@Override
public void change(final Component newComponent) {
final Component oldComponent = current;
owner.replaceComponent(oldComponent, newComponent);
previous = oldComponent;
current = newComponent;
}
@Override
public void back() {
final Component oldComponent = current;
final Component newComponent = previous;
owner.replaceComponent(oldComponent, newComponent);
previous = null;
current = newComponent;
}