contentproposaladapter.java

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				rightProposedBounds = getConstrainedShellBounds(rightProposedBounds);
				// If it won't fit on the right, try the left
				if (rightProposedBounds.intersects(parentBounds)) {
					Rectangle leftProposedBounds = new Rectangle(parentBounds.x
							- parentBounds.width - POPUP_HORIZONTALSPACING - 1,
							parentBounds.y, parentBounds.width,
							parentBounds.height);
					leftProposedBounds = getConstrainedShellBounds(leftProposedBounds);
					// If it won't fit on the left, choose the proposed bounds
					// that fits the best
					if (leftProposedBounds.intersects(parentBounds)) {
						if (rightProposedBounds.x - parentBounds.x >= parentBounds.x
								- leftProposedBounds.x) {
							rightProposedBounds.x = parentBounds.x
									+ parentBounds.width
									+ PopupDialog.POPUP_HORIZONTALSPACING;
							proposedBounds = rightProposedBounds;
						} else {
							leftProposedBounds.width = parentBounds.x
									- POPUP_HORIZONTALSPACING
									- leftProposedBounds.x;
							proposedBounds = leftProposedBounds;
						}
					} else {
						// use the proposed bounds on the left
						proposedBounds = leftProposedBounds;
					}
				} else {
					// use the proposed bounds on the right
					proposedBounds = rightProposedBounds;
				}
				getShell().setBounds(proposedBounds);
			}

			/*
			 * Set the text contents of the popup.
			 */
			void setContents(String newContents) {
				if (newContents == null) {
					newContents = EMPTY;
				}
				this.contents = newContents;
				if (text != null && !text.isDisposed()) {
					text.setText(contents);
				}
			}

			/*
			 * Return whether the popup has focus.
			 */
			boolean hasFocus() {
				if (text == null || text.isDisposed()) {
					return false;
				}
				return text.getShell().isFocusControl()
						|| text.isFocusControl();
			}
		}

		/*
		 * The listener installed on the target control.
		 */
		private Listener targetControlListener;

		/*
		 * The listener installed in order to close the popup.
		 */
		private PopupCloserListener popupCloser;

		/*
		 * The table used to show the list of proposals.
		 */
		private Table proposalTable;

		/*
		 * The proposals to be shown (cached to avoid repeated requests).
		 */
		private IContentProposal[] proposals;

		/*
		 * Secondary popup used to show detailed information about the selected
		 * proposal..
		 */
		private InfoPopupDialog infoPopup;

		/*
		 * Flag indicating whether there is a pending secondary popup update.
		 */
		private boolean pendingDescriptionUpdate = false;

		/*
		 * Filter text - tracked while popup is open, only if we are told to
		 * filter
		 */
		private String filterText = EMPTY;

		/**
		 * Constructs a new instance of this popup, specifying the control for
		 * which this popup is showing content, and how the proposals should be
		 * obtained and displayed.
		 * 
		 * @param infoText
		 *            Text to be shown in a lower info area, or
		 *            <code>null</code> if there is no info area.
		 */
		ContentProposalPopup(String infoText) {
			// IMPORTANT: Use of SWT.ON_TOP is critical here for ensuring
			// that the target control retains focus on Mac and Linux. Without
			// it, the focus will disappear, keystrokes will not go to the
			// popup, and the popup closer will wrongly close the popup.
			// On platforms where SWT.ON_TOP overrides SWT.RESIZE, we will live
			// with this.
			// See https://bugs.eclipse.org/bugs/show_bug.cgi?id=126138
			super(control.getShell(), SWT.RESIZE | SWT.ON_TOP, false, false,
					false, false, null, infoText);
			this.proposals = getProposals(filterText);
		}
		/*
		 * Overridden to force change of colors.
		 * See https://bugs.eclipse.org/bugs/show_bug.cgi?id=136244
		 * (non-Javadoc)
		 * @see org.eclipse.jface.dialogs.PopupDialog#createContents(org.eclipse.swt.widgets.Composite)
		 */
		protected Control createContents(Composite parent) {
			Control contents = super.createContents(parent);
			changeDefaultColors(parent);
			return contents;
		}
		
		/*
		 * Set the colors of the popup.  The contents have already been created.
		 */
		private void changeDefaultColors(Control control) {
			applyForegroundColor(getShell().getDisplay().getSystemColor(
					SWT.COLOR_LIST_FOREGROUND), control);
			applyBackgroundColor(getShell().getDisplay().getSystemColor(
					SWT.COLOR_LIST_BACKGROUND), control);
		}

		/*
		 * Creates the content area for the proposal popup. This creates a table
		 * and places it inside the composite. The table will contain a list of
		 * all the proposals.
		 * 
		 * @param parent The parent composite to contain the dialog area; must
		 * not be <code>null</code>.
		 */
		protected final Control createDialogArea(final Composite parent) {
			// Use virtual where appropriate (see flag definition).
			if (USE_VIRTUAL) {
				proposalTable = new Table(parent, SWT.H_SCROLL | SWT.V_SCROLL
						| SWT.VIRTUAL);

				Listener listener = new Listener() {
					public void handleEvent(Event event) {
						handleSetData(event);
					}
				};
				proposalTable.addListener(SWT.SetData, listener);
			} else {
				proposalTable = new Table(parent, SWT.H_SCROLL | SWT.V_SCROLL);
			}

			// compute the proposals to force population of the table.
			recomputeProposals(filterText);

			proposalTable.setHeaderVisible(false);
			proposalTable.addSelectionListener(new SelectionListener() {

				public void widgetSelected(SelectionEvent e) {
					// If a proposal has been selected, show it in the popup.
					// Otherwise close the popup.
					if (e.item == null) {
						if (infoPopup != null) {
							infoPopup.close();
						}
					} else {
						TableItem item = (TableItem) e.item;
						IContentProposal proposal = (IContentProposal) item
								.getData();
						showProposalDescription(proposal.getDescription());
					}
				}

				// Default selection was made. Accept the current proposal.
				public void widgetDefaultSelected(SelectionEvent e) {
					acceptCurrentProposal();
				}
			});
			return proposalTable;
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.jface.dialogs.PopupDialog.adjustBounds()
		 */
		protected void adjustBounds() {
			// Get our control's location in display coordinates.
			Point location = control.getDisplay().map(control.getParent(),
					null, control.getLocation());
			int initialX = location.x + POPUP_OFFSET;
			int initialY = location.y + control.getSize().y + POPUP_OFFSET;
			// If we are inserting content, use the cursor position to
			// position the control.
			if (getProposalAcceptanceStyle() == PROPOSAL_INSERT) {
				Rectangle insertionBounds = controlContentAdapter
						.getInsertionBounds(control);
				initialX = initialX + insertionBounds.x;
				initialY = location.y + insertionBounds.y
						+ insertionBounds.height;
			}

			// If there is no specified size, force it by setting
			// up a layout on the table.
			if (popupSize == null) {
				GridData data = new GridData(GridData.FILL_BOTH);
				data.heightHint = proposalTable.getItemHeight()
						* POPUP_CHAR_HEIGHT;
				data.widthHint = Math.max(control.getSize().x,
						POPUP_MINIMUM_WIDTH);
				proposalTable.setLayoutData(data);
				getShell().pack();
				popupSize = getShell().getSize();
			}
			getShell().setBounds(initialX, initialY, popupSize.x, popupSize.y);

			// Now set up a listener to monitor any changes in size.
			getShell().addListener(SWT.Resize, new Listener() {
				public void handleEvent(Event e) {
					popupSize = getShell().getSize();
					if (infoPopup != null) {
						infoPopup.adjustBounds();
					}
				}
			});
		}

		/*
		 * Handle the set data event. Set the item data of the requested item to
		 * the corresponding proposal in the proposal cache.
		 */
		private void handleSetData(Event event) {
			TableItem item = (TableItem) event.item;
			int index = proposalTable.indexOf(item);

			if (0 <= index && index < proposals.length) {
				IContentProposal current = proposals[index];
				item.setText(getString(current));
				item.setImage(getImage(current));
				item.setData(current);
			} else {
				// this should not happen, but does on win32
			}
		}

		/*
		 * Caches the specified proposals and repopulates the table if it has
		 * been created.
		 */
		private void setProposals(IContentProposal[] newProposals) {
			if (newProposals == null || newProposals.length == 0) {
				newProposals = getEmptyProposalArray();
			}
			this.proposals = newProposals;

			// If there is a table
			if (isValid()) {
				final int newSize = newProposals.length;
				if (USE_VIRTUAL) {
					// Set and clear the virtual table. Data will be
					// provided in the SWT.SetData event handler.
					proposalTable.setItemCount(newSize);
					proposalTable.clearAll();
				} else {
					// Populate the table manually
					proposalTable.setRedraw(false);
					proposalTable.setItemCount(newSize);
					TableItem[] items = proposalTable.getItems();
					for (int i = 0; i < items.length; i++) {
						TableItem item = items[i];
						IContentProposal proposal = newProposals[i];
						item.setText(getString(proposal));
						item.setImage(getImage(proposal));
						item.setData(proposal);
					}
					proposalTable.setRedraw(true);
				}
				// Default to the first selection if there is content.
				if (newProposals.length > 0) {
					selectProposal(0);
				} else {
					// No selection, close the secondary popup if it was open
					if (infoPopup != null) {
						infoPopup.close();
					}

				}
			}
		}

		/*
		 * Get the string for the specified proposal. Always return a String of
		 * some kind.
		 */
		private String getString(IContentProposal proposal) {
			if (proposal == null) {
				return EMPTY;
			}
			if (labelProvider == null) {
				return proposal.getLabel() == null ? proposal.getContent()
						: proposal.getLabel();
			}
			return labelProvider.getText(proposal);
		}

		/*
		 * Get the image for the specified proposal. If there is no image
		 * available, return null.
		 */
		private Image getImage(IContentProposal proposal) {
			if (proposal == null || labelProvider == null) {
				return null;
			}
			return labelProvider.getImage(proposal);
		}

		/*
		 * Return an empty array. Used so that something always shows in the
		 * proposal popup, even if no proposal provider was specified.
		 */
		private IContentProposal[] getEmptyProposalArray() {
			return new IContentProposal[0];
		}

		/*
		 * Answer true if the popup is valid, which means the table has been
		 * created and not disposed.
		 */
		private boolean isValid() {
			return proposalTable != null && !proposalTable.isDisposed();
		}

		/*
		 * Return whether the receiver has focus.
		 */
		private boolean hasFocus() {
			if (!isValid()) {
				return false;
			}
			return getShell().isFocusControl()
					|| proposalTable.isFocusControl();
		}

		/*
		 * Return the current selected proposal.
		 */
		private IContentProposal getSelectedProposal() {
			if (isValid()) {
				int i = proposalTable.getSelectionIndex();
				if (proposals == null || i < 0 || i >= proposals.length) {
					return null;
				}
				return proposals[i];
			}
			return null;
		}

		/*
		 * Select the proposal at the given index.
		 */
		private void selectProposal(int index) {
			Assert
					.isTrue(index >= 0,
							"Proposal index should never be negative"); //$NON-NLS-1$
			if (!isValid() || proposals == null || index >= proposals.length) {
				return;
			}
			proposalTable.setSelection(index);
			proposalTable.showSelection();

			showProposalDescription(proposals[index].getDescription());
		}

		/**
		 * Opens this ContentProposalPopup. This method is extended in order to
		 * add the control listener when the popup is opened and to invoke the
		 * secondary popup if applicable.
		 * 
		 * @return the return code
		 * 
		 * @see org.eclipse.jface.window.Window#open()
		 */
		public int open() {
			int value = super.open();
			if (popupCloser == null) {
				popupCloser = new PopupCloserListener();
			}
			popupCloser.installListeners();
			IContentProposal p = getSelectedProposal();
			if (p != null) {
				showProposalDescription(p.getDescription());
			}
			return value;
		}

		/**
		 * Closes this popup. This method is extended to remove the control
		 * listener.
		 * 
		 * @return <code>true</code> if the window is (or was already) closed,
		 *         and <code>false</code> if it is still open
		 */
		public boolean close() {
			popupCloser.removeListeners();
			if (infoPopup != null) {
				infoPopup.close();
			}
			return super.close();
		}

		/*
		 * Get the proposals from the proposal provider. The provider may or may
		 * not filter the proposals based on the specified filter text.
		 */
		private IContentProposal[] getProposals(String filterString) {
			if (proposalProvider == null || !isValid()) {
				return null;
			}
			int position = insertionPos;
			if (position == -1) {
				position = getControlContentAdapter().getCursorPosition(
						getControl());
			}
			String contents = getControlContentAdapter().getControlContents(
					getControl());
			IContentProposal[] proposals = proposalProvider.getProposals(
					contents, position);
			if (filterStyle != FILTER_NONE) {
				return filterProposals(proposals, filterString);
			}
			return proposals;
		}

		/*
		 * Show the proposal description in a secondary popup.
		 */
		private void showProposalDescription(String description) {
			// If we do not already have a pending update, then
			// create a thread now that will show the proposal description
			if (!pendingDescriptionUpdate && description != null) {
				// Create a thread that will sleep for the specified delay
				// before creating the popup. We do not use Jobs since this
				// code must be able to run independently of the Eclipse
				// runtime.
				Runnable runnable = new Runnable() {
					public void run() {
						pendingDescriptionUpdate = true;
						try {