structuredviewer.java

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	}

	/**
	 * Hook for testing.
	 * @param element
	 * @return Widget
	 */
	public Widget testFindItem(Object element) {
		return findItem(element);
	}

	/**
	 * Hook for testing.
	 * @param element
	 * @return Widget[]
	 * @since 3.2
	 */
	public Widget[] testFindItems(Object element) {
		return findItems(element);
	}
	
	/**
	 * Removes all elements from the map.
	 * <p>
	 * This method is internal to the framework; subclassers should not call
	 * this method.
	 * </p>
	 */
	protected void unmapAllElements() {
		if (elementMap != null) {
			elementMap = newHashtable(CustomHashtable.DEFAULT_CAPACITY);
		}
	}

	/**
	 * Removes the given element from the internal element to widget map. Does
	 * nothing if mapping is disabled. If mapping is enabled, the given element
	 * must be present.
	 * <p>
	 * This method is internal to the framework; subclassers should not call
	 * this method.
	 * </p>
	 * 
	 * @param element
	 *            the element
	 */
	protected void unmapElement(Object element) {
		if (elementMap != null) {
			elementMap.remove(element);
		}
	}

	/**
	 * Removes the given association from the internal element to widget map.
	 * Does nothing if mapping is disabled, or if the given element does not map
	 * to the given item.
	 * <p>
	 * This method is internal to the framework; subclassers should not call
	 * this method.
	 * </p>
	 * 
	 * @param element
	 *            the element
	 * @param item the item to unmap
	 * @since 2.0
	 */
	protected void unmapElement(Object element, Widget item) {
		// double-check that the element actually maps to the given item before
		// unmapping it
		if (elementMap != null) {
			Object widgetOrWidgets = elementMap.get(element);
			if (widgetOrWidgets == null) {
				// item was not mapped, return
				return;
			} else if (widgetOrWidgets instanceof Widget) {
				if (item == widgetOrWidgets) {
					elementMap.remove(element);
				}
			} else {
				Widget[] widgets = (Widget[]) widgetOrWidgets;
				int indexOfItem = Arrays.asList(widgets).indexOf(item);
				if (indexOfItem == -1) {
					return;
				}
				int length = widgets.length;
				if (indexOfItem == 0) {
					if(length == 1) {
						elementMap.remove(element);
					} else {
						Widget[] updatedWidgets = new Widget[length - 1];
						System.arraycopy(widgets, 1, updatedWidgets, 0, length -1 );
						elementMap.put(element, updatedWidgets);
					}
				} else {
					Widget[] updatedWidgets = new Widget[length - 1];
					System.arraycopy(widgets, 0, updatedWidgets, 0, indexOfItem);
					System.arraycopy(widgets, indexOfItem + 1, updatedWidgets, indexOfItem, length - indexOfItem - 1);
					elementMap.put(element, updatedWidgets);
				}
			}
		}
	}

	/**
	 * Updates the given elements' presentation when one or more of their
	 * properties change. Only the given elements are updated.
	 * <p>
	 * This does not handle structural changes (e.g. addition or removal of
	 * elements), and does not update any other related elements (e.g. child
	 * elements). To handle structural changes, use the <code>refresh</code>
	 * methods instead.
	 * </p>
	 * <p>
	 * This should be called when an element has changed in the model, in order
	 * to have the viewer accurately reflect the model. This method only affects
	 * the viewer, not the model.
	 * </p>
	 * <p>
	 * Specifying which properties are affected may allow the viewer to optimize
	 * the update. For example, if the label provider is not affected by changes
	 * to any of these properties, an update may not actually be required.
	 * Specifing <code>properties</code> as <code>null</code> forces a full
	 * update of the given elements.
	 * </p>
	 * <p>
	 * If the viewer has a sorter which is affected by a change to one of the
	 * properties, the elements' positions are updated to maintain the sort
	 * order.
	 * </p>
	 * <p>
	 * If the viewer has a filter which is affected by a change to one of the
	 * properties, elements may appear or disappear if the change affects
	 * whether or not they are filtered out.
	 * </p>
	 * 
	 * @param elements
	 *            the elements
	 * @param properties
	 *            the properties that have changed, or <code>null</code> to
	 *            indicate unknown
	 */
	public void update(Object[] elements, String[] properties) {
		for (int i = 0; i < elements.length; ++i) {
			update(elements[i], properties);
		}
	}

	/**
	 * Updates the given element's presentation when one or more of its
	 * properties changes. Only the given element is updated.
	 * <p>
	 * This does not handle structural changes (e.g. addition or removal of
	 * elements), and does not update any other related elements (e.g. child
	 * elements). To handle structural changes, use the <code>refresh</code>
	 * methods instead.
	 * </p>
	 * <p>
	 * This should be called when an element has changed in the model, in order
	 * to have the viewer accurately reflect the model. This method only affects
	 * the viewer, not the model.
	 * </p>
	 * <p>
	 * Specifying which properties are affected may allow the viewer to optimize
	 * the update. For example, if the label provider is not affected by changes
	 * to any of these properties, an update may not actually be required.
	 * Specifing <code>properties</code> as <code>null</code> forces a full
	 * update of the element.
	 * </p>
	 * <p>
	 * If the viewer has a sorter which is affected by a change to one of the
	 * properties, the element's position is updated to maintain the sort order.
	 * </p>
	 * <p>
	 * If the viewer has a filter which is affected by a change to one of the
	 * properties, the element may appear or disappear if the change affects
	 * whether or not the element is filtered out.
	 * </p>
	 * 
	 * @param element
	 *            the element
	 * @param properties
	 *            the properties that have changed, or <code>null</code> to
	 *            indicate unknown
	 */
	public void update(Object element, String[] properties) {
		Assert.isNotNull(element);
		Widget[] items = findItems(element);

		for (int i = 0; i < items.length; i++) {
			internalUpdate(items[i], element, properties);
		}		
	}

	/**
     * Updates the given element's presentation when one or more of its
     * properties changes. Only the given element is updated.
     * <p>
     * EXPERIMENTAL.  Not to be used except by JDT.
     * This method was added to support JDT's explorations
     * into grouping by working sets, which requires viewers to support multiple 
     * equal elements.  See bug 76482 for more details.  This support will
     * likely be removed in Eclipse 3.3 in favour of proper support for
     * multiple equal elements (which was implemented for AbtractTreeViewer in 3.2). 
     * </p>
     * @param widget
     *            the widget for the element
     * @param element
     *            the element
     * @param properties
     *            the properties that have changed, or <code>null</code> to
     *            indicate unknown
     */
	protected void internalUpdate(Widget widget, Object element, String[] properties) {
		boolean needsRefilter = false;
		if (properties != null) {
			for (int i = 0; i < properties.length; ++i) {
				needsRefilter = needsRefilter(element, properties[i]);
				if (needsRefilter) {
					break;
				}
			}
		}
		if (needsRefilter) {
			refresh();
			return;
		}

		boolean needsUpdate;
		if (properties == null) {
			needsUpdate = true;
		} else {
			needsUpdate = false;
			IBaseLabelProvider labelProvider = getLabelProvider();
			for (int i = 0; i < properties.length; ++i) {
				needsUpdate = labelProvider.isLabelProperty(element, properties[i]);
				if (needsUpdate) {
					break;
				}
			}
		}
		if (needsUpdate) {
			updateItem(widget, element);
		}
	}

	/**
	 * Copies attributes of the given element into the given widget.
	 * <p>
	 * This method is internal to the framework; subclassers should not call
	 * this method. Calls <code>doUpdateItem(widget, element, true)</code>.
	 * </p>
	 * 
	 * @param widget
	 *            the widget
	 * @param element
	 *            the element
	 */
	protected final void updateItem(Widget widget, Object element) {
		SafeRunnable.run(new UpdateItemSafeRunnable(widget, element, true));
	}

	/**
	 * Updates the selection of this viewer.
	 * <p>
	 * This framework method should be called when the selection in the viewer
	 * widget changes.
	 * </p>
	 * <p>
	 * The default implementation of this method notifies all selection change
	 * listeners recorded in an internal state variable. Overriding this method
	 * is generally not required; however, if overriding in a subclass,
	 * <code>super.updateSelection</code> must be invoked.
	 * </p>
	 * 
	 * @param selection
	 *            the selection, or <code>null</code> if none
	 */
	protected void updateSelection(ISelection selection) {
		SelectionChangedEvent event = new SelectionChangedEvent(this, selection);
		fireSelectionChanged(event);
	}

	/**
	 * Returns whether this structured viewer is configured to use an internal
	 * map to speed up the mapping between elements and SWT items.
	 * <p>
	 * The default implementation of this framework method checks whether the
	 * internal map has been initialized.
	 * </p>
	 * 
	 * @return <code>true</code> if the element map is enabled, and
	 *         <code>false</code> if disabled
	 */
	protected boolean usingElementMap() {
		return elementMap != null;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.jface.viewers.ContentViewer#setLabelProvider(org.eclipse.jface.viewers.IBaseLabelProvider)
	 */
	public void setLabelProvider(IBaseLabelProvider labelProvider) {
		if (labelProvider instanceof IColorProvider || labelProvider instanceof IFontProvider) {
			colorAndFontCollector = new ColorAndFontCollectorWithProviders(labelProvider);
		} else {
			colorAndFontCollector = new ColorAndFontCollector();
		}
		super.setLabelProvider(labelProvider);
		
	}
	
	/**
	 * Build a label up for the element using the supplied label provider.
	 * @param updateLabel The ViewerLabel to collect the result in
	 * @param element The element being decorated.
	 */
	protected void buildLabel(ViewerLabel updateLabel, Object element){

		if (getLabelProvider() instanceof IViewerLabelProvider) {
			IViewerLabelProvider itemProvider = (IViewerLabelProvider) getLabelProvider();
			itemProvider.updateLabel(updateLabel, element);
            		
			colorAndFontCollector.setUsedDecorators();
			
			if(updateLabel.hasNewBackground()) {
				colorAndFontCollector.setBackground(updateLabel.getBackground());
			}
			
			if(updateLabel.hasNewForeground()) {
				colorAndFontCollector.setForeground(updateLabel.getForeground());
			}
			
			if(updateLabel.hasNewFont()) {
				colorAndFontCollector.setFont(updateLabel.getFont());
			}
			return;

		} 
		
		if(getLabelProvider() instanceof ILabelProvider){
			ILabelProvider labelProvider = (ILabelProvider) getLabelProvider();
			updateLabel.setText(labelProvider.getText(element));
			updateLabel.setImage(labelProvider.getImage(element));
		}
	
	}
	
	/**
	 * Build a label up for the element using the supplied label provider.
	 * @param updateLabel The ViewerLabel to collect the result in
	 * @param element The element being decorated.
	 * @param labelProvider ILabelProvider the labelProvider for the receiver.
	 */
	void buildLabel(ViewerLabel updateLabel, Object element,IViewerLabelProvider labelProvider){

			labelProvider.updateLabel(updateLabel, element);
            		
			colorAndFontCollector.setUsedDecorators();
			
			if(updateLabel.hasNewBackground()) {
				colorAndFontCollector.setBackground(updateLabel.getBackground());
			}
			
			if(updateLabel.hasNewForeground()) {
				colorAndFontCollector.setForeground(updateLabel.getForeground());
			}
			
			if(updateLabel.hasNewFont()) {
				colorAndFontCollector.setFont(updateLabel.getFont());
			}
	
	}
	
	/**
	 * Build a label up for the element using the supplied label provider.
	 * @param updateLabel The ViewerLabel to collect the result in
	 * @param elementPath The path of the element being decorated.
	 * @param labelProvider ILabelProvider the labelProvider for the receiver.
	 */
	void buildLabel(ViewerLabel updateLabel, TreePath elementPath,ITreePathLabelProvider labelProvider){

			labelProvider.updateLabel(updateLabel, elementPath);
            		
			colorAndFontCollector.setUsedDecorators();
			
			if(updateLabel.hasNewBackground()) {
				colorAndFontCollector.setBackground(updateLabel.getBackground());
			}
			
			if(updateLabel.hasNewForeground()) {
				colorAndFontCollector.setForeground(updateLabel.getForeground());
			}
			
			if(updateLabel.hasNewFont()) {
				colorAndFontCollector.setFont(updateLabel.getFont());
			}
	
	}
	
	/**
	 * Build a label up for the element using the supplied label provider.
	 * @param updateLabel The ViewerLabel to collect the result in
	 * @param element The element being decorated.
	 * @param labelProvider ILabelProvider the labelProvider for the receiver.
	 */
	void buildLabel(ViewerLabel updateLabel, Object element,ILabelProvider labelProvider){
			updateLabel.setText(labelProvider.getText(element));
			updateLabel.setImage(labelProvider.getImage(element));
	}

	/**
	 * Get the ColorAndFontCollector for the receiver.
	 * @return ColorAndFontCollector 
	 * @since 3.1
	 */
	protected ColorAndFontCollector getColorAndFontCollector() {
		return colorAndFontCollector;
	}

}