@Override
    public void clear() {
        setSelected(getSelectedObject(), false);
    }
Constructs a SingleSelectionModel with the given key provider.

@param keyProvider an instance of ProvidesKey<T>, or null if the item should act
                   as its own key
stroom-core-client-widget/src/main/java/stroom/widget/util/client/MySingleSelectionModel.java