contentproposaladapter.java

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							Thread.sleep(POPUP_DELAY);
						} catch (InterruptedException e) {
						}
						if (!isValid()) {
							return;
						}
						getShell().getDisplay().syncExec(new Runnable() {
							public void run() {
								// Query the current selection since we have
								// been delayed
								IContentProposal p = getSelectedProposal();
								if (p != null) {
									if (infoPopup == null) {
										infoPopup = new InfoPopupDialog(
												getShell());
										infoPopup.open();
										infoPopup.getShell()
												.addDisposeListener(
														new DisposeListener() {
															public void widgetDisposed(
																	DisposeEvent event) {
																infoPopup = null;
															}
														});
									}
									infoPopup.setContents(p.getDescription());
									pendingDescriptionUpdate = false;

								}
							}
						});
					}
				};
				Thread t = new Thread(runnable);
				t.start();
			}
		}

		/*
		 * Accept the current proposal.
		 */
		private void acceptCurrentProposal() {
			// Close before accepting the proposal.
			// This is important so that the cursor position can be
			// properly restored at acceptance, which does not work without
			// focus on some controls.
			// See https://bugs.eclipse.org/bugs/show_bug.cgi?id=127108
			IContentProposal proposal = getSelectedProposal();
			close();
			proposalAccepted(proposal);
		}

		/*
		 * Request the proposals from the proposal provider, and recompute any
		 * caches. Repopulate the popup if it is open.
		 */
		private void recomputeProposals(String filterText) {
			setProposals(getProposals(filterText));
		}

		/*
		 * In an async block, request the proposals. This is used when clients
		 * are in the middle of processing an event that affects the widget
		 * content. By using an async, we ensure that the widget content is up
		 * to date with the event.
		 */
		private void asyncRecomputeProposals(final String filterText) {
			if (isValid()) {
				control.getDisplay().asyncExec(new Runnable() {
					public void run() {
						recordCursorPosition();
						recomputeProposals(filterText);
					}
				});
			} else {
				recomputeProposals(filterText);
			}
		}

		/*
		 * Filter the provided list of content proposals according to the filter
		 * text.
		 */
		private IContentProposal[] filterProposals(
				IContentProposal[] proposals, String filterString) {
			if (filterString.length() == 0) {
				return proposals;
			}

			// Check each string for a match. Use the string displayed to the
			// user, not the proposal content.
			ArrayList list = new ArrayList();
			for (int i = 0; i < proposals.length; i++) {
				String string = getString(proposals[i]);
				if (string.length() >= filterString.length()
						&& string.substring(0, filterString.length())
								.equalsIgnoreCase(filterString)) {
					list.add(proposals[i]);
				}

			}
			return (IContentProposal[]) list.toArray(new IContentProposal[list
					.size()]);
		}

		Listener getTargetControlListener() {
			if (targetControlListener == null) {
				targetControlListener = new TargetControlListener();
			}
			return targetControlListener;
		}
	}

	/**
	 * Flag that controls the printing of debug info.
	 */
	public static final boolean DEBUG = false;

	/**
	 * Indicates that a chosen proposal should be inserted into the field.
	 */
	public static final int PROPOSAL_INSERT = 1;

	/**
	 * Indicates that a chosen proposal should replace the entire contents of
	 * the field.
	 */
	public static final int PROPOSAL_REPLACE = 2;

	/**
	 * Indicates that the contents of the control should not be modified when a
	 * proposal is chosen. This is typically used when a client needs more
	 * specialized behavior when a proposal is chosen. In this case, clients
	 * typically register an IContentProposalListener so that they are notified
	 * when a proposal is chosen.
	 */
	public static final int PROPOSAL_IGNORE = 3;

	/**
	 * Indicates that there should be no filter applied as keys are typed in the
	 * popup.
	 */
	public static final int FILTER_NONE = 1;

	/**
	 * Indicates that a single character filter applies as keys are typed in the
	 * popup.
	 */
	public static final int FILTER_CHARACTER = 2;

	/**
	 * Indicates that a cumulative filter applies as keys are typed in the
	 * popup. That is, each character typed will be added to the filter.
	 */
	public static final int FILTER_CUMULATIVE = 3;

	/*
	 * Set to <code>true</code> to use a Table with SWT.VIRTUAL. This is a
	 * workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=98585#c40
	 * The corresponding SWT bug is
	 * https://bugs.eclipse.org/bugs/show_bug.cgi?id=90321
	 */
	private static final boolean USE_VIRTUAL = !"motif".equals(SWT.getPlatform()); //$NON-NLS-1$

	/*
	 * The delay before showing a secondary popup.
	 */
	private static final int POPUP_DELAY = 750;

	/*
	 * The character height hint for the popup. May be overridden by using
	 * setInitialPopupSize.
	 */
	private static final int POPUP_CHAR_HEIGHT = 10;

	/*
	 * The minimum pixel width for the popup. May be overridden by using
	 * setInitialPopupSize.
	 */
	private static final int POPUP_MINIMUM_WIDTH = 300;

	/*
	 * The pixel offset of the popup from the bottom corner of the control.
	 */
	private static final int POPUP_OFFSET = 3;

	/*
	 * Empty string.
	 */
	private static final String EMPTY = ""; //$NON-NLS-1$

	/*
	 * The object that provides content proposals.
	 */
	private IContentProposalProvider proposalProvider;

	/*
	 * A label provider used to display proposals in the popup, and to extract
	 * Strings from non-String proposals.
	 */
	private ILabelProvider labelProvider;

	/*
	 * The control for which content proposals are provided.
	 */
	private Control control;

	/*
	 * The adapter used to extract the String contents from an arbitrary
	 * control.
	 */
	private IControlContentAdapter controlContentAdapter;

	/*
	 * The popup used to show proposals.
	 */
	private ContentProposalPopup popup;

	/*
	 * The keystroke that signifies content proposals should be shown.
	 */
	private KeyStroke triggerKeyStroke;

	/*
	 * The String containing characters that auto-activate the popup.
	 */
	private String autoActivateString;

	/*
	 * Integer that indicates how an accepted proposal should affect the
	 * control. One of PROPOSAL_IGNORE, PROPOSAL_INSERT, or PROPOSAL_REPLACE.
	 * Default value is PROPOSAL_INSERT.
	 */
	private int proposalAcceptanceStyle = PROPOSAL_INSERT;

	/*
	 * A boolean that indicates whether key events received while the proposal
	 * popup is open should also be propagated to the control. Default value is
	 * true.
	 */
	private boolean propagateKeys = true;

	/*
	 * Integer that indicates the filtering style. One of FILTER_CHARACTER,
	 * FILTER_CUMULATIVE, FILTER_NONE.
	 */
	private int filterStyle = FILTER_NONE;

	/*
	 * The listener we install on the control.
	 */
	private Listener controlListener;

	/*
	 * The list of listeners who wish to be notified when something significant
	 * happens with the proposals.
	 */
	private ListenerList proposalListeners = new ListenerList();

	/*
	 * Flag that indicates whether the adapter is enabled. In some cases,
	 * adapters may be installed but depend upon outside state.
	 */
	private boolean isEnabled = true;

	/*
	 * The delay in milliseconds used when autoactivating the popup.
	 */
	private int autoActivationDelay = 0;
	
	/*
	 * A boolean indicating whether a keystroke has been received.  
	 * Used to see if an autoactivation delay was interrupted by 
	 * a keystroke.
	 */
	private boolean receivedKeyDown;

	/*
	 * The desired size in pixels of the proposal popup.
	 */
	private Point popupSize;

	/*
	 * The remembered position of the insertion position. Not all controls will
	 * restore the insertion position if the proposal popup gets focus, so we
	 * need to remember it.
	 */
	private int insertionPos = -1;

	/**
	 * Construct a content proposal adapter that can assist the user with
	 * choosing content for the field.
	 * 
	 * @param control
	 *            the control for which the adapter is providing content assist.
	 *            May not be <code>null</code>.
	 * @param controlContentAdapter
	 *            the <code>IControlContentAdapter</code> used to obtain and
	 *            update the control's contents as proposals are accepted. May
	 *            not be <code>null</code>.
	 * @param proposalProvider
	 *            the <code>IContentProposalProvider</code> used to obtain
	 *            content proposals for this control, or <code>null</code> if
	 *            no content proposal is available.
	 * @param keyStroke
	 *            the keystroke that will invoke the content proposal popup. If
	 *            this value is <code>null</code>, then proposals will be
	 *            activated automatically when any of the auto activation
	 *            characters are typed.
	 * @param autoActivationCharacters
	 *            An array of characters that trigger auto-activation of content
	 *            proposal. If specified, these characters will trigger
	 *            auto-activation of the proposal popup, regardless of whether
	 *            an explicit invocation keyStroke was specified. If this
	 *            parameter is <code>null</code>, then only a specified
	 *            keyStroke will invoke content proposal. If this parameter is
	 *            <code>null</code> and the keyStroke parameter is
	 *            <code>null</code>, then all alphanumeric characters will
	 *            auto-activate content proposal.
	 */
	public ContentProposalAdapter(Control control,
			IControlContentAdapter controlContentAdapter,
			IContentProposalProvider proposalProvider, KeyStroke keyStroke,
			char[] autoActivationCharacters) {
		super();
		// We always assume the control and content adapter are valid.
		Assert.isNotNull(control);
		Assert.isNotNull(controlContentAdapter);
		this.control = control;
		this.controlContentAdapter = controlContentAdapter;

		// The rest of these may be null
		this.proposalProvider = proposalProvider;
		this.triggerKeyStroke = keyStroke;
		if (autoActivationCharacters != null) {
			this.autoActivateString = new String(autoActivationCharacters);
		}
		addControlListener(control);
	}

	/**
	 * Get the control on which the content proposal adapter is installed.
	 * 
	 * @return the control on which the proposal adapter is installed.
	 */
	public Control getControl() {
		return control;
	}

	/**
	 * Get the label provider that is used to show proposals.
	 * 
	 * @return the {@link ILabelProvider} used to show proposals, or
	 *         <code>null</code> if one has not been installed.
	 */
	public ILabelProvider getLabelProvider() {
		return labelProvider;
	}

	/**
	 * Return a boolean indicating whether the receiver is enabled.
	 * 
	 * @return <code>true</code> if the adapter is enabled, and
	 *         <code>false</code> if it is not.
	 */
	public boolean isEnabled() {
		return isEnabled;
	}

	/**
	 * Set the label provider that is used to show proposals. The lifecycle of
	 * the specified label provider is not managed by this adapter. Clients must
	 * dispose the label provider when it is no longer needed.
	 * 
	 * @param labelProvider
	 *            the (@link ILabelProvider} used to show proposals.
	 */
	public void setLabelProvider(ILabelProvider labelProvider) {
		this.labelProvider = labelProvider;
	}

	/**
	 * Return the proposal provider that provides content proposals given the
	 * current content of the field. A value of <code>null</code> indicates
	 * that there are no content proposals available for the field.
	 * 
	 * @return the {@link IContentProposalProvider} used to show proposals. May
	 *         be <code>null</code>.
	 */
	public IContentProposalProvider getContentProposalProvider() {
		return proposalProvider;
	}

	/**
	 * Set the content proposal provider that is used to show proposals.
	 * 
	 * @param proposalProvider
	 *            the {@link IContentProposalProvider} used to show proposals
	 */
	public void setContentProposalProvider(
			IContentProposalProvider proposalProvider) {
		this.proposalProvider = proposalProvider;
	}

	/**
	 * Return the array of characters on which the popup is autoactivated.
	 * 
	 * @return An array of characters that trigger auto-activation of content
	 *         proposal. If specified, these characters will trigger
	 *         auto-activation of the proposal popup, regardless of whether an
	 *         explicit invocation keyStroke was specified. If this parameter is
	 *         <code>null</code>, then only a specified keyStroke will invoke
	 *         content proposal. If this value is <code>null</code> and the
	 *         keyStroke value is <code>null</code>, then all alphanumeric
	 *         characters will auto-activate content proposal.
	 */
	public char[] getAutoActivationCharacters() {
		if (autoActivateString == null) {
			return null;
		}
		return autoActivateString.toCharArray();
	}

	/**
	 * Set the array of characters that will trigger autoactivation of the
	 * popup.
	 * 
	 * @param autoActivationCharacters
	 *            An array of characters that trigger auto-activation of content
	 *            proposal. If specified, these characters will trigger
	 *            auto-activation of the proposal popup, regardless of whether
	 *            an explicit invocation keyStroke was specified. If this
	 *            parameter is <code>null</code>, then only a specified
	 *            keyStroke will invoke content proposal. If this parameter is
	 *            <code>null</code> and the keyStroke value is
	 *            <code>null</code>, then all alphanumeric characters will
	 *            auto-activate content proposal.
	 * 
	 */
	public void setAutoActivationCharacters(char[] autoActivationCharacters) {
		this.autoActivateString = new String(autoActivationCharacters);
	}

	/**
	 * Set the delay, in milliseconds, used before any autoactivation is
	 * triggered.
	 * 
	 * @return the time in milliseconds that will pass before a popup is
	 *         automatically opened
	 */
	public int getAutoActivationDelay() {
		return autoActivationDelay;

	}

	/**
	 * Set the delay, in milliseconds, used before autoactivation is triggered.
	 * 
	 * @param delay