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
* methods on the elements themselves.
	 * 
	 * @param comparer
	 *            the comparer to use for comparing elements or
	 *            <code>null</code>
	 */
	public void setComparer(IElementComparer comparer) {
		this.comparer = comparer;
		if (elementMap != null) {
			elementMap = new CustomHashtable(elementMap, comparer);
		}
	}
	/**
	 * 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);
	}