class MultiScreenPartWidget extends Composite implements MultiPartWidget {

    @Override
    public boolean selectPart(final PartDefinition part) {
        if (parts.containsKey(part) == false) {
            return false;
        }

        parts.entrySet().forEach(e -> {
            if (e.getKey().equals(part)) {
                e.getValue().show();
            } else {
                e.getValue().hide();
            }
        });
        return true;
    }

}