Bug 209484 [Databinding] ObservableSetContentProvider does not update knownElements
Build ID: M20071023-1652 Steps To Reproduce: 1. Use a ObservableSetContentProvider in a databinding table 2. Evaluate the knownElements member 3. knownElements is always empty More information: We use a modified ObservableSetContentProvider to bind a table to a model. Moreover, we would like to register for all known Elements in this table using the member 'knownElements' of this class. However, this elements in this member are always empty. There seems to be a bug in method setInput(): 1.) The set of known elements is created in the constructor. 2.) In the inputChanged method (and then in setInput()) the readable set is set to a new value, but the knownElements remains unchanged.
bundles/org.eclipse.core.databinding.observable/src/org/eclipse/core/databinding/observable/set/WritableSet.java
* @param realm
	 * @param c
	 * @param elementType
	 *            can be <code>null</code>
	 */
	public WritableSet(Realm realm, Collection c, Object elementType) {
		super(realm, new HashSet(c), elementType);
		this.elementType = elementType;
	}
	public boolean add(Object o) {
		checkRealm();
		boolean added = wrappedSet.add(o);
		if (added) {
			fireSetChange(Diffs.createSetDiff(Collections.singleton(o), Collections.EMPTY_SET));
		}
		return added;
	}
	public boolean addAll(Collection c) {
		checkRealm();
		Set adds = new HashSet();
		Iterator it = c.iterator();
		while (it.hasNext()) {
			Object element = it.next();
			if (wrappedSet.add(element)) {
				adds.add(element);
			}
		}
		if (adds.size() > 0) {
			fireSetChange(Diffs.createSetDiff(adds, Collections.EMPTY_SET));
			return true;