Bug 24521 [Viewers] TreeViewer.update() does not work correctly with filter
When I add an element which does not satisfy the filtering condition and then update it so that it does, call to update does not show the element. This is because[StructuredViewer.update]: public void update(Object element, String[] properties) { Assert.isNotNull(element); | Widget item = findItem(element); | if (item == null) | return; the code silently ignores that the element may become visible... btw. later in code of this method: if (needsRefilter) { refresh(); return; } This is quite inefficient, as it needs to query all visible items; however only one element may actually change (change visibility and/or sort order).
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/StructuredViewer.java
/**
	 * 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);
		}
	}
	/**