@Override
protected void update(final IGroup shape) {
if(shape.isTypeOf(ITextProp.class)) {
final TextPosition tp = shape.getTextPosition();
bButton.setSelected(tp==TextPosition.BOT);
brButton.setSelected(tp==TextPosition.BOT_RIGHT);
blButton.setSelected(tp==TextPosition.BOT_LEFT);
tButton.setSelected(tp==TextPosition.TOP);