		}
	}

	/**
	 * Returns the trigger sequence that can be used to open the quick access
	 * dialog as well as toggle the show all results feature. Can return
	 * <code>null</code> if no trigger sequence is known.
	 *
	 * @return the trigger sequence used to open the quick access or
	 *         <code>null</code>
	 */
	public TriggerSequence getTriggerSequence() {
		if (keySequence == null) {
			IBindingService bindingService =
					Adapters.adapt(PlatformUI.getWorkbench(), IBindingService.class);
			keySequence = bindingService.getBestActiveBindingFor(QUICK_ACCESS_COMMAND_ID);
		}
		return keySequence;
	}

	/**
	 * Return whether the shell is currently set to display all matches or limit
	 * the results.
	 *
	 * @return whether all matches will be displayed
	 */
	public boolean getShowAllMatches() {
		return showAllMatches;
	}

	private int refreshTable(QuickAccessElement perfectMatch, List<QuickAccessEntry>[] entries) {
		if (table.getItemCount() > entries.length
				&& table.getItemCount() - entries.length > 20) {
			table.removeAll();
		}
		TableItem[] items = table.getItems();
		int selectionIndex = -1;
		int index = 0;
		for (int i = 0; i < providers.length; i++) {
			if (entries[i] != null) {
				boolean firstEntry = true;
				for (Iterator<QuickAccessEntry> it = entries[i].iterator(); it.hasNext();) {
					QuickAccessEntry entry = it.next();
					entry.firstInCategory = firstEntry;
					firstEntry = false;
					if (!it.hasNext()) {
						entry.lastInCategory = true;
					}
					TableItem item;
					if (index < items.length) {
						item = items[index];
						table.clear(index);
					} else {
						item = new TableItem(table, SWT.NONE);
					}
					if (perfectMatch == entry.element && selectionIndex == -1) {
						selectionIndex = index;
					}
					item.setData(entry);
					item.setText(0, entry.provider.getName());
					item.setText(1, entry.element.getLabel());
					if (Util.isWpf()) {
						item.setImage(1, entry.getImage(entry.element,
							resourceManager));
					}
					index++;
				}
			}
		}
		if (index < items.length) {
			table.remove(index, items.length - 1);
		}
		if (selectionIndex == -1) {
			selectionIndex = 0;
		}
		return selectionIndex;
	}

	int numberOfFilteredResults;

	/**
	 * Compute how many items are effectively filtered at a specific point in
	 * time. So doing, the quick access content can perform operations that
	 * depends on this number, i.e. hide the info label.
	 *
	 * @return number number of elements filtered
	 */
	protected int getNumberOfFilteredResults() {
		return numberOfFilteredResults;
	}

	/**
	 * Returns a list per provider containing matching {@link QuickAccessEntry}
	 * that should be displayed in the table given a text filter and a perfect
	 * match entry that should be given priority. The number of items returned
	 * is affected by {@link #getShowAllMatches()} and the size of the table's
	 * composite.
	 *
	 * @param filter
	 *            the string text filter to apply, possibly empty
	 * @param perfectMatch
	 *            a quick access element that should be given priority or
	 *            <code>null</code>
	 * @return the array of lists (one per provider) containg the quick access
	 *         entries that should be added to the table, possibly empty
	 */
	private List<QuickAccessEntry>[] computeMatchingEntries(String filter,
			QuickAccessElement perfectMatch) {
		// collect matches in an array of lists
		@SuppressWarnings("unchecked")
		List<QuickAccessEntry>[] entries = new List[providers.length];

		int maxCount = computeNumberOfItems();
		int[] indexPerProvider = new int[providers.length];
		int countPerProvider = INITIAL_COUNT_PER_PROVIDER;
		int prevPick = 0;
		int countTotal = 0;
		boolean perfectMatchAdded = true;
		if (perfectMatch != null) {
			// reserve one entry for the perfect match
			maxCount--;
			perfectMatchAdded = false;
		}
		boolean done;
		String category = null;
		do {
			// will be set to false if we find a provider with remaining
			// elements
			done = true;
			// check for a category filter, like "Views: "
			Matcher categoryMatcher = getCategoryPattern().matcher(filter);
			if (categoryMatcher.matches()) {
				category = categoryMatcher.group(1);
				filter = category + " " + categoryMatcher.group(2); //$NON-NLS-1$
			}
			for (int i = 0; i < providers.length
					&& (showAllMatches || countTotal < maxCount); i++) {
				if (entries[i] == null) {
					entries[i] = new ArrayList<>();
					indexPerProvider[i] = 0;
				}
				int count = 0;
				QuickAccessProvider provider = providers[i];
				// when category is specified, skip providers except the
				// specified one and the previous pick provider
				boolean isPreviousPickProvider = (provider instanceof PreviousPicksProvider);
				if (category != null && !category.equalsIgnoreCase(provider.getName()) && !isPreviousPickProvider) {
					continue;
				}
				if (filter.length() > 0 || provider.isAlwaysPresent() || showAllMatches) {
					QuickAccessElement[] sortedElements = provider.getElementsSorted();
					List<QuickAccessEntry> poorFilterMatches = new ArrayList<>();

					// count number or previous picks
					if ((provider instanceof PreviousPicksProvider)) {
						prevPick = sortedElements.length;
					}

					int j = indexPerProvider[i];
					while (j < sortedElements.length
							&& (showAllMatches || (count < countPerProvider && countTotal < maxCount))) {
						QuickAccessElement element = sortedElements[j];
						QuickAccessEntry entry = null;
						if (filter.length() == 0) {
							if (i == 0 || showAllMatches) {
								entry = new QuickAccessEntry(element, provider, new int[0][0],
										new int[0][0], QuickAccessEntry.MATCH_PERFECT);
							} else {
								entry = null;
							}
						} else {
							QuickAccessEntry possibleMatch = element.match(filter, provider);
							// We only have limited space so only display
							// excellent filter matches (Bug 398455)
							if (possibleMatch != null) {
								if (possibleMatch.getMatchQuality() <= QuickAccessEntry.MATCH_EXCELLENT) {
									entry = possibleMatch;
								} else {
									poorFilterMatches.add(possibleMatch);
								}
							}

						}
						if (entryEnabled(provider, entry)) {
							entries[i].add(entry);
							count++;
							countTotal++;
							if (i == 0 && entry.element == perfectMatch) {
								perfectMatchAdded = true;
								maxCount = MAX_COUNT_TOTAL;
							}
						}

						j++;
					}

					indexPerProvider[i] = j;
					// If there were low quality matches and there is still
					// room, add them (Bug 398455)
					for (Iterator<QuickAccessEntry> iterator = poorFilterMatches.iterator(); iterator
							.hasNext()
							&& (showAllMatches || (count < countPerProvider && countTotal < maxCount));) {
						QuickAccessEntry quickAccessEntry = iterator.next();
						entries[i].add(quickAccessEntry);
						count++;
						countTotal++;
						if (i == 0 && quickAccessEntry.element == perfectMatch) {
							perfectMatchAdded = true;
							maxCount = MAX_COUNT_TOTAL;
						}
					}
					if (j < sortedElements.length) {
						done = false;
					}
				}
			}
			// from now on, add one element per provider
			countPerProvider = 1;
		} while ((showAllMatches || countTotal < maxCount) && !done);
		if (!perfectMatchAdded) {
			QuickAccessEntry entry = perfectMatch.match(filter, providers[0]);
			if (entryEnabled(providers[0], entry)) {
				if (entries[0] == null) {
					entries[0] = new ArrayList<>();
					indexPerProvider[0] = 0;
				}
				entries[0].add(entry);
			}
		}
		// number of items matching the filtered search
		numberOfFilteredResults = countTotal - prevPick;
		return entries;
	}

	Pattern categoryPattern;

	/**
	 * Return a pattern like {@code "^(:?Views|Perspective):\\s?(.*)"}, with all
	 * the provider names separated by semicolon.
	 *
	 * @return Returns the patternProvider.
	 */
	protected Pattern getCategoryPattern() {
		if (categoryPattern == null) {
			// build regex like "^(:?Views|Perspective):\\s?(.*)"
			StringBuilder sb = new StringBuilder();
			sb.append("^(:?"); //$NON-NLS-1$
			for (int i = 0; i < providers.length; i++) {
				if (i != 0)
					sb.append("|"); //$NON-NLS-1$
				sb.append(providers[i].getName());
			}
			sb.append("):\\s?(.*)"); //$NON-NLS-1$
			String regex = sb.toString();
			categoryPattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);
		}
		return categoryPattern;
	}

	/**
	 * @param provider
	 * @param entry
	 * @return <code>true</code> if the entry is enabled
	 */
	private boolean entryEnabled(QuickAccessProvider provider, QuickAccessEntry entry) {
		if (entry == null) {
			return false;
		}

		// For a previous pick provider, check that the original provider does
		// also provide the element
		if (provider instanceof PreviousPicksProvider) {
			QuickAccessElement element = entry.element;
			final QuickAccessProvider originalProvider = element.getProvider();
			QuickAccessElement match = originalProvider.getElementForId(element.getId());
			return match != null;
		}

		return true;
	}

	private void doDispose() {
		if (textLayout != null && !textLayout.isDisposed()) {
			textLayout.dispose();
		}
		if (resourceManager != null) {
			// Disposing the resource manager will dispose the color
			resourceManager.dispose();
			resourceManager = null;
		}
	}

	protected IDialogSettings getDialogSettings() {
		final IDialogSettings workbenchDialogSettings = WorkbenchPlugin
				.getDefault().getDialogSettings();
		IDialogSettings result = workbenchDialogSettings.getSection(getId());
		if (result == null) {
			result = workbenchDialogSettings.addNewSection(getId());
		}
		return result;
	}

	protected String getId() {
		return "org.eclipse.ui.internal.QuickAccess"; //$NON-NLS-1$
	}

	protected abstract void handleElementSelected(String text, Object selectedElement);

	private void handleSelection() {
		QuickAccessElement selectedElement = null;
		String text = filterText.getText().toLowerCase();
		if (table.getSelectionCount() == 1) {
			QuickAccessEntry entry = (QuickAccessEntry) table
					.getSelection()[0].getData();
			selectedElement = entry == null ? null : entry.element;
		}
		if (selectedElement != null) {
			doClose();
			handleElementSelected(text, selectedElement);
		}
	}

	/**
	 * Should be called by the owner of the parent composite when the shell is
	 * being activated (made visible). This allows the show all keybinding to be
	 * updated.
	 */
	public void preOpen() {
		// Make sure we always start filtering
		setShowAllMatches(false);
		// In case the key binding has changed, update the label
		keySequence = null;
		updateInfoLabel();
	}

	/**
	 * Informs the owner of the parent composite that the quick access dialog
	 * should be closed
	 */
	protected abstract void doClose();

	/**
	 * Allows the dialog contents to interact correctly with the text box used to open it
	 * @param filterText text box to hook up
	 */
	public void hookFilterText(Text filterText) {
		this.filterText = filterText;
		filterText.addKeyListener(new KeyListener() {
			@Override
			public void keyPressed(KeyEvent e) {
				switch (e.keyCode) {
				case SWT.CR:
				case SWT.KEYPAD_CR:
					handleSelection();
					break;
				case SWT.ARROW_DOWN:
					int index = table.getSelectionIndex();
					if (index != -1 && table.getItemCount() > index + 1) {
						table.setSelection(index + 1);
					}
					break;
				case SWT.ARROW_UP:
					index = table.getSelectionIndex();
					if (index != -1 && index >= 1) {
						table.setSelection(index - 1);
					}
					break;
				case SWT.ESC:
					doClose();
					break;
				}
			}

			@Override
			public void keyReleased(KeyEvent e) {
				// do nothing
			}
		});
		filterText.addModifyListener(new ModifyListener() {
			@Override
			public void modifyText(ModifyEvent e) {
				String text = ((Text) e.widget).getText().toLowerCase();
				refresh(text);
			}
		});
	}

	private Text hintText;
	private boolean displayHintText;

	/** Create HintText as child of the given parent composite */
	Text createHintText(Composite composite, int defaultOrientation) {
		hintText = new Text(composite, SWT.FILL);
		hintText.setOrientation(defaultOrientation);
		displayHintText = true;
		return hintText;
	}

	/** Hide the hint text */
	void hideHintText() {
		if (displayHintText) {
			setHintTextToDisplay(false);
		}
	}

	/** Show the hint text with the given color */
	void showHintText(String text, Color color) {
		if (hintText == null) {
			// toolbar hidden
			return;
		}
		hintText.setText(text);
		if (color != null) {
			hintText.setForeground(color);
		}
		if (!displayHintText) {
			setHintTextToDisplay(true);
		}
	}

	/**
	 * Sets hint text to be displayed and requests the layout
	 *
	 * @param toDisplay
	 */
	private void setHintTextToDisplay(boolean toDisplay) {
		GridData data = (GridData) hintText.getLayoutData();
		data.exclude = !toDisplay;
		hintText.setVisible(toDisplay);
		hintText.requestLayout();
		this.displayHintText = toDisplay;
	}

	/**
	 * Creates the table providing the contents for the quick access dialog
	 *
	 * @param composite parent composite with {@link GridLayout}
	 * @param defaultOrientation the window orientation to use for the table {@link SWT#RIGHT_TO_LEFT} or {@link SWT#LEFT_TO_RIGHT}
	 * @return the created table
	 */
	public Table createTable(Composite composite, int defaultOrientation) {
		composite.addDisposeListener(new DisposeListener() {
			@Override
			public void widgetDisposed(DisposeEvent e) {
				doDispose();
			}
		});
		Composite tableComposite = new Composite(composite, SWT.NONE);
		GridDataFactory.fillDefaults().grab(true, true).applyTo(tableComposite);
		TableColumnLayout tableColumnLayout = new TableColumnLayout();
		tableComposite.setLayout(tableColumnLayout);
		table = new Table(tableComposite, SWT.SINGLE | SWT.FULL_SELECTION);
		textLayout = new TextLayout(table.getDisplay());
		textLayout.setOrientation(defaultOrientation);
		Font boldFont = resourceManager.createFont(FontDescriptor.createFrom(
				JFaceResources.getDialogFont()).setStyle(SWT.BOLD));
		textLayout.setFont(table.getFont());
		textLayout.setText(QuickAccessMessages.QuickAccess_AvailableCategories);
		int maxProviderWidth = (textLayout.getBounds().width);
		textLayout.setFont(boldFont);
		for (int i = 0; i < providers.length; i++) {
			QuickAccessProvider provider = providers[i];
			textLayout.setText(provider.getName());
			int width = (textLayout.getBounds().width);
			if (width > maxProviderWidth) {
				maxProviderWidth = width;
			}
		}
		tableColumnLayout.setColumnData(new TableColumn(table, SWT.NONE), new ColumnWeightData(0, maxProviderWidth));
		tableColumnLayout.setColumnData(new TableColumn(table, SWT.NONE), new ColumnWeightData(100, 100));
		table.getShell().addControlListener(new ControlAdapter() {
			@Override
			public void controlResized(ControlEvent e) {
				if (!showAllMatches) {
					if (!resized) {
						resized = true;
						e.display.timerExec(100, new Runnable() {
							@Override
							public void run() {
								if (table != null && !table.isDisposed() && filterText !=null && !filterText.isDisposed()) {
									refresh(filterText.getText().toLowerCase());
								}
								resized = false;
							}
						});
					}
				}
			}
		});

		table.addKeyListener(new KeyListener() {
			@Override
			public void keyPressed(KeyEvent e) {
				if (e.keyCode == SWT.ARROW_UP && table.getSelectionIndex() == 0) {
					filterText.setFocus();
				} else if (e.character == SWT.ESC) {
					doClose();
				}
			}

			@Override
			public void keyReleased(KeyEvent e) {
				// do nothing
			}
		});
		table.addMouseListener(new MouseAdapter() {
			@Override
			public void mouseUp(MouseEvent e) {

				if (table.getSelectionCount() < 1)
					return;

				if (e.button != 1)
					return;

				if (table.equals(e.getSource())) {
					Object o = table.getItem(new Point(e.x, e.y));
					TableItem selection = table.getSelection()[0];
					if (selection.equals(o))
						handleSelection();
				}
			}
		});

		table.addMouseMoveListener(new MouseMoveListener() {
			TableItem lastItem = null;

			@Override
			public void mouseMove(MouseEvent e) {
				if (table.equals(e.getSource())) {
					Object o = table.getItem(new Point(e.x, e.y));
					if (lastItem == null ^ o == null) {
						table.setCursor(o == null ? null : table.getDisplay().getSystemCursor(
								SWT.CURSOR_HAND));
					}
					if (o instanceof TableItem) {
						if (!o.equals(lastItem)) {
							lastItem = (TableItem) o;
							table.setSelection(new TableItem[] { lastItem });
						}
					} else if (o == null) {
						lastItem = null;
					}
				}
			}
		});

		table.addSelectionListener(new SelectionListener() {
			@Override
			public void widgetSelected(SelectionEvent e) {
				// do nothing
			}

			@Override
			public void widgetDefaultSelected(SelectionEvent e) {
				handleSelection();
			}
		});

		final TextStyle boldStyle;
		if (PlatformUI.getPreferenceStore().getBoolean(
				IWorkbenchPreferenceConstants.USE_COLORED_LABELS)) {
			boldStyle = new TextStyle(boldFont, null, null);
			grayColor = resourceManager.createColor(ColorUtil.blend(table.getBackground().getRGB(),
					table.getForeground().getRGB()));
		} else {
			boldStyle = null;
		}
		Listener listener = new Listener() {
			@Override
			public void handleEvent(Event event) {
				QuickAccessEntry entry = (QuickAccessEntry) event.item.getData();
				if (entry != null) {
					switch (event.type) {
					case SWT.MeasureItem:
						entry.measure(event, textLayout, resourceManager, boldStyle);
						break;
					case SWT.PaintItem:
						entry.paint(event, textLayout, resourceManager, boldStyle, grayColor);
						break;
					case SWT.EraseItem:
						entry.erase(event);
						break;
					}
				}
			}
		};
		table.addListener(SWT.MeasureItem, listener);
		table.addListener(SWT.EraseItem, listener);
		table.addListener(SWT.PaintItem, listener);

		return table;
	}

	/**
	 * Creates a label which will display the key binding to expand
	 * the search results.
	 *
	 * @param parent parent composite with {@link GridLayout}
	 * @return the created label
	 */
	public Label createInfoLabel(Composite parent) {
		infoLabel = new Label(parent, SWT.NONE);
		infoLabel.setFont(parent.getFont());
		infoLabel.setForeground(grayColor);
		infoLabel.setBackground(table.getBackground());
		GridData gd = new GridData(GridData.FILL_HORIZONTAL);
		gd.horizontalAlignment = SWT.RIGHT;
		gd.grabExcessHorizontalSpace = false;
		infoLabel.setLayoutData(gd);
		updateInfoLabel();
		return infoLabel;
	}

	public void resetProviders() {
		for (QuickAccessProvider provider : providers) {
			provider.reset();
		}
	}

}