// When the active part changes and does not select a FeatureType
// we still need to trigger aboutToBeHidden() and aboutToBeShown().
if (!thisActivated && !part.equals(contributor)) {
// check if this view is a proxy for another contributor
IContributedContentsView view = (IContributedContentsView) part
.getAdapter(IContributedContentsView.class);
if (view != null && view.getContributingPart() != null
&& view.getContributingPart().equals(contributor)) {
// this view is a proxy for our current contributor
} else {
// we are actually switching contributors
if (activePropertySheet) {
if (currentTab != null) {